Search results for: open and green spaces
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6071

Search results for: open and green spaces

1481 Enhancing Postharvest Quality and Shelf-Life of Leaf Lettuce (Lactuca sativa L.) by Altering Growing Conditions

Authors: Jung-Soo Lee, Ujjal Kumar Nath, IllSup Nou, Dulal Chandra

Abstract:

Leaf lettuce is one of the most important leafy vegetables that is used as raw for salad and part of everyday dishes in many parts of the world including Asian countries. Since it is used as fresh, its quality maintenance is crucial which depends on several pre- and postharvest factors. In order to investigate the effects of pre-fix factors on the postharvest quality, the interaction of pre-fix factors such as growing conditions and fixed factor like cultivars were evaluated. Four Korean leaf lettuce cultivars ‘Cheongchima’, ‘Cheongchuckmyeon’, ‘Geockchima’ and ‘Geockchuckmyeon’ were grown under natural condition (as control) and altered growing condition (green house) with excess soil water and 50% shading to monitor their postharvest qualities. Several growth parameters like plant height, number of leaves, leaf thickness, fresh biomass yield as well as postharvest qualities like fresh weight loss, respiration rate, changes in color and shelf-life were measured in lettuce during storage up to 36 days at 5°C. Plant height and the number of leaves were affected by both pre-fix growing conditions as well as the cultivars. However, fresh biomass yield was affected by only growing condition, whereas leaf thickness was affected by cultivars. Additionally, the degrees of fresh weight loss and respiration rate of leaf lettuce at postharvest stages were influenced by pre-fix growing conditions and cultivars. However, changes in color of leaves during storage were less remarkable in samples harvested from of ‘Cheongchima’ and ‘Cheongchuckmyeon’ cultivars grown in excess watering with 50% shade than that grown in control condition. Consequently, these two cultivars also showed longer shelf-life when they were grown in excess watering with 50% shade than other cultivars or samples were grown in control condition. Based on the measured parameters, it can be concluded that postharvest quality of leaf lettuce might be accelerated by growing lettuce under excess soil water with 50% shading.

Keywords: cultivar, growing condition, leaf lettuce, postharvest quality, shelf-life

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1480 Effect of Injection Pressure and Fuel Injection Timing on Emission and Performance Characteristics of Karanja Biodiesel and its Blends in CI Engine

Authors: Mohan H., C. Elajchet Senni

Abstract:

In the present of high energy consumption in every sphere of life, renewable energy sources are emerging as alternative to conventional fuels for energy security, mitigating green house gas emission and climate change. There has been a world wide interest in searching for alternatives to petroleum derived fuels due to their depletion as well as due to the concern for the environment. Vegetable oils have capability to solve this problem because they are renewable and lead to reduction in environmental pollution. But high smoke emission and lower thermal efficiency are the main problems associated with the use of neat vegetable oils in diesel engines. In the present work, performance, combustion and emission characteristics of CI engine fuelled with 20% by vol. methyl esters mixed with Karanja seed Oil, and Fuel injection pressures of 200 bar and 240 bar, injection timings (21°,23° and 25° BTDC) and Proportion B20 diesel respectively. Vegetable oils have capability to solve this problem because they are renewable and lead to reduction in environmental pollution. But, high smoke emission and lower thermal efficiency are the main problems associated with the use of neat vegetable oils in diesel engines. In the present work, performance, combustion and emission characteristics of CI engine fuelled with 20% by vol. methyl esters mixed with Karanja seed Oil, and Fuel injection pressures of 200 bar and 240 bar ,Injection timings (21°,23° and 25° BTDC) and Proportion B20 diesel respectively. Various performance, combustion and emission characteristics such as thermal efficiency, and brake specific fuel consumption, maximum cylinder pressure, instantaneous heat release, cumulative heat release with respect to crank angle, ignition lag, combustion duration, HC, NOx, CO, exhaust temperature and smoke intensity were measured.

Keywords: karanja oil, injection pressure, injection timing, karanja oil methyl ester

Procedia PDF Downloads 294
1479 Motivation for Work and Organizational Commitment in an Engineering Public Faculty: A Perception of Technical and Administrative Employees

Authors: Fátima Aparecida de Carvalho, Ester Eliane Jeunon

Abstract:

This study addresses issues in the public service: motivation to work and organizational commitment. The goal of this research was to examine how it configures the motivation to work and organizational commitment of the technical and administrative effective staff of the School of Engineering at UFMG. For this purpose a descriptive research under a quantitative and qualitative approach has been performed. In the quantitative research it has been applied a questionnaire to all 146 technical and administrative institution effective staff, that configures a census research. This questionnaire was divided into three parts, the first one aimed at performing a socio-demographic survey of participants, the second one aimed to measure motivation and the third one aimed at measuring organizational commitment. The Bases Organizational Commitment Scale (EBACO) was used in the analysis of data obtained in the third part of the questionnaire. The qualitative research was conducted through interviews with 08 managers, with open-ended questions structured in an analysis category, thus contemplating the administrative structure of the School of Engineering. The results of the research revealed that there is no relevant difference between the hygiene and motivational indices, related to the staff´s gender and area of work. Nonetheless, it was observed higher motivational indices for staff with shorter duration of employment in the institution. Also, the results shown high organizational commitment of the staff with the institution, with a predominance of the component “Requirement for performance”, followed by commitments “Consistent line of activity”, “Affiliative” and “Affective”, which reached almost tge some average in this study. Finally the results showed that all commitment indices have positive moderated correlation to the motivational indices, except the “shortage of alternative” index.

Keywords: motivation to work, organizational commitment, public service, human resources

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1478 Associated Factors of Hypertension, Hypercholesterolemia and Double Burden Hypertension-Hypercholesterolemia in Patients With Congestive Heart Failure: Hospital Based Study

Authors: Pierre Mintom, William Djeukeu Asongni, Michelle Moni, William Dakam, Christine Fernande Nyangono Biyegue.

Abstract:

Background: In order to prevent congestive heart failure, control of hypertension and hypercholesterolemia is necessary because those risk factors frequently occur in combination. Objective: The aim of the study is to determine the prevalence and risk factors of hypertension, hypercholesterolemia and double burden HTA-Hypercholesterolemia in patients with congestive heart failure. Methodology: A database of 98 patients suffering from congestive heart failure was used. The latter were recruited from August 15, 2017, to March 5, 2018, in the Cardiology department of Deido District Hospital of Douala. This database provides information on sociodemographic parameters, biochemical examinations, characteristics of heart failure and food consumption. ESC/ESH and NCEP-ATPIII definitions were used to define Hypercholesterolemia (total cholesterol ≥200mg/dl), Hypertension (SBP≥140mmHg and/or DBP≥90mmHg). Double burden hypertension-hypercholesterolemia was defined as follows: total cholesterol (CT)≥200mg/dl, SBP≥140mmHg and DBP≥90mmHg. Results: The prevalence of hypertension (HTA), hypercholesterolemia (hyperchol) and double burden HTA-Hyperchol were 61.2%, 66.3% and 45.9%, respectively. No sociodemographic factor was associated with hypertension, hypercholesterolemia and double burden, but Male gender was significantly associated (p<0.05) with hypercholesterolemia. HypoHDLemia significantly increased hypercholesterolemia and the double burden by 19.664 times (p=0.001) and 14.968 times (p=0.021), respectively. Regarding dietary habits, the consumption of rice, peanuts and derivatives and cottonseed oil respectively significantly (p<0.05) exposed to the occurrence of hypertension. The consumption of tomatoes, green bananas, corn and derivatives, peanuts and derivatives and cottonseed oil significantly exposed (p<0.05) to the occurrence of hypercholesterolemia. The consumption of palm oil and cottonseed oil exposed the occurrence of the double burden of hypertension-hypercholesterolemia. Consumption of eggs protects against hypercholesterolemia, and consumption of peanuts and tomatoes protects against the double burden. Conclusion: hypercholesterolemia associated with hypertension appears as a complicating factor of congestive heart failure. Key risk factors are mainly diet-based, suggesting the importance of nutritional education for patients. New management protocols emphasizing diet should be considered.

Keywords: risk factors, hypertension, hypercholesterolemia, congestive heart failure

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1477 A Migration Policy Gone Wrong: A Study on How the Encampment Policy Undermines Refugees’ Potentials and Fails Local Economy: A Case of East Africa

Authors: John Bosco Ngendakurio

Abstract:

The key question this paper asks is, ‘how does the refugee encampment policy undermine refugees’ potentials and fail local economy in East African countries?’ It is important to develop a full understanding of the legacies of the encampment policy for refugees’ performances economically, socially, and politically. The negative impacts of the encampment policy include the lack of participation or access to opportunities outside the refugee camps such as employment, education, and local integration, unfair imprisonments and constant alienation of refugees, mental and physical health issues, just to name a few. Evidence suggests that refugee camps in East Africa have progressively become open detention centres due to their designs, their locations, and movement restrictions imposed on refugees. Such restrictions in a region that hosts millions of refugees do not only undermine refugees’ potentials, but it also hurts the local economy- host countries miss out in many ways. Outlining the negative impacts of the encampment policy will enable governments and relevant non-governmental actors, including policymakers, to re-consider this policy with the aim to improve refugees’ participation and contributions in the broader society, promote socially cohesive practices, and help millions of refugees gain independence and reach their potentials financially, socially and politically, finally and truly giving the voice to the voiceless. The encampment policy undermines the general human security in East Africa, and it is one of the migration practices showcasing East African governments’ lack of will to protect human rights, especially within the most vulnerable population groups such as refugees.

Keywords: migration policy, immigration, refugees, encampment, migration, integration, social cohesion

Procedia PDF Downloads 139
1476 Discrimination of Bio-Analytes by Using Two-Dimensional Nano Sensor Array

Authors: P. Behera, K. K. Singh, D. K. Saini, M. De

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Implementation of 2D materials in the detection of bio analytes is highly advantageous in the field of sensing because of its high surface to volume ratio. We have designed our sensor array with different cationic two-dimensional MoS₂, where surface modification was achieved by cationic thiol ligands with different functionality. Green fluorescent protein (GFP) was chosen as signal transducers for its biocompatibility and anionic nature, which can bind to the cationic MoS₂ surface easily, followed by fluorescence quenching. The addition of bio-analyte to the sensor can decomplex the cationic MoS₂ and GFP conjugates, followed by the regeneration of GFP fluorescence. The fluorescence response pattern belongs to various analytes collected and transformed to linear discriminant analysis (LDA) for classification. At first, 15 different proteins having wide range of molecular weight and isoelectric points were successfully discriminated at 50 nM with detection limit of 1 nM. The sensor system was also executed in biofluids such as serum, where 10 different proteins at 2.5 μM were well separated. After successful discrimination of protein analytes, the sensor array was implemented for bacteria sensing. Six different bacteria were successfully classified at OD = 0.05 with a detection limit corresponding to OD = 0.005. The optimized sensor array was able to classify uropathogens from non-uropathogens in urine medium. Further, the technique was applied for discrimination of bacteria possessing resistance to different types and amounts of drugs. We found out the mechanism of sensing through optical and electrodynamic studies, which indicates the interaction between bacteria with the sensor system was mainly due to electrostatic force of interactions, but the separation of native bacteria from their drug resistant variant was due to Van der Waals forces. There are two ways bacteria can be detected, i.e., through bacterial cells and lysates. The bacterial lysates contain intracellular information and also safe to analysis as it does not contain live cells. Lysates of different drug resistant bacteria were patterned effectively from the native strain. From unknown sample analysis, we found that discrimination of bacterial cells is more sensitive than that of lysates. But the analyst can prefer bacterial lysates over live cells for safer analysis.

Keywords: array-based sensing, drug resistant bacteria, linear discriminant analysis, two-dimensional MoS₂

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1475 Topping Failure Analysis of Anti-Dip Bedding Rock Slopes Subjected to Crest Loads

Authors: Chaoyi Sun, Congxin Chen, Yun Zheng, Kaizong Xia, Wei Zhang

Abstract:

Crest loads are often encountered in hydropower, highway, open-pit and other engineering rock slopes. Toppling failure is one of the most common deformation failure types of anti-dip bedding rock slopes. Analysis on such failure of anti-dip bedding rock slopes subjected to crest loads has an important influence on engineering practice. Based on the step-by-step analysis approach proposed by Goodman and Bray, a geo-mechanical model was developed, and the related analysis approach was proposed for the toppling failure of anti-dip bedding rock slopes subjected to crest loads. Using the transfer coefficient method, a formulation was derived for calculating the residual thrust of slope toe and the support force required to meet the requirements of the slope stability under crest loads, which provided a scientific reference to design and support for such slopes. Through slope examples, the influence of crest loads on the residual thrust and sliding ratio coefficient was investigated for cases of different block widths and slope cut angles. The results show that there exists a critical block width for such slope. The influence of crest loads on the residual thrust is non-negligible when the block thickness is smaller than the critical value. Moreover, the influence of crest loads on the slope stability increases with the slope cut angle and the sliding ratio coefficient of anti-dip bedding rock slopes increases with the crest loads. Finally, the theoretical solutions and numerical simulations using Universal Distinct Element Code (UDEC) were compared, in which the consistent results show the applicability of both approaches.

Keywords: anti-dip bedding rock slope, crest loads, stability analysis, toppling failure

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1474 On the Monitoring of Structures and Soils by Tromograph

Authors: Magarò Floriana, Zinno Raffaele

Abstract:

Since 2009, with the coming into force of the January 14, 2008 Ministerial Decree "New technical standards for construction", and the explanatory ministerial circular N°.617 of February 2, 2009, the question of seismic hazard and the design of seismic-resistant structures in Italy has acquired increasing importance. One of the most discussed aspects in recent Italian and international scientific literature concerns the dynamic interaction between land and structure, and the effects which dynamic coupling may have on individual buildings. In effect, from systems dynamics, it is well known that resonance can have catastrophic effects on a stimulated system, leading to a response that is not compatible with the previsions in the design phase. The method used in this study to estimate the frequency of oscillation of the structure is as follows: the analysis of HVSR (Horizontal to Vertical Spectral Ratio) relations. This allows for evaluation of very simple oscillation frequencies for land and structures. The tool used for data acquisition is an experimental digital tromograph. This is an engineered development of the experimental Languamply RE 4500 tromograph, equipped with an engineered amplification circuit and improved electronically using extremely small electronic components (size of each individual amplifier 16 x 26 mm). This tromograph is a modular system, completely "free" and "open", designed to interface Windows, Linux, OSX and Android with the outside world. It an amplifier designed to carry out microtremor measurements, yet which will also be useful for seismological and seismic measurements in general. The development of single amplifiers of small dimension allows for a very clean signal since being able to position it a few centimetres from the geophone eliminates cable “antenna” phenomena, which is a necessary characteristic in seeking to have signals which are clean at the very low voltages to be measured.

Keywords: microtremor, HVSR, tromograph, structural engineering

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1473 Knowledge And Attitude of Female Workers in Selected Rural Local Government Areas of Imo State, Nigeria Towards Cervical Cancer and Its Screening

Authors: Peter O. Nwadike, Sylvia O. Anyadoh-Nwadike, Chukwunonyerem Ogwunga, I. N. S. Dozie

Abstract:

Purpose: This study was aimed at determining the knowledge and attitude of female workers in six selected rural Local Government Areas of Imo State (Ezinihitte Mbaise, Ngor Okpala, Ohaji/Egbema, Ideato South, Ihitte Uboma and Obowo) towards cervical cancer and its screening. Methodology: Data was collected using a validated open-ended, semi-structured questionnaire. After responses to the questionnaire were received, a seminar on Cervical cancer and its screening was delivered to the respondents. Afterward, a second set of the same questionnaires was administered to the same respondents. A total of 460 women of reproductive age were randomly selected upon their informed consent. Data obtained/responses were analyzed using simple percentages. The chi-square test was used to assess the relationship by testing the hypothesis. Result: Results revealed that, before the seminar, a high average percentage of 72.2% (332) of respondents had not heard of cervical cancer while 27.8% (128) had heard. Of those who know about Cervical cancer, an average of 70.3% (90) showed low knowledge. The majority of respondents, 366 (79.6%), had poor attitudes toward screening. They mostly implicated lack of awareness 205 (44.6%) and lack of funds 104 (22.6%) as major reasons for not participating in the screening test. Few 128 (27.8%) agreed to go for screening and vaccination. After the awareness, 400 (87%) agreed to go for the screening test and vaccination if free/affordable. None of the participants had ever been screened. A significant relationship between attitude to cervical cancer and level of knowledge and academic level and attitude to cervical cancer screening was obtained. Conclusion: This calls for continued enlightenment about cervical cancer screening, especially as soon as sexual activity begins.

Keywords: cervical cancer, rural areas, Imo state, knowledge, attitude

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1472 Gender Differences in Communication Styles: An Analysis of the Language of Earnings Conference Calls

Authors: Chiara De Amicis, Sonia Falconieri, Mesut Tastan

Abstract:

In this study, we analyze the language employed by Chief Executive Officers (CEOs) and Chief Financial Officers (CFOs) during earnings conference calls from a gender perspective. We find evidences that conference calls held by female CEOs and/or CFOs exhibit a higher level of optimism compared to conference calls held by male CEOs and/or CFOs. Moreover, female managers tend to present and discuss firm performances with less vagueness as compared to their male colleagues. We then observe the market reaction around each earnings conference call: while manager optimism is perceived as a good signal by investors, manager vagueness significantly dampens the market reaction around the call. Whether the gender of the CEO and/or the CFO delivering the conference call affects investors’ perceptions about the firm performance is still an open question. Some evidences show that the language employed by female managers conveys more valuable information for market participants as compared to the language employed by their male counterparts. This study contributes to a growing literature in finance and accounting that uses textual analysis to assess the informativeness of corporate disclosure. To our knowledge, this is the first paper that aims at answering the question whether the gender of firm’s top managers does matter when it comes to assess the informativeness of corporate spoken communication. We believe that our results will be of relevance for future research in the field. Moreover, our evidence may be used in support of the debate if a larger participation by women in the management of companies should be encouraged or not.

Keywords: conference calls, even study, gender, market reaction, textual analysis

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1471 Efficacy of Gamma Radiation on the Productivity of Bactrocera oleae Gmelin (Diptera: Tephritidae)

Authors: Mehrdad Ahmadi, Mohamad Babaie, Shiva Osouli, Bahareh Salehi, Nadia Kalantaraian

Abstract:

The olive fruit fly, Bactrocera oleae Gmelin (Diptera: Tephritidae), is one of the most serious pests in olive orchards in growing province in Iran. The female lay eggs in green olive fruit and larvae hatch inside the fruit, where they feed upon the fruit matters. One of the main ecologically friendly and species-specific systems of pest control is the sterile insect technique (SIT) which is based on the release of large numbers of sterilized insects. The objective of our work was to develop a SIT against B. oleae by using of gamma radiation for the laboratory and field trial in Iran. Oviposition of female mated by irradiated males is one of the main parameters to determine achievement of SIT. To conclude the sterile dose, pupae were placed under 0 to 160 Gy of gamma radiation. The main factor in SIT is the productivity of females which are mated by irradiated males. The emerged adults from irradiated pupae were mated with untreated adults of the same age by confining them inside the transparent cages. The fecundity of the irradiated males mated with non-irradiated females was decreased with the increasing radiation dose level. It was observed that the number of eggs and also the percentage of the egg hatching was significantly (P < 0.05) affected in either IM x NF crosses compared with NM x NF crosses in F1 generation at all doses. Also, the statistical analysis showed a significant difference (P < 0.05) in the mean number of eggs laid between irradiated and non-irradiated females crossed with irradiated males, which suggests that the males were susceptible to gamma radiation. The egg hatching percentage declined markedly with the increase of the radiation dose of the treated males in mating trials which demonstrated that egg hatch rate was dose dependent. Our results specified that gamma radiation affects the longevity of irradiated B. oleae larvae (established from irradiated pupae) and significantly increased their larval duration. Results show the gamma radiation, and SIT can be used successfully against olive fruit flies.

Keywords: fertility, olive fruit fly, radiation, sterile insect technique

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1470 GIS Model for Sanitary Landfill Site Selection Based on Geotechnical Parameters

Authors: Hecson Christian, Joel Macwan

Abstract:

Landfill site selection in an urban area is a critical issue in the planning process. With the growth of the urbanization, it has a mammoth impact on the economy, ecology, and environmental health of the region. Outsized amount of wastes are produced and the problem gets soared every day. Hence, selection of ideal site for sanitary landfill is a challenge for urban planners and solid waste managers. Disposal site is a function of many parameters. Among all, Geotechnical parameters are very vital as the same is related to surrounding open land. Moreover, the accessible safe and acceptable land is also scarce. Therefore, in this paper geotechnical parameters are used to develop a GIS model to identify an ideal location for landfill purpose. Metropolitan city of Surat is highly populated and fastest growing urban area in India. The research objectives are to conduct field experiments to collect data and to transfer the facts in GIS platform to evolve a model, to find ideal location. Planners’ preferences were obtained to use analytical hierarchical process (AHP) to find weights of each parameter. Integration of GIS and Multi-Criteria Decision Analysis (MCDA) techniques are applied to improve decision-making. It augments an environment for transformation and combination of geographical data and planners’ preferences. GIS performs deterministic overlay and buffer operations. MCDA methods evaluate alternatives based on the decision makers’ subjective values and priorities. Research results have shown many alternative locations. Economic analysis of selected site from actual operations point of view is not included in this research.

Keywords: GIS, AHP, MCDA, Geo-technical

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1469 Supply Network Design for Production-Distribution of Fish: A Sustainable Approach Using Mathematical Programming

Authors: Nicolás Clavijo Buriticá, Laura Viviana Triana Sanchez

Abstract:

This research develops a productive context associated with the aquaculture industry in northern Tolima-Colombia, specifically in the town of Lerida. Strategic aspects of chain of fish Production-Distribution, especially those related to supply network design of an association devoted to cultivating, farming, processing and marketing of fish are addressed. This research is addressed from a special approach of Supply Chain Management (SCM) which guides management objectives to the system sustainability; this approach is called Sustainable Supply Chain Management (SSCM). The network design of fish production-distribution system is obtained for the case study by two mathematical programming models that aims to maximize the economic benefits of the chain and minimize total supply chain costs, taking into account restrictions to protect the environment and its implications on system productivity. The results of the mathematical models validated in the productive situation of the partnership under study, called Asopiscinorte shows the variation in the number of open or closed locations in the supply network that determines the final network configuration. This proposed result generates for the case study an increase of 31.5% in the partial productivity of storage and processing, in addition to possible favorable long-term implications, such as attending an agile or not a consumer area, increase or not the level of sales in several areas, to meet in quantity, time and cost of work in progress and finished goods to various actors in the chain.

Keywords: Sustainable Supply Chain, mathematical programming, aquaculture industry, Supply Chain Design, Supply Chain Configuration

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1468 Co-Design of Accessible Speech Recognition for Users with Dysarthric Speech

Authors: Elizabeth Howarth, Dawn Green, Sean Connolly, Geena Vabulas, Sara Smolley

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Through the EU Horizon 2020 Nuvoic Project, the project team recruited 70 individuals in the UK and Ireland to test the Voiceitt speech recognition app and provide user feedback to developers. The app is designed for people with dysarthric speech, to support communication with unfamiliar people and access to speech-driven technologies such as smart home equipment and smart assistants. Participants with atypical speech, due to a range of conditions such as cerebral palsy, acquired brain injury, Down syndrome, stroke and hearing impairment, were recruited, primarily through organisations supporting disabled people. Most had physical or learning disabilities in addition to dysarthric speech. The project team worked with individuals, their families and local support teams, to provide access to the app, including through additional assistive technologies where needed. Testing was user-led, with participants asked to identify and test use cases most relevant to their daily lives over a period of three months or more. Ongoing technical support and training were provided remotely and in-person throughout the testing period. Structured interviews were used to collect feedback on users' experiences, with delivery adapted to individuals' needs and preferences. Informal feedback was collected through ongoing contact between participants, their families and support teams and the project team. Focus groups were held to collect feedback on specific design proposals. User feedback shared with developers has led to improvements to the user interface and functionality, including faster voice training, simplified navigation, the introduction of gamification elements and of switch access as an alternative to touchscreen access, with other feature requests from users still in development. This work offers a case-study in successful and inclusive co-design with the disabled community.

Keywords: co-design, assistive technology, dysarthria, inclusive speech recognition

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1467 PitMod: The Lorax Pit Lake Hydrodynamic and Water Quality Model

Authors: Silvano Salvador, Maryam Zarrinderakht, Alan Martin

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Open pits, which are the result of mining, are filled by water over time until the water reaches the elevation of the local water table and generates mine pit lakes. There are several specific regulations about the water quality of pit lakes, and mining operations should keep the quality of groundwater above pre-defined standards. Therefore, an accurate, acceptable numerical model predicting pit lakes’ water balance and water quality is needed in advance of mine excavation. We carry on analyzing and developing the model introduced by Crusius, Dunbar, et al. (2002) for pit lakes. This model, called “PitMod”, simulates the physical and geochemical evolution of pit lakes over time scales ranging from a few months up to a century or more. Here, a lake is approximated as one-dimensional, horizontally averaged vertical layers. PitMod calculates the time-dependent vertical distribution of physical and geochemical pit lake properties, like temperature, salinity, conductivity, pH, trace metals, and dissolved oxygen, within each model layer. This model considers the effect of pit morphology, climate data, multiple surface and subsurface (groundwater) inflows/outflows, precipitation/evaporation, surface ice formation/melting, vertical mixing due to surface wind stress, convection, background turbulence and equilibrium geochemistry using PHREEQC and linking that to the geochemical reactions. PitMod, which is used and validated in over 50 mines projects since 2002, incorporates physical processes like those found in other lake models such as DYRESM (Imerito 2007). However, unlike DYRESM PitMod also includes geochemical processes, pit wall runoff, and other effects. In addition, PitMod is actively under development and can be customized as required for a particular site.

Keywords: pit lakes, mining, modeling, hydrology

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1466 Mitigation of Wind Loads on a Building Using Small Wind Turbines

Authors: Arindam Chowdhury, Andres Tremante, Mohammadtaghi Moravej, Bodhisatta Hajra, Ioannis Zisis, Peter Irwin

Abstract:

Extreme wind events, such as hurricanes, have caused significant damage to buildings, resulting in losses worth millions of dollars. The roof of a building is most vulnerable to wind-induced damage due to the high suctions experienced by the roof in extreme wind conditions. Wind turbines fitted to buildings can help generate energy, but to our knowledge, their application to wind load mitigation is not well known. This paper presents results from an experimental study to assess the effect of small wind turbines (developed and patented by the first and second authors) on the wind loads on a low rise building roof. The tests were carried out for an open terrain at the Wall of Wind (WOW) experimental facility at Florida International University (FIU), Miami, Florida, USA, for three cases – bare roof, roof fitted with wind turbines placed closer to the roof edges, and roof with wind turbines placed away from the roof edges. Results clearly indicate that the presence of the wind turbines reduced the mean and peak pressure coefficients (less suction) on the roof when compared to the bare deck case. Furthermore, the peak pressure coefficients were found to be lower (less suction) when the wind turbines were placed closer to the roof, than away from the roof. Flow visualization studies using smoke and gravel clearly showed that the presence of the turbines disrupted the formation of vortices formed by cornering winds, thereby reducing roof suctions and preventing lift off of roof coverings. This study shows that the wind turbines besides generating wind energy, can be used for mitigating wind induced damage to the building roof. Future research must be directed towards understanding the effect of these wind turbines on other roof geometries (e.g. hip/gable) in different terrain conditions.

Keywords: wall of wind, wind loads, wind turbine, building

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1465 Design and Development of an Autonomous Beach Cleaning Vehicle

Authors: Mahdi Allaoua Seklab, Süleyman BaşTürk

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In the quest to enhance coastal environmental health, this study introduces a fully autonomous beach cleaning machine, a breakthrough in leveraging green energy and advanced artificial intelligence for ecological preservation. Designed to operate independently, the machine is propelled by a solar-powered system, underscoring a commitment to sustainability and the use of renewable energy in autonomous robotics. The vehicle's autonomous navigation is achieved through a sophisticated integration of LIDAR and a camera system, utilizing an SSD MobileNet V2 object detection model for accurate and real-time trash identification. The SSD framework, renowned for its efficiency in detecting objects in various scenarios, is coupled with the lightweight and precise highly MobileNet V2 architecture, making it particularly suited for the computational constraints of on-board processing in mobile robotics. Training of the SSD MobileNet V2 model was conducted on Google Colab, harnessing cloud-based GPU resources to facilitate a rapid and cost-effective learning process. The model was refined with an extensive dataset of annotated beach debris, optimizing the parameters using the Adam optimizer and a cross-entropy loss function to achieve high-precision trash detection. This capability allows the machine to intelligently categorize and target waste, leading to more effective cleaning operations. This paper details the design and functionality of the beach cleaning machine, emphasizing its autonomous operational capabilities and the novel application of AI in environmental robotics. The results showcase the potential of such technology to fill existing gaps in beach maintenance, offering a scalable and eco-friendly solution to the growing problem of coastal pollution. The deployment of this machine represents a significant advancement in the field, setting a new standard for the integration of autonomous systems in the service of environmental stewardship.

Keywords: autonomous beach cleaning machine, renewable energy systems, coastal management, environmental robotics

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1464 Language and Culture Exchange: Tandem Language Learning for University Students

Authors: Hebe Wong, Luz Fernandez Calventos

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Tandem language learning, a language exchange process based on the principles of autonomy and reciprocity, provides opportunities for interlocutors to learn each other’s language by communicating online or face-to-face. While much attention has been paid to the process and outcomes of tandem learning via email, little has been discussed about the effectiveness of face-to-face tandem learning on language and culture exchange for university students. The LACTS (Language and Culture Tandem Scheme), an 8-week project, was set up to study students’ perceptions of conducting tandem learning to assist their language and culture exchange. Students of both post-graduate and undergraduate programmes (N=103) from a Hong Kong SAR university were put in groups of 4 to 6 according to their availability and language preferences and met for an hour a week. While sample task sheets on a range of topics were provided to assist the language exchange, all groups were encouraged to take charge of their meeting format and choose their own topics. At the end of the project, a 19-item questionnaire, which included both open-and closed-ended questions investigating students’ perceptions of reciprocal teaching and cultural exchange, was administered. Thirty-minute individual interviews were conducted to elicit students’ views and experiences in the LACTS activities. Quantitative and qualitative data analysis showed that most students agreed that the project had enhanced their cultural awareness and helped create an inclusive and participatory learning environment. Significant differences were found in students’ confidence in speaking their targeted language after joining the scheme. The interviews also provided rich data on the variety of formats and leadership patterns in student-led meetings, which could shed light on student autonomy and future tandem language learning projects.

Keywords: autonomy, reciprocity, tandem language learning, university students

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1463 A Comparative Study of Dengue Fever in Taiwan and Singapore Based on Open Data

Authors: Wei Wen Yang, Emily Chia Yu Su

Abstract:

Dengue fever is a mosquito-borne tropical infectious disease caused by the dengue virus. After infection, symptoms usually start from three to fourteen days. Dengue virus may cause a high fever and at least two of the following symptoms, severe headache, severe eye pain, joint pains, muscle or bone pain, vomiting, feature skin rash, and mild bleeding manifestation. In addition, recovery will take at least two to seven days. Dengue fever has rapidly spread in tropical and subtropical areas in recent years. Several phenomena around the world such as global warming, urbanization, and international travel are the main reasons in boosting the spread of dengue. In Taiwan, epidemics occur annually, especially during summer and fall seasons. On the other side, Singapore government also has announced the amounts number of dengue cases spreading in Singapore. As the serious epidemic of dengue fever outbreaks in Taiwan and Singapore, countries around the Asia-Pacific region are becoming high risks of susceptible to the outbreaks and local hub of spreading the virus. To improve public safety and public health issues, firstly, we are going to use Microsoft Excel and SAS EG to do data preprocessing. Secondly, using support vector machines and decision trees builds predict model, and analyzes the infectious cases between Taiwan and Singapore. By comparing different factors causing vector mosquito from model classification and regression, we can find similar spreading patterns where the disease occurred most frequently. The result can provide sufficient information to predict the future dengue infection outbreaks and control the diffusion of dengue fever among countries.

Keywords: dengue fever, Taiwan, Singapore, Aedes aegypti

Procedia PDF Downloads 239
1462 Groundwater Treatment of Thailand's Mae Moh Lignite Mine

Authors: A. Laksanayothin, W. Ariyawong

Abstract:

Mae Moh Lignite Mine is the largest open-pit mine in Thailand. The mine serves coal to the power plant about 16 million tons per year. This amount of coal can produce electricity accounting for about 10% of Nation’s electric power generation. The mining area of Mae Moh Mine is about 28 km2. At present, the deepest area of the pit is about 280 m from ground level (+40 m. MSL) and in the future the depth of the pit can reach 520 m from ground level (-200 m.MSL). As the size of the pit is quite large, the stability of the pit is seriously important. Furthermore, the preliminary drilling and extended drilling in year 1989-1996 had found high pressure aquifer under the pit. As a result, the pressure of the underground water has to be released in order to control mine pit stability. The study by the consulting experts later found that 3-5 million m3 per year of the underground water is needed to be de-watered for the safety of mining. However, the quality of this discharged water should meet the standard. Therefore, the ground water treatment facility has been implemented, aiming to reduce the amount of naturally contaminated Arsenic (As) in discharged water lower than the standard limit of 10 ppb. The treatment system consists of coagulation and filtration process. The main components include rapid mixing tanks, slow mixing tanks, sedimentation tank, thickener tank and sludge drying bed. The treatment process uses 40% FeCl3 as a coagulant. The FeCl3 will adsorb with As(V), forming floc particles and separating from the water as precipitate. After that, the sludge is dried in the sand bed and then be disposed in the secured land fill. Since 2011, the treatment plant of 12,000 m3/day has been efficiently operated. The average removal efficiency of the process is about 95%.

Keywords: arsenic, coagulant, ferric chloride, groundwater, lignite, coal mine

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1461 Quantitative Evaluation on Community Perceptions of Sanitation and Hygiene in Rural Guatemala

Authors: Akudo Ejelonu, Sarah Willig, J. Anthony Sauder, Heather Murphy, Frances Shofer

Abstract:

Background: The high prevalence of diarrheal diseases in the village of Tzununá, Guatemala is linked to lack of sanitation facilities and handwashing practices. Diarrheal diseases are preventable and improved access to latrines, hygiene education and clean water may improve sanitation by reducing the spread of disease. Objective: Between May 2015-January 2017, the University of Pennsylvania Chapter of Engineers Without Border (PennEWB) and local partners designed an intervention to reduce diarrheal disease by building pour flush latrines in 50 individual households and providing education on the importance of handwashing practice. Design/Methods: Through convenient sampling, we surveyed 45 households to evaluate the community’s knowledge of diarrheal disease, handwashing practices, and maintenance of the latrines. Results: 92% of the study participants experienced decrease of new cases of diarrheal disease after receiving a latrine. Only 11% washed their hands after defecating in the latrine. There was gap in understanding the health outcome of latrine sanitation and handwashing education. The respondents did not connect the reduction of diarrheal disease with latrine use and maintenance. Instead, they associated their motivation for latrine use with aesthetics, proximity to their home, ease and comfort, and reduction of shame. We recommend that PennEWB adopt UNICEF or WHO education on hand washing practice. Conclusion: Social interaction and social pressure drove the household use of latrines. The latrines are being valued and cleaned. The education that the residents received did not target norms and behaviors. Latrines could be used to create a new social norm that supports behavioral change.

Keywords: diarrheal disease, latrine, open defecation, water, sanitation and hygiene

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1460 Improvement of Water Quality of Al Asfar Lake Using Constructed Wetland System

Authors: Jamal Radaideh

Abstract:

Al-Asfar Lake is located about 14 km east of Al-Ahsa and is one of the most important wetland lakes in the Al Ahsa/Eastern Province of Saudi Arabia. Al-Ahsa is may be the largest oasis in the world, having an area of 20,000 hectares, in addition, it is of the largest and oldest agricultural centers in the region. The surplus farm irrigation water beside additional water supplied by treated wastewater from Al-Hofuf sewage station is collected by a drainage network and discharged into Al-Asfar Lake. The lake has good wetlands, sand dunes as well as large expanses of open and shallow water. Salt tolerant vegetation is present in some of the shallow areas around the lake, and huge stands of Phragmites reeds occur around the lake. The lake presents an important habitat for wildlife and birds, something not expected to find in a large desert. Although high evaporation rates in the range of 3250 mm are common, the water remains in the evaporation lakes during all seasons of the year is used to supply cattle with drinking water and for aquifer recharge. Investigations showed that high concentrations of nitrogen (N), phosphorus (P), biological oxygen demand (BOD), chemical oxygen demand (COD) and salinity discharge to Al Asfar Lake from the D2 drain exist. It is expected that the majority of BOD, COD and N originates from wastewater discharge and leachate from surplus irrigation water which also contribute to the majority of P and salinity. The significant content of nutrients and biological oxygen demand reduces available oxygen in the water. The present project aimed to improve the water quality of the lake using constructed wetland trains which will be built around the lake. Phragmites reeds, which already occur around the lake, will be used.

Keywords: Al Asfar lake, constructed wetland, water quality, water treatment

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1459 Assessment of the Effect of Farmer-Herder Conflict on the Livelihood of Rural Households in Bogoro Local Government Area of Bauchi State, Nigeria

Authors: Luka Jumma Gizaki

Abstract:

The study assessed the effect of farmer-herder conflict on the livelihood of rural households in Bogoro L.G.A., Bauchi State, Nigeria. Multistage sampling procedures were used to randomly select 66 crop farmers in the study area. Data were collected by means of a structured questionnaire. The result was analyzed using descriptive and inferential statistics. Results showed that the majority of the respondents were males with a mean age of 39 years and a farming experience of 16 years. About 95% of the respondents had formal education, with a mean household size of 8 persons per household. Farmer-herder conflicts were found to be caused by grazing on growing crops, wrong approach by farmers in raising complaints and harassment of herdsmen, absence of grazing route and poisoning of uncultivated lands. Constraints to resolving conflict were found to include personal interest, lack of government will, ethnicity and religious difference and open grazing ranking first, second and third, among others. Six factors connected to farmer-herder conflict were found to significantly affect the livelihood of rural households. These were the value of crops destroyed, the number of livestock lost, and the cost of treatment of wounds sustained from the conflict. The value of crops and the size of farmland abandoned in fear were significant, and the cost of seeking redress was significant at P≤0.01. It was concluded that farmer-herder conflict impacts negatively not only crops and animals but also affects the lives of farmers and herders as well as their economy. It is recommended that proper methods be adopted to avoid its occurrence, and when it occurs, the erring party should be appropriately punished.

Keywords: farmer, herder, conflict, effect, coping

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1458 Analyzing Use of Figurativeness, Visual Elements, Allegory, Scenic Imagery as Support System in Punjabi Contemporary Theatre for Escaping Censorship

Authors: Shazia Anwer

Abstract:

This paper has discussed the unusual form of resistance in theatre against censorship board in Pakistan. The atypical approach of dramaturgy created massive space for performers and audiences to integrate and communicate. The social and religious absolutes creates suffocation in Pakistani society, strict control over all Fine and Performing Art has made art political, contemporary dramatics has started an amalgamated theatre to avoid censorship. Contemporary Punjabi theatre techniques are directly dependent on human cognition. The idea of indirect thought processing is not unique but dependent on spectators. The paper has provided an account of these techniques and their specific use for conveying specific messages across the audiences. For the Dramaturge of today, theatre space is an expression representing a linguistic formulation that includes qualities of experimental and non-traditional use of classical theatrical space in the context of fulfilling the concept of open theatre. Paper has explained the transformation of the theatrical experience into an event where the actor and the audience are co-existing and co-experiencing the dramatical experience. The denial of the existence of the 4th -Wall made two-way communication possible. This paper has elaborated that the previously marginalized genres such as naach, jugat, miras, are extensively included to counter the censorship board. Figurativeness, visual elements, allegory, scenic imagery are basic support system for contemporary Punjabi theatre. The body of the actor is used as a source for non-verbal communication, and for an escape from traditional theatrical space which by every means has every element that could be controlled and reprimanded by the controlling authority.

Keywords: communication, Punjabi theatre, figurativeness, censorship

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1457 Identification of the Expression of Top Deregulated MiRNAs in Rheumatoid Arthritis and Osteoarthritis

Authors: Hala Raslan, Noha Eltaweel, Hanaa Rasmi, Solaf Kamel, May Magdy, Sherif Ismail, Khalda Amr

Abstract:

Introduction: Rheumatoid arthritis (RA) is an inflammatory, autoimmune disorder with progressive joint damage. Osteoarthritis (OA) is a degenerative disease of the articular cartilage that shows multiple clinical manifestations or symptoms resembling those of RA. Genetic predisposition is believed to be a principal etiological factor for RA and OA. In this study, we aimed to measure the expression of the top deregulated miRNAs that might be the cause of pathogenesis in both diseases, according to our latest NGS analysis. Six of the deregulated miRNAs were selected as they had multiple target genes in the RA pathway, so they are more likely to affect the RA pathogenesis.Methods: Eighty cases were recruited in this study; 45 rheumatoid arthiritis (RA), 30 osteoarthiritis (OA) patients, as well as 20 healthy controls. The selection of the miRNAs from our latest NGS study was done using miRwalk according to the number of their target genes that are members in the KEGG RA pathway. Total RNA was isolated from plasma of all recruited cases. The cDNA was generated by the miRcury RT Kit then used as a template for real-time PCR with miRcury Primer Assays and the miRcury SYBR Green PCR Kit. Fold changes were calculated from CT values using the ΔΔCT method of relative quantification. Results were compared RA vs Controls and OA vs Controls. Target gene prediction and functional annotation of the deregulated miRNAs was done using Mienturnet. Results: Six miRNAs were selected. They were miR-15b-3p, -128-3p, -194-3p, -328-3p, -542-3p and -3180-5p. In RA samples, three of the measured miRNAs were upregulated (miR-194, -542, and -3180; mean Rq= 2.6, 3.8 and 8.05; P-value= 0.07, 0.05 and 0.01; respectively) while the remaining 3 were downregulated (miR-15b, -128 and -328; mean Rq= 0.21, 0.39 and 0.6; P-value= <0.0001, <0.0001 and 0.02; respectively) all with high statistical significance except miR-194. While in OA samples, two of the measured miRNAs were upregulated (miR-194 and -3180; mean Rq= 2.6 and 7.7; P-value= 0.1 and 0.03; respectively) while the remaining 4 were downregulated (miR-15b, -128, -328 and -542; mean Rq= 0.5, 0.03, 0.08 and 0.5; P-value= 0.0008, 0.003, 0.006 and 0.4; respectively) with statistical significance compared to controls except miR-194 and miR-542. The functional enrichment of the selected top deregulated miRNAs revealed the highly enriched KEGG pathways and GO terms. Conclusion: Five of the studied miRNAs were greatly deregulated in RA and OA, they might be highly involved in the disease pathogenesis and so might be future therapeutic targets. Further functional studies are crucial to assess their roles and actual target genes.

Keywords: MiRNAs, expression, rheumatoid arthritis, osteoarthritis

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1456 Nutriscience Project: A Web-Based Intervention to Improve Nutritional Literacy among Families and Educators of Pre-School Children

Authors: R. Barros, J. Azevedo, P. Padrão, M. Gregório, I. Pádua, C. Almeida, C. Rodrigues, P. Fontes, A. Coelho

Abstract:

Recent evidence shows a positive association between nutritional literacy and healthy eating. Traditional nutrition education strategies for childhood obesity prevention have shown weak effect. The Nutriscience project aims to create and evaluate an innovative and multidisciplinary strategy for promoting effective and accessible nutritional information to children, their families, and educators. Nutriscience is a one-year prospective follow-up evaluation study including pre-school children (3-5 y), who attend national schools’ network (29). The project is structured around a web-based intervention, using an on-line interactive platform, and focus on increasing fruit and vegetable consumption, and reducing sugar and salt intake. The platform acts as a social network where educational materials, games, and nutritional challenges are proposed in a gamification approach that promotes family and community social ties. A nutrition Massive Online Open Course is developed for educators, and a national healthy culinary contest will be promoted on TV channel. A parental self-reported questionnaire assessing sociodemographic and nutritional literacy (knowledge, attitudes, skills) is administered (baseline and end of the intervention). We expect that results on nutritional literacy from the presented strategy intervention will give us important information about the best practices for health intervention with kindergarten families. This intervention program using a digital interactive platform could be an educational tool easily adapted and disseminated for childhood obesity prevention.

Keywords: childhood obesity, educational tool, nutritional literacy, web-based intervention

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1455 English Language Teachers' Perceptions of Educational Research

Authors: Pinar Sali, Esim Gursoy, Ebru Atak Damar

Abstract:

Teachers’ awareness of and involvement in educational research (ER) is regarded as an indispensable aspect of professional growth and development. It is also believed to be a catalyst for effective teaching and learning. This strong emphasis on the significance of teacher research engagement has sparked inquiry into how teachers construe ER and whether or not they practice it. However, there seems to exist a few researches on teachers’ perceptions of and experience with ER in the field of English Language Teaching (ELT). The present study thus attempts to fill this gap in the ELT literature and aims to unearth English language teachers’ perceptions of ER. Understanding these perceptions would undoubtedly aid in the development of strategies to promote teacher interest and involvement in research. The participants of the present study are 70 English language teachers in public and private schools in Turkey. A mixed-method approach has been used in the study. Both qualitative and quantitative data have been gathered by means of a questionnaire consisting of two parts. The first part of the questionnaire consists of 20 close-ended items of Teachers’ Attitude Scale Towards Educational Research (TASTER). The second part of the questionnaire has been developed by the researchers via an extensive literature review and consists of a mixture of close- and open-ended questions. In addition, 15 language teachers have been interviewed for an in-depth understanding of the results. Descriptive statistics and dual comparisons have been employed for the quantitative data, and the qualitative data have been analyzed by means of content analysis. The present study provides intriguing information as to the English language teachers’ perceptions of the usefulness and practicality of ER as well as the value they attain to it. The findings are discussed in relation to language teacher education. The research has implications for the teacher education process, teacher trainers and policy makers.

Keywords: attitudes toward educational research, educational research, language teachers, teacher research

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1454 Matching Coping Strategies to Athletic Retirement Stressors among Japanese Female Athletes

Authors: Miyako Oulevey, David Lavallee, Naohiko Kohtake

Abstract:

Retirement from sport can be stressful to athletes for many reasons. Accordingly, it is necessary to match coping strategies depending on the stressors. One of the athlete career assistance programs for Japanese top athletes in Japan, the Japan Olympic Committee Career Academy (JCA), has focused on the service contents regarding occupational supports which can be said to cope with financial and occupational stress; however, other supports such as psychological support were unclear due to the lack of psychological professionals in the JCA. Tailoring the program, it is important to match the needs of the athletes at athletic retirement with the service contents. Japanese Olympic athletes have been found to retire for different reasons. Especially female athletes who competed in the Summer Olympic Games were found to retire with psychological reasons. The purpose of this research was to investigate the types of stressors Japanese female athletes experience as a result of athletic retirement. As part of the study, 44 female retired athletes from 13 competitive sports completed an open-ended questionnaire. The KJ method was used to analyze stress experienced as a result of retirement. As a result, nine conceptualized stressors were aggregated such as “Conflict with athletic identity”, “Desire to live as an athlete”, and “Career plan after retirement”. In order to match the coping strategies according to the stressors, each stressor was classified with the four types of adjustments; psychological, social, financial, and occupational changes. As a result, the stressor relating to psychological adjustment accounted for 69.0% of coping-related needs, the financial and occupational adjustment was 21.8%, and social adjustment was 9.2%. In conclusion, coping strategies according to the stressors are suggested.

Keywords: athletic retirement, coping, female athlete, stress

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1453 Mn3O4-NiFe Layered Double Hydroxides(LDH)/Carbon Composite Cathode for Rechargeable Zinc-Air Battery

Authors: L. K. Nivedha, V. Maruthapandian, R. Kothandaraman

Abstract:

Rechargeable zinc-air batteries (ZAB) are gaining significant research attention owing to their high energy density and copious zinc resources worldwide. However, the unsolved obstacles such as dendrites, passivation, depth of discharge and the lack of an efficient cathode catalyst restrict their practical application1. By and large, non-noble transition metal-based catalysts are well-reputed materials for catalysing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with greater stability in alkaline medium2. Herein, we report the synthesis and application of Mn₃O4-NiFeLDH/Carbon composite as a cathode catalyst for rechargeable ZAB. The synergetic effects of the mixed transition metals (Mn/Ni/Fe) have aided in catalysing ORR and OER in alkaline electrolyte with a shallow potential gap of 0.7 V. The composite, by its distinctive physicochemical characteristics, shows an excellent OER activity with a current density of 1.5 mA cm⁻² at a potential of 1.6 V and a superior ORR activity with an onset potential of 0.8 V when compared with their counterparts. Nevertheless, the catalyst prefers a two-electron pathway for the electrochemical reduction of oxygen which results in a limiting current density of 2.5 mA cm⁻². The bifunctional activity of the Mn₃O₄-NiFeLDH/Carbon composite was utilized in developing rechargeable ZAB. The fully fabricated ZAB delivers an open circuit voltage of 1.4 V, a peak power density of 70 mW cm⁻², and a specific capacity of 800 mAh g⁻¹ at a current density of 20 mA cm⁻² with an average discharge voltage of 1 V and the cell is operable upto 50 mA cm-2. Rechargeable ZAB demonstrated over 110 h at 10 mA cm⁻². Further, the cause for the diminished charge-discharge performance experienced beyond the 100th cycle was investigated, and carbon corrosion was testified using Infrared spectroscopy.

Keywords: rechargeable zinc-air battery, oxygen evolution reaction, bifunctional catalyst, alkaline medium

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1452 Self-Regulated Learning: A Required Skill for Web 2.0 Internet-Based Learning

Authors: Pieter Conradie, M. Marina Moller

Abstract:

Web 2.0 Internet-based technologies have intruded all aspects of human life. Presently, this phenomenon is especially evident in the educational context, with increased disruptive Web 2.0 technology infusions dramatically changing educational practice. The most prominent of these Web 2.0 intrusions can be identified as Massive Open Online Courses (Coursera, EdX), video and photo sharing sites (Youtube, Flickr, Instagram), and Web 2.0 online tools utilize to create Personal Learning Environments (PLEs) (Symbaloo (aggregator), Delicious (social bookmarking), PBWorks (collaboration), Google+ (social networks), Wordspress (blogs), Wikispaces (wiki)). These Web 2.0 technologies have supported the realignment from a teacher-based pedagogy (didactic presentation) to a learner-based pedagogy (problem-based learning, project-based learning, blended learning), allowing greater learner autonomy. No longer is the educator the source of knowledge. Instead the educator has become the facilitator and mediator of the learner, involved in developing learner competencies to support life-long learning (continuous learning) in the 21st century. In this study, the self-regulated learning skills of thirty first-year university learners were explored by utilizing the Online Self-regulated Learning Questionnaire. Implementing an action research method, an intervention was affected towards improving the self-regulation skill set of the participants. Statistical significant results were obtained with increased self-regulated learning proficiency, positively impacting learner performance. Goal setting, time management, environment structuring, help seeking, task (learning) strategies and self-evaluation skills were confirmed as determinants of improved learner success.

Keywords: andragogy, online self-regulated learning questionnaire, self-regulated learning, web 2.0

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