Search results for: Samuel Francisco Ngovene
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 425

Search results for: Samuel Francisco Ngovene

155 D6tions: A Serious Game to Learn Software Engineering Process and Design

Authors: Hector G. Perez-Gonzalez, Miriam Vazquez-Escalante, Sandra E. Nava-Muñoz, 
 Francisco E. Martinez-Perez, Alberto S. Nunez-Varela

Abstract:

The software engineering teaching process has been the subject of many studies. To improve this process, researchers have proposed merely illustrative techniques in the classroom, such as topic presentations and dynamics between students on one side or attempts to involve students in real projects with companies and institutions to bring them to a real software development problem on the other hand. Simulators and serious games have been used as auxiliary tools to introduce students to topics that are too abstract when these are presented in the traditional way. Most of these tools cover a limited area of the huge software engineering scope. To address this problem, we have developed D6tions, an educational serious game that simulates the software engineering process and is designed to experiment the different stages a software engineer (playing roles as project leader or as a developer or designer) goes through, while participating in a software project. We describe previous approaches to this problem, how D6tions was designed, its rules, directions, and the results we obtained of the use of this game involving undergraduate students playing the game.

Keywords: serious games, software engineering, software engineering education, software engineering teaching process

Procedia PDF Downloads 454
154 Poultry in Motion: Text Mining Social Media Data for Avian Influenza Surveillance in the UK

Authors: Samuel Munaf, Kevin Swingler, Franz Brülisauer, Anthony O’Hare, George Gunn, Aaron Reeves

Abstract:

Background: Avian influenza, more commonly known as Bird flu, is a viral zoonotic respiratory disease stemming from various species of poultry, including pets and migratory birds. Researchers have purported that the accessibility of health information online, in addition to the low-cost data collection methods the internet provides, has revolutionized the methods in which epidemiological and disease surveillance data is utilized. This paper examines the feasibility of using internet data sources, such as Twitter and livestock forums, for the early detection of the avian flu outbreak, through the use of text mining algorithms and social network analysis. Methods: Social media mining was conducted on Twitter between the period of 01/01/2021 to 31/12/2021 via the Twitter API in Python. The results were filtered firstly by hashtags (#avianflu, #birdflu), word occurrences (avian flu, bird flu, H5N1), and then refined further by location to include only those results from within the UK. Analysis was conducted on this text in a time-series manner to determine keyword frequencies and topic modeling to uncover insights in the text prior to a confirmed outbreak. Further analysis was performed by examining clinical signs (e.g., swollen head, blue comb, dullness) within the time series prior to the confirmed avian flu outbreak by the Animal and Plant Health Agency (APHA). Results: The increased search results in Google and avian flu-related tweets showed a correlation in time with the confirmed cases. Topic modeling uncovered clusters of word occurrences relating to livestock biosecurity, disposal of dead birds, and prevention measures. Conclusions: Text mining social media data can prove to be useful in relation to analysing discussed topics for epidemiological surveillance purposes, especially given the lack of applied research in the veterinary domain. The small sample size of tweets for certain weekly time periods makes it difficult to provide statistically plausible results, in addition to a great amount of textual noise in the data.

Keywords: veterinary epidemiology, disease surveillance, infodemiology, infoveillance, avian influenza, social media

Procedia PDF Downloads 71
153 Ensuring Continuity in Subcutaneous Depot Medroxy Progesterone Acetate (DMPA-SC) Contraception Service Provision Using Effective Commodity Management Practices

Authors: Oluwaseun Adeleke, Samuel O. Ikani, Fidelis Edet, Anthony Nwala, Mopelola Raji, Simeon Christian Chukwu

Abstract:

Background: The Delivering Innovations in Selfcare (DISC) project aims to increase access to self-care options for women of reproductive age, starting with self-inject subcutaneous depot medroxyprogesterone acetate (DMPA-SC) contraception services. However, the project has faced challenges in ensuring the continuous availability of the commodity in health facilities. Although most states in the country rely on the federal ministry of Health for supplies, some are gradually funding the procurement of Family Planning (FP) commodities. This attempt is, however, often accompanied by procurement delays and purchases inadequate to meet demand. This dilemma was further exacerbated by the commencement of demand generation activities by the project in supported states which geometrically increased commodity utilization rates and resulted in receding stock and occasional service disruptions. Strategies: The project deployed various strategies were implemented to ensure the continuous availability of commodities. These include facilitating inter-facility transfer, monthly tracking of commodity utilization, and alerting relevant authorities when stock levels reach a minimum. And supporting state-level procurement of DMPA-SC commodities through catalytic interventions. Results: Effective monitoring of commodity inventory at the facility level and strategic engagement with federal and state-level logistics units have proven successful in mitigating stock-out of commodities. It has helped secure up to 13,000 units of DMPA-SC commodities from federal logistics units and enabled state units to prioritize supported sites. This has ensured the continuity of DMPA-SC services and an increasing trend in the practice of self-injection. Conclusion: A functional supply chain is crucial to achieving commodity security, and without it, health programs cannot succeed. Stakeholder engagement, stock management and catalytic interventions have provided both short- and long-term measures to mitigate stock-outs and ensured a consistent supply of commodities to clients.

Keywords: family planning, contraception, DMPA-SC, self-care, self-injection, commodities, stock-out

Procedia PDF Downloads 51
152 Nigerian Media Coverage of the Chibok Girls Kidnap: A Qualitative News Framing Analysis of the Nation Newspaper

Authors: Samuel O. Oduyela

Abstract:

Over the last ten years, many studies have examined the media coverage of terrorism across the world. Nevertheless, most of these studies have been inclined to the western narrative, more so in relation to the international media. This study departs from that partiality to explore the Nigerian press and its coverage of the Boko Haram. The study intends to illustrate how the Nigerian press has reported its homegrown terrorism within its borders. On 14 April 2014, the Shekau-led Boko Haram kidnapped over 200 female students from Chibok in the Borno State. This study analyses a structured sample of news stories, feature articles, editorial comments, and opinions from the Nation newspaper. The study examined the representation of the Chibok girls kidnaps by concentrating on four main viewpoints. The news framing of the Chibok girls’ kidnap under Presidents Goodluck Jonathan (2014) and Mohammadu Buhari (2016-2018), the sourcing model present in the news reporting of the kidnap and the challenges Nation reporters face in reporting Boko Haram. The study adopted the use of qualitative news framing analysis to provide further insights into significant developments established from the examination of news contents. The study found that the news reportage mainly focused on the government response to Chibok girls kidnap, international press and Boko Haram. Boko Haram was also framed, as a political conspiracy, as prevailing, and as instilling fear. Political, and economic influence appeared to be a significant determinant of the reportage. The study found that the Nation newspaper's portrayal of the crisis under President Jonathan differed significantly from under President Buhari. While the newspaper framed the action of President Jonathan as lacklustre, dismissive, and confusing, it was less critical of President Buhari's government's handling of the crisis. The Nation newspaper failed to promote or explore non-violent approaches. News reports of the kidnap, thus, were presented mainly from a political and ethnoreligious perspective. The study also raised questions of what roles should journalists play in covering conflicts? Should they merely report comments on and interpret it, or should they be actors in the resolution or, more importantly, the prevention of conflicts? The study underlined the need for the independence of the media, more training for journalists to advance a more nuanced and conflict-sensitive news coverage in the Nigerian context.

Keywords: boko haram, chibok girls kidnap, conflict in nigeria, media framing

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151 Methodology for Developing an Intelligent Tutoring System Based on Marzano’s Taxonomy

Authors: Joaquin Navarro Perales, Ana Lidia Franzoni Velázquez, Francisco Cervantes Pérez

Abstract:

The Mexican educational system faces diverse challenges related with the quality and coverage of education. The development of Intelligent Tutoring Systems (ITS) may help to solve some of them by helping teachers to customize their classes according to the performance of the students in online courses. In this work, we propose the adaptation of a functional ITS based on Bloom’s taxonomy called Sistema de Apoyo Generalizado para la Enseñanza Individualizada (SAGE), to measure student’s metacognition and their emotional response based on Marzano’s taxonomy. The students and the system will share the control over the advance in the course, so they can improve their metacognitive skills. The system will not allow students to get access to subjects not mastered yet. The interaction between the system and the student will be implemented through Natural Language Processing techniques, thus avoiding the use of sensors to evaluate student’s response. The teacher will evaluate student’s knowledge utilization, which is equivalent to the last cognitive level in Marzano’s taxonomy.

Keywords: intelligent tutoring systems, student modelling, metacognition, affective computing, natural language processing

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150 Understanding Evolutionary Algorithms through Interactive Graphical Applications

Authors: Javier Barrachina, Piedad Garrido, Manuel Fogue, Julio A. Sanguesa, Francisco J. Martinez

Abstract:

It is very common to observe, especially in Computer Science studies that students have difficulties to correctly understand how some mechanisms based on Artificial Intelligence work. In addition, the scope and limitations of most of these mechanisms are usually presented by professors only in a theoretical way, which does not help students to understand them adequately. In this work, we focus on the problems found when teaching Evolutionary Algorithms (EAs), which imitate the principles of natural evolution, as a method to solve parameter optimization problems. Although this kind of algorithms can be very powerful to solve relatively complex problems, students often have difficulties to understand how they work, and how to apply them to solve problems in real cases. In this paper, we present two interactive graphical applications which have been specially designed with the aim of making Evolutionary Algorithms easy to be understood by students. Specifically, we present: (i) TSPS, an application able to solve the ”Traveling Salesman Problem”, and (ii) FotEvol, an application able to reconstruct a given image by using Evolution Strategies. The main objective is that students learn how these techniques can be implemented, and the great possibilities they offer.

Keywords: education, evolutionary algorithms, evolution strategies, interactive learning applications

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149 Application of Nuclear Magnetic Resonance (1H-NMR) in the Analysis of Catalytic Aquathermolysis: Colombian Heavy Oil Case

Authors: Paola Leon, Hugo Garcia, Adan Leon, Samuel Munoz

Abstract:

The enhanced oil recovery by steam injection was considered a process that only generated physical recovery mechanisms. However, there is evidence of the occurrence of a series of chemical reactions, which are called aquathermolysis, which generates hydrogen sulfide, carbon dioxide, methane, and lower molecular weight hydrocarbons. These reactions can be favored by the addition of a catalyst during steam injection; in this way, it is possible to generate the original oil in situ upgrading through the production increase of molecules of lower molecular weight. This additional effect could increase the oil recovery factor and reduce costs in transport and refining stages. Therefore, this research has focused on the experimental evaluation of the catalytic aquathermolysis on a Colombian heavy oil with 12,8°API. The effects of three different catalysts, reaction time, and temperature were evaluated in a batch microreactor. The changes in the Colombian heavy oil were quantified through nuclear magnetic resonance 1H-NMR. The relaxation times interpretation and the absorption intensity allowed to identify the distribution of the functional groups in the base oil and upgraded oils. Additionally, the average number of aliphatic carbons in alkyl chains, the number of substituted rings, and the aromaticity factor were established as average structural parameters in order to simplify the samples' compositional analysis. The first experimental stage proved that each catalyst develops a different reaction mechanism. The aromaticity factor has an increasing order of the salts used: Mo > Fe > Ni. However, the upgraded oil obtained with iron naphthenate tends to form a higher content of mono-aromatic and lower content of poly-aromatic compounds. On the other hand, the results obtained from the second phase of experiments suggest that the upgraded oils have a smaller difference in the length of alkyl chains in the range of 240º to 270°C. This parameter has lower values at 300°C, which indicates that the alkylation or cleavage reactions of alkyl chains govern at higher reaction temperatures. The presence of condensation reactions is supported by the behavior of the aromaticity factor and the bridge carbons production between aromatic rings (RCH₂). Finally, it is observed that there is a greater dispersion in the aliphatic hydrogens, which indicates that the alkyl chains have a greater reactivity compared to the aromatic structures.

Keywords: catalyst, upgrading, aquathermolysis, steam

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148 Self-Efficacy and Self-Worth of Elderly in Geriatric Institutions

Authors: Melasurej C. Francisco, Sophia D. Rusit

Abstract:

Old age is a record of one’s own life; this is the crucial phase for most. However, there are individuals who believe that old people retain self-efficacy and self-worth throughout their existence. Geriatric institutions focus on the health of elderly, in which they have been supported with medicines and therapies by clinician thus, indicating that these may suffice physical, emotional, and mental health of the elderly. This study focuses on (1) Describing the level or degree of self-efficacy; (2) Recognizing the extent of self-worth; (3) Determining the significant relationship between self-efficacy and self-worth. It is a mixed method design. A combination of correlational research and in-depth interview. Purposive sampling technique was used to select participants, considering that this assay focused on elderly in geriatric institutions, it follows that respondents and participants are at least sixty years of age and must be living inside the institution. 121 senior citizens took part in this study. Scores from both General Self-Efficacy Scale (GSE) and Rosenberg Self-Esteem Scale (RSES) showed varying levels of self-efficacy and self-worth. SE had μ=28.099, σ=6.6262, σ²=43.9067 while; SW had μ=14.9669, σ=5.3789, σ²28.9322 which denotes that rₒbₜ (121)=0.3164 is higher than rcᵢₜ which is 0.150. Although this exhibits the positive moderate correlation between SE and SW, the relationship between variables is weak. Likewise, the pᵥₐₗᵤₑ (pᵥₐₗᵤₑ=0.000406) is lower than the significance level alpha=0.01, thus, rejecting the null hypothesis, and accepting the alternative hypothesis.

Keywords: elderly, geriatric, self-efficacy, self-worth

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147 The Clash of the Clans in the British Divorce

Authors: Samuel Gary Beckton

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Ever since the Scottish Independence Referendum in 2014, there has been a threat of a second referendum. However, if there was another referendum and the majority favoured independence, it is highly likely to be by a small majority. In this paper, it will look into the hypothetical situation of what could have happened if Scotland had voted in favour of independence in 2014. If this occurred, there would be many Unionists within Scotland, including devoted supporters of the Better Together campaign. There was a possibility of some Scottish Unionists not willing to accept the result of the Referendum unchallenged and use their right of self-determination through the UN Charter for their region to remain within the United Kingdom. The Shetland and Orkney Islands contemplated of opting out of an independent Scotland in 2013. This caught the attention of some politicians and the media, via confirming the possibility of some form of partition in Scotland and could have gained extra attention if partition quickly became a matter of ‘need’ instead of ‘want’. Whilst some Unionists may have used petitions and formed pressure groups to voice their claims, others may have used more hard-line tactics to achieve their political objectives, including possible protest marches and acts of civil unrest. This could have possibly spread sectarian violence between Scottish Unionists and Nationalists. Glasgow has a serious issue of this kind of sectarianism, which has escalated in recent years. This is due to the number communities that have been established from Irish Immigrants, which maintain links with Northern Irish loyalists and republicans. Some Scottish Unionists not only have sympathy towards Northern Irish loyalists but actively participate with the paramilitary groups and gave support. Scottish loyalists could use these contacts to create their own paramilitary group(s), with aid from remaining UK (RUK) benefactors. Therefore, this could have resulted in the RUK facing a serious security dilemma, with political and ethical consequences to consider. The RUK would have the moral obligation to protect Scottish Unionists from persecution and recognise their right of self-determination, whilst ensuring the security and well-being of British citizens within and outside of Scotland. This work takes into consideration the lessons learned from the ‘Troubles’ in Northern Ireland. As an era of ‘Troubles’ could occur in Scotland, extending into England and Northern Ireland. This is due to proximity, the high number of political, communal and family links in Scotland to the RUK, and the delicate peace process within Northern Ireland which shares a similar issue. This paper will use British and Scottish Government documents prior to the Scottish referendum to argue why partition might happen and use cartography of maps of a potential partition plan for Scotland. Reports from the UK National Statistics, National Rail, and Ministry of Defence shall also be utilised, and use of journal articles that were covering the referendum.

Keywords: identity, nationalism, Scotland, unionism

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146 A Statistical Approach to Air Pollution in Mexico City and It's Impacts on Well-Being

Authors: Ana B. Carrera-Aguilar , Rodrigo T. Sepulveda-Hirose, Diego A. Bernal-Gurrusquieta, Francisco A. Ramirez Casas

Abstract:

In recent years, Mexico City has presented high levels of atmospheric pollution; the city is also an example of inequality and poverty that impact metropolitan areas around the world. This combination of social and economic exclusion, coupled with high levels of pollution evidence the loss of well-being among the population. The effect of air pollution on quality of life is an area of study that has been overlooked. The purpose of this study is to find relations between air quality and quality of life in Mexico City through statistical analysis of a regression model and principal component analysis of several atmospheric contaminants (CO, NO₂, ozone, particulate matter, SO₂) and well-being indexes (HDI, poverty, inequality, life expectancy and health care index). The data correspond to official information (INEGI, SEDEMA, and CEPAL) for 2000-2018. Preliminary results show that the Human Development Index (HDI) is affected by the impacts of pollution, and its indicators are reduced in the presence of contaminants. It is necessary to promote a strong interest in this issue in Mexico City. Otherwise, the problem will not only remain but will worsen affecting those who have less and the population well-being in a generalized way.

Keywords: air quality, Mexico City, quality of life, statistics

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145 Deproteination and Demineralization of Shrimp Waste Using Lactic Acid Bacteria for the Production of Crude Chitin and Chitosan

Authors: Farramae Francisco, Rhoda Mae Simora, Sharon Nunal

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Deproteination and demineralization efficiencies of shrimp waste using two Lactobacillus species treated with different carbohydrate sources for chitin production, its chemical conversion to chitosan and the quality of chitin and chitosan produced were determined. Using 5% glucose and 5% cassava starch as carbohydrate sources, pH slightly increased from the initial pH of 6.0 to 6.8 and 7.2, respectively after 24 h and maintained their pH at 6.7 to 7.3 throughout the treatment period. Demineralization (%) in 5 % glucose and 5 % cassava was highest during the first day of treatment which was 82% and 83%, respectively. Deproteination (%) was highest in 5% cassava starch on the 3rd day of treatment at 84.4%. The obtained chitin from 5% cassava and 5% glucose had a residual ash and protein below 1% and solubility of 59% and 44.3%, respectively. Chitosan produced from 5% cassava and 5% glucose had protein content below 0.05%; residual ash was 1.1% and 0.8%, respectively. Chitosan solubility and degree of deacetylation were 56% and 33% in 5% glucose and 48% and 29% in 5% cassava, respectively. The advantage this alternative technology offers over that of chemical extraction is large reduction in chemicals needed thus less effluent production and generation of a protein-rich liquor, although the demineralization process should be improved to achieve greater degree of deacetylation.

Keywords: alternative carbon source, bioprocessing, lactic acid bacteria, waste utilization

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144 Patient Agitation and Violence in Medical-Surgical Settings at BronxCare Hospital, Before and During COVID-19 Pandemic; A Retrospective Chart Review

Authors: Soroush Pakniyat-Jahromi, Jessica Bucciarelli, Souparno Mitra, Neda Motamedi, Ralph Amazan, Samuel Rothman, Jose Tiburcio, Douglas Reich, Vicente Liz

Abstract:

Violence is defined as an act of physical force that is intended to cause harm and may lead to physical and/or psychological damage. Violence toward healthcare workers (HCWs) is more common in psychiatric settings, emergency departments, and nursing homes; however, healthcare workers in medical setting are not spared from such events. Workplace violence has a huge burden in the healthcare industry and has a major impact on the physical and mental wellbeing of staff. The purpose of this study is to compare the prevalence of patient agitation and violence in medical-surgical settings in BronxCare Hospital (BCH) Bronx, New York, one year before and during the COVID-19 pandemic. Data collection occurred between June 2021 and August 2021, while the sampling time was from 2019 to 2021. The data were separated into two separate time categories: pre-COVID-19 (03/2019-03/2020) and COVID-19 (03/2020-03/2021). We created frequency tables for 19 variables. We used a chi-square test to determine a variable's statistical significance. We tested all variables against “restraint type”, determining if a patient was violent or became violent enough to restrain. The restraint types were “chemical”, “physical”, or both. This analysis was also used to determine if there was a statistical difference between the pre-COVID-19 and COVID-19 timeframes. Our data shows that there was an increase in incidents of violence in COVID-19 era (03/2020-03/2021), with total of 194 (62.8%) reported events, compared to pre COVID-19 era (03/2019-03/2020) with 115 (37.2%) events (p: 0.01). Our final analysis, completed using a chi-square test, determined the difference in violence in patients between pre-COVID-19 and COVID-19 era. We then tested the violence marker against restraint type. The result was statistically significant (p: 0.01). This is the first paper to systematically review the prevalence of violence in medical-surgical units in a hospital in New York, pre COVID-19 and during the COVID-19 era. Our data is in line with the global trend of increased prevalence of patient agitation and violence in medical settings during the COVID-19 pandemic. Violence and its management is a challenge in healthcare settings, and the COVID-19 pandemic has brought to bear a complexity of circumstances, which may have increased its incidence. It is important to identify and teach healthcare workers the best preventive approaches in dealing with patient agitation, to decrease the number of restraints in medical settings, and to create a less restrictive environment to deliver care.

Keywords: COVID-19 pandemic, patient agitation, restraints, violence

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143 Microstructural Characterization of Bitumen/Montmorillonite/Isocyanate Composites by Atomic Force Microscopy

Authors: Francisco J. Ortega, Claudia Roman, Moisés García-Morales, Francisco J. Navarro

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Asphaltic bitumen has been largely used in both industrial and civil engineering, mostly in pavement construction and roofing membrane manufacture. However, bitumen as such is greatly susceptible to temperature variations, and dramatically changes its in-service behavior from a viscoelastic liquid, at medium-high temperatures, to a brittle solid at low temperatures. Bitumen modification prevents these problems and imparts improved performance. Isocyanates like polymeric MDI (mixture of 4,4′-diphenylmethane di-isocyanate, 2,4’ and 2,2’ isomers, and higher homologues) have shown to remarkably enhance bitumen properties at the highest in-service temperatures expected. This comes from the reaction between the –NCO pendant groups of the oligomer and the most polar groups of asphaltenes and resins in bitumen. In addition, oxygen diffusion and/or UV radiation may provoke bitumen hardening and ageing. With the purpose of minimizing these effects, nano-layered-silicates (nanoclays) are increasingly being added to bitumen formulations. Montmorillonites, a type of naturally occurring mineral, may produce a nanometer scale dispersion which improves bitumen thermal, mechanical and barrier properties. In order to increase their lipophilicity, these nanoclays are normally treated so that organic cations substitute the inorganic cations located in their intergallery spacing. In the present work, the combined effect of polymeric MDI and the commercial montmorillonite Cloisite® 20A was evaluated. A selected bitumen with penetration within the range 160/220 was modified with 10 wt.% Cloisite® 20A and 2 wt.% polymeric MDI, and the resulting ternary composites were characterized by linear rheology, X-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The rheological tests evidenced a notable solid-like behavior at the highest temperatures studied when bitumen was just loaded with 10 wt.% Cloisite® 20A and high-shear blended for 20 minutes. However, if polymeric MDI was involved, the sequence of addition exerted a decisive control on the linear rheology of the final ternary composites. Hence, in bitumen/Cloisite® 20A/polymeric MDI formulations, the previous solid-like behavior disappeared. By contrast, an inversion in the order of addition (bitumen/polymeric MDI/ Cloisite® 20A) enhanced further the solid-like behavior imparted by the nanoclay. In order to gain a better understanding of the factors that govern the linear rheology of these ternary composites, a morphological and microstructural characterization based on XRD and AFM was conducted. XRD demonstrated the existence of clay stacks intercalated by bitumen molecules to some degree. However, the XRD technique cannot provide detailed information on the extent of nanoclay delamination, unless the entire fraction has effectively been fully delaminated (situation in which no peak is observed). Furthermore, XRD was unable to provide precise knowledge neither about the spatial distribution of the intercalated/exfoliated platelets nor about the presence of other structures at larger length scales. In contrast, AFM proved its power at providing conclusive information on the morphology of the composites at the nanometer scale and at revealing the structural modification that yielded the rheological properties observed. It was concluded that high-shear blending brought about a nanoclay-reinforced network. As for the bitumen/Cloisite® 20A/polymeric MDI formulations, the solid-like behavior was destroyed as a result of the agglomeration of the nanoclay platelets promoted by chemical reactions.

Keywords: Atomic Force Microscopy, bitumen, composite, isocyanate, montmorillonite.

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142 Synthetic Aperture Radar Remote Sensing Classification Using the Bag of Visual Words Model to Land Cover Studies

Authors: Reza Mohammadi, Mahmod R. Sahebi, Mehrnoosh Omati, Milad Vahidi

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Classification of high resolution polarimetric Synthetic Aperture Radar (PolSAR) images plays an important role in land cover and land use management. Recently, classification algorithms based on Bag of Visual Words (BOVW) model have attracted significant interest among scholars and researchers in and out of the field of remote sensing. In this paper, BOVW model with pixel based low-level features has been implemented to classify a subset of San Francisco bay PolSAR image, acquired by RADARSAR 2 in C-band. We have used segment-based decision-making strategy and compared the result with the result of traditional Support Vector Machine (SVM) classifier. 90.95% overall accuracy of the classification with the proposed algorithm has shown that the proposed algorithm is comparable with the state-of-the-art methods. In addition to increase in the classification accuracy, the proposed method has decreased undesirable speckle effect of SAR images.

Keywords: Bag of Visual Words (BOVW), classification, feature extraction, land cover management, Polarimetric Synthetic Aperture Radar (PolSAR)

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141 Psychological Capital and Work Engagement as Predictors of Employee Performance in a Technology Industry During COVID-19 Pandemic: Basis for Performance Management

Authors: Marion Francisco

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The study sought to investigate the psychological capital and work engagement of employees as predictors of employee performance in the technology industry in Makati City. It made used of a descriptive correlational method of research and utilized standardized tests, such as Psychological Capital Scale, Utrech Work Engagement Scale, and Employee Performance Scale. A convenience sampling technique was used to gather data samples from 100 populations with the help of Roscoe concept approach. The study revealed that both psychological capital and work engagement have a significant relationship with employee performance. Psychological capital and work engagement can predict employee performance of the respondents. With the results given, the study suggests: (1) to focus on maintaining a high level of psychological capital and work engagement, on achieving a very high level of psychological capital and work engagement, and on improving the low level of psychological capital or work engagement mostly during this COVID-19 pandemic using the proposed employee performance management plan and (2) to create a proposed employee performance management plan as necessary to tailor fit on employees needs to enhance their performance that will help meet company and client’s needs.

Keywords: employee performance, performance management, psychological capital, technology industry, work engagement

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140 Study Case of Spacecraft Instruments in Structural Modelling with Nastran-Patran

Authors: Francisco Borja de Lara, Ali Ravanbakhsh, Robert F. Wimmer-Schweingruber, Lars Seimetz, Fermín Navarro

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The intense structural loads during the launch of a spacecraft represent a challenge for the space structure designers because enough resistance has to be achieved while maintaining at the same time the mass and volume within the allowable margins of the mission requirements and inside the limits of the budget project. In this conference, we present the structural analysis of the Lunar Lander Neutron Dosimetry (LND) experiment on the Chang'E4 mission, the first probe to land on the moon’s far side included in the Chinese’ Moon Exploration Program by the Chinese National Space Administration. To this target, the software Nastran/Patran has been used: a structural model in Patran and a structural analysis through Nastran have been realized. Next, the results obtained are used both for the optimization process of the spacecraft structure, and as input parameters for the model structural test campaign. In this way, the feasibility of the lunar instrument structure is demonstrated in terms of the modal modes, stresses, and random vibration and a better understanding of the structural tests design is provided by our results.

Keywords: Chang’E4, Chinese national space administration, lunar lander neutron dosimetry, nastran-patran, structural analysis

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139 Optimizing Resource Allocation and Indoor Location Using Bluetooth Low Energy

Authors: Néstor Álvarez-Díaz, Pino Caballero-Gil, Héctor Reboso-Morales, Francisco Martín-Fernández

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The recent tendency of "Internet of Things" (IoT) has developed in the last years, causing the emergence of innovative communication methods among multiple devices. The appearance of Bluetooth Low Energy (BLE) has allowed a push to IoT in relation to smartphones. In this moment, a set of new applications related to several topics like entertainment and advertisement has begun to be developed but not much has been done till now to take advantage of the potential that these technologies can offer on many business areas and in everyday tasks. In the present work, the application of BLE technology and smartphones is proposed on some business areas related to the optimization of resource allocation in huge facilities like airports. An indoor location system has been developed through triangulation methods with the use of BLE beacons. The described system can be used to locate all employees inside the building in such a way that any task can be automatically assigned to a group of employees. It should be noted that this system cannot only be used to link needs with employees according to distances, but it also takes into account other factors like occupation level or category. In addition, it has been endowed with a security system to manage business and personnel sensitive data. The efficiency of communications is another essential characteristic that has been taken into account in this work.

Keywords: bluetooth low energy, indoor location, resource assignment, smartphones

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138 Cassava Plant Architecture: Insights from Genome-Wide Association Studies

Authors: Abiodun Olayinka, Daniel Dzidzienyo, Pangirayi Tongoona, Samuel Offei, Edwige Gaby Nkouaya Mbanjo, Chiedozie Egesi, Ismail Yusuf Rabbi

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Cassava (Manihot esculenta Crantz) is a major source of starch for various industrial applications. However, the traditional cultivation and harvesting methods of cassava are labour-intensive and inefficient, limiting the supply of fresh cassava roots for industrial starch production. To achieve improved productivity and quality of fresh cassava roots through mechanized cultivation, cassava cultivars with compact plant architecture and moderate plant height are needed. Plant architecture-related traits, such as plant height, harvest index, stem diameter, branching angle, and lodging tolerance, are critical for crop productivity and suitability for mechanized cultivation. However, the genetics of cassava plant architecture remain poorly understood. This study aimed to identify the genetic bases of the relationships between plant architecture traits and productivity-related traits, particularly starch content. A panel of 453 clones developed at the International Institute of Tropical Agriculture, Nigeria, was genotyped and phenotyped for 18 plant architecture and productivity-related traits at four locations in Nigeria. A genome-wide association study (GWAS) was conducted using the phenotypic data from a panel of 453 clones and 61,238 high-quality Diversity Arrays Technology sequencing (DArTseq) derived Single Nucleotide Polymorphism (SNP) markers that are evenly distributed across the cassava genome. Five significant associations between ten SNPs and three plant architecture component traits were identified through GWAS. We found five SNPs on chromosomes 6 and 16 that were significantly associated with shoot weight, harvest index, and total yield through genome-wide association mapping. We also discovered an essential candidate gene that is co-located with peak SNPs linked to these traits in M. esculenta. A review of the cassava reference genome v7.1 revealed that the SNP on chromosome 6 is in proximity to Manes.06G101600.1, a gene that regulates endodermal differentiation and root development in plants. The findings of this study provide insights into the genetic basis of plant architecture and yield in cassava. Cassava breeders could leverage this knowledge to optimize plant architecture and yield in cassava through marker-assisted selection and targeted manipulation of the candidate gene.

Keywords: Manihot esculenta Crantz, plant architecture, DArtseq, SNP markers, genome-wide association study

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137 Medication Side Effects: Implications on the Mental Health and Adherence Behaviour of Patients with Hypertension

Authors: Irene Kretchy, Frances Owusu-Daaku, Samuel Danquah

Abstract:

Hypertension is the leading risk factor for cardiovascular diseases, and a major cause of death and disability worldwide. This study examined whether psychosocial variables influenced patients’ perception and experience of side effects of their medicines, how they coped with these experiences and the impact on mental health and medication adherence to conventional hypertension therapies. Methods: A hospital-based mixed methods study, using quantitative and qualitative approaches was conducted on hypertensive patients. Participants were asked about side effects, medication adherence, common psychological symptoms, and coping mechanisms with the aid of standard questionnaires. Information from the quantitative phase was analyzed with the Statistical Package for Social Sciences (SPSS) version 20. The interviews from the qualitative study were audio-taped with a digital audio recorder, manually transcribed and analyzed using thematic content analysis. The themes originated from participant interviews a posteriori. Results: The experiences of side effects – such as palpitations, frequent urination, recurrent bouts of hunger, erectile dysfunction, dizziness, cough, physical exhaustion - were categorized as no/low (39.75%), moderate (53.0%) and high (7.25%). Significant relationships between depression (x 2 = 24.21, P < 0.0001), anxiety (x 2 = 42.33, P < 0.0001), stress (x 2 = 39.73, P < 0.0001) and side effects were observed. A logistic regression model using the adjusted results for this association are reported – depression [OR = 1.9 (1.03 – 3.57), p = 0.04], anxiety [OR = 1.5 (1.22 – 1.77), p = < 0.001], and stress [OR = 1.3 (1.02 – 1.71), p = 0.04]. Side effects significantly increased the probability of individuals to be non-adherent [OR = 4.84 (95% CI 1.07 – 1.85), p = 0.04] with social factors, media influences and attitudes of primary caregivers further explaining this relationship. The personal adoption of medication modifying strategies, espousing the use of complementary and alternative treatments, and interventions made by clinicians were the main forms of coping with side effects. Conclusions: Results from this study show that contrary to a biomedical approach, the experience of side effects has biological, social and psychological interrelations. The result offers more support for the need for a multi-disciplinary approach to healthcare where all forms of expertise are incorporated into health provision and patient care. Additionally, medication side effects should be considered as a possible cause of non-adherence among hypertensive patients, thus addressing this problem from a Biopsychosocial perspective in any intervention may improve adherence and invariably control blood pressure.

Keywords: biopsychosocial, hypertension, medication adherence, psychological disorders

Procedia PDF Downloads 343
136 Development of Biotechnological Emulsion Based on Bullfrog (Rana catesbeiana Shaw) Oil: A Preliminary Study

Authors: Lourena M. Veríssimo, Lucas A. Machado, Renata Rutckeviski, Francisco H. Xavier Júnior, Éverton N. Alencar, Andreza R. V. Morais, Teresa R. F. Dantas, Christian M. Oliveira, Arnóbio A. Silva Júnior, Eryvaldo S. T. Egito

Abstract:

This study aimed to obtain emulsion systems based on bullfrog oil (BO). The BO was extracted at 80ºC and analyzed by Gas Chromatography-Mass Spectrometry (GC/MS). The critical Hydrophilic-Lipophilic Balance (HLBc) Assay of the BO was performed through BO, Tween® 20, Span® 80 and deionized water mixtures using an Ultra-Turrax® and determined using dynamic light scattering, pH, electrical conductivity and creaming rate. Then, a pseudoternary phase diagram (PPD) was constructed by water titration. The GC/MS analysis of BO suggested Methyl Oleate (9.26%) as major compound. The HLBc was 12.1, wherein the correspondent emulsion showed a pH of 4.83±1.29, electrical conductivity of 103.65 µS, creaming rate of 2.51±0.54%, droplet size of 207.07±8.31 nm and polydispersity index of 0.212±0.005. The PPD showed different formulations characterized as O/W emulsions. Thus, the PPD proved to be a useful tool to produce BO emulsions, in which their constituents may vary within the range of the desired system.

Keywords: bullfrog (Rana catesbeiana Shaw) oil, emulsion production, hydrophilic-lipophilic balance, gas chromatography/mass spectrometry analysis

Procedia PDF Downloads 483
135 Environmental Contamination of Water Bodies by Waste Produced by Slaughterhouses and the Prevalence of Waterborne Diseases in Kumba Municipality

Authors: Maturin Désiré Sop Sop, Didien Njumba Besende, Samuel Fosso Wamba

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This study seeks to examine the nexus between drinking water sources in the Kumba municipality and its related health implications vis-à-vis the recurrent incidences of waterborne diseases such as Typhoid, Cholera, Diarrhea, Dysentery, Hepatitis A and malaria. The study adopted a purposive sampling technique in which surveys were conducted between the months of June to December 2022. 150 questionnaires were retrieved from the 210 administered to the affected population of Kosala, Buea Road and Mambanda. Information for the study was collected using surveys, questionnaires, key informant interviews, the laboratory analysis of collected drinking water samples, the researcher’s direct observation as well and hospital reports on the prevalence of waterborne diseases. Water samples from the nearby streams and wells, which were communally used by the local population for drinking, and five slaughterhouses within the affected areas were laboratory tested to determine alterations in their chemical, physical and microbiological characteristics. The collected water samples from all the streams and wells used for drinking were tested for changes in properties such as temperature, turbidity, EC, pH, TDS, TSS, Cl, SO42-, PO43-, NO3-, Fe, Na, BOD, COD, DO, E.coli and total coliform concentration. These results were then compared with the WHO regulations for water quality. The results from the laboratory analysis of drinking water sources, which were at the same time used by the surrounding abattoirs revealed significant alterations in the water quality parameters such as temperature, turbidity, EC, pH, TDS, TSS, Cl, SO42-, PO43-, NO3-, Fe, Na, BOD, COD, DO, E.coli and total coliform concentration. This is due to the channeling of untreated wastes into the different drinking water points as well as the inter-use of dirty utensils such as buckets from slaughterhouses to fetch water from the streams and wells that serve as drinking water sources for the local population. On the human health aspect, the results were later compared with hospital data, and they revealed that the consumption of such contaminated water in the localities of Kosala, Mambanda, and Buea road negatively affected the local population because of the high incidences of Typhoid Cholera, Diarrhea, Dysentery, Hepatitis A and malaria. The poor management of drinking water sources pollutes streams and significantly exposes the local population to lots of waterborne diseases. Efforts should be made to provide clean pipe-borne water to the affected localities of Kumba as well as to ensure the proper management of wastes.

Keywords: drinking water, diseases, Kumba, municipality

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134 Xenografts: Successful Penetrating Keratoplasty Between Two Species

Authors: Francisco Alvarado, Luz Ramírez

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Corneal diseases are one of the main causes of visual impairment and affect almost 4 million, and this study assesses the effects of deep anterior lamellar keratoplasty (DALK) with porcine corneal stroma and postoperative topical treatment with tacrolimus in patients with infectious keratitis. No patient was observed with clinical graft rejection. Among the cases: 2 were positive to fungal culture, 2 with Aspergillus and the other 8 cases were confirmed by bacteriological culture. Corneal diseases are one of the main causes of visual impairment and affect almost 4 million. This study assesses the effects of deep anterior lamellar keratoplasty (DALK) with porcine corneal stroma and postoperative topical treatment with tacrolimus in patients with infectious keratitis. Receiver bed diameters ranged from 7.00 to 9.00 mm. No incidents of Descemet's membrane perforation were observed during surgery. During the follow-up period, no corneal graft splitting, IOP increase, or intolerance to tacrolimus were observed. Deep anterior lamellar keratoplasty seems to be the best option to avoid xenograft rejection, and it could help new surgical techniques in humans.

Keywords: ophthalmology, cornea, corneal transplant, xenografts, surgical innovations

Procedia PDF Downloads 57
133 Rural Tourism as a Development Strategy in Communities of the Sierra Gorda of Querétaro

Authors: Eduardo Ruiz-Corzo, Luis Rodrigo Valencia Perez, Jorge Francisco Barragan Lopez

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The article shows the pressing conditions of marginalization prevailing in the Sierra Gorda, in the northern state of Queretaro, so it is essential to identify business options that generate a complementary source of income in a sustainable manner, in accordance with the fact that the area is a Biosphere Reserve by UNESCO. In this sense, the study identifies the enormous scenic richness of the area, the growing demand for leisure activities of the urban centers and the multifunctionality that adds, in a complementary way, the traditional activities that up to now have achieved the quality of life levels. From the application of the 43 interviews and 183 surveys, confirms the fact that the post-visit perception exceeds the expectations of the visitors emerges and affirms that the image that has been projected is attractive and timely. In order to understand how the current model of tourism promoted in the region is working, there is a need to evaluate it in a theoretical-methodological framework considering sustainable development assumptions. In order to determine the degree of contribution to business development, strengthening of social capital, and enjoyment and appreciation of cultural and natural heritage in the region.

Keywords: marginalization, rural tourism, multifunctionality, sustainability, revenue

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132 Estimating PM2.5 Concentrations Based on Landsat 8 Imagery and Historical Field Data over the Metropolitan Area of Mexico City

Authors: Rodrigo T. Sepulveda-Hirose, Ana B. Carrera-Aguilar, Francisco Andree Ramirez-Casas, Alondra Orozco-Gomez, Miguel Angel Sanchez-Caro, Carlos Herrera-Ventosa

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High concentrations of particulate matter in the atmosphere pose a threat to human health, especially over areas with high concentrations of population; however, field air pollution monitoring is expensive and time-consuming. In order to achieve reduced costs and global coverage of the whole urban area, remote sensing can be used. This study evaluates PM2.5 concentrations, over the Mexico City´s metropolitan area, are estimated using atmospheric reflectance from LANDSAT 8, satellite imagery and historical PM2.5 measurements of the Automatic Environmental Monitoring Network of Mexico City (RAMA). Through the processing of the available satellite images, a preliminary model was generated to evaluate the optimal bands for the generation of the final model for Mexico City. Work on the final model continues with the results of the preliminary model. It was found that infrared bands have helped to model in other cities, but the effectiveness that these bands could provide for the geographic and climatic conditions of Mexico City is still being evaluated.

Keywords: air pollution modeling, Landsat 8, PM2.5, remote sensing

Procedia PDF Downloads 157
131 Identification of Candidate Gene for Root Development and Its Association With Plant Architecture and Yield in Cassava

Authors: Abiodun Olayinka, Daniel Dzidzienyo, Pangirayi Tongoona, Samuel Offei, Edwige Gaby Nkouaya Mbanjo, Chiedozie Egesi, Ismail Yusuf Rabbi

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Cassava (Manihot esculenta Crantz) is a major source of starch for various industrial applications. However, the traditional cultivation and harvesting methods of cassava are labour-intensive and inefficient, limiting the supply of fresh cassava roots for industrial starch production. To achieve improved productivity and quality of fresh cassava roots through mechanized cultivation, cassava cultivars with compact plant architecture and moderate plant height are needed. Plant architecture-related traits, such as plant height, harvest index, stem diameter, branching angle, and lodging tolerance, are critical for crop productivity and suitability for mechanized cultivation. However, the genetics of cassava plant architecture remain poorly understood. This study aimed to identify the genetic bases of the relationships between plant architecture traits and productivity-related traits, particularly starch content. A panel of 453 clones developed at the International Institute of Tropical Agriculture, Nigeria, was genotyped and phenotyped for 18 plant architecture and productivity-related traits at four locations in Nigeria. A genome-wide association study (GWAS) was conducted using the phenotypic data from a panel of 453 clones and 61,238 high-quality Diversity Arrays Technology sequencing (DArTseq) derived Single Nucleotide Polymorphism (SNP) markers that are evenly distributed across the cassava genome. Five significant associations between ten SNPs and three plant architecture component traits were identified through GWAS. We found five SNPs on chromosomes 6 and 16 that were significantly associated with shoot weight, harvest index, and total yield through genome-wide association mapping. We also discovered an essential candidate gene that is co-located with peak SNPs linked to these traits in M. esculenta. A review of the cassava reference genome v7.1 revealed that the SNP on chromosome 6 is in proximity to Manes.06G101600.1, a gene that regulates endodermal differentiation and root development in plants. The findings of this study provide insights into the genetic basis of plant architecture and yield in cassava. Cassava breeders could leverage this knowledge to optimize plant architecture and yield in cassava through marker-assisted selection and targeted manipulation of the candidate gene.

Keywords: manihot esculenta crantz, plant architecture, dartseq, snp markers, genome-wide association study

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130 Development of an Appropriate Method for the Determination of Multiple Mycotoxins in Pork Processing Products by UHPLC-TCFLD

Authors: Jason Gica, Yi-Hsieng Samuel Wu, Deng-Jye Yang, Yi-Chen Chen

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Mycotoxins, harmful secondary metabolites produced by certain fungi species, pose significant risks to animals and humans worldwide. Their stable properties lead to contamination during grain harvesting, transportation, and storage, as well as in processed food products. The prevalence of mycotoxin contamination has attracted significant attention due to its adverse impact on food safety and global trade. The secondary contamination pathway from animal products has been identified as an important route of exposure, posing health risks for livestock and humans consuming contaminated products. Pork, one of the highly consumed meat products in Taiwan according to the National Food Consumption Database, plays a critical role in the nation's diet and economy. Given its substantial consumption, pork processing products are a significant component of the food supply chain and a potential source of mycotoxin contamination. This study is paramount for formulating effective regulations and strategies to mitigate mycotoxin-related risks in the food supply chain. By establishing a reliable analytical method, this research contributes to safeguarding public health and enhancing the quality of pork processing products. The findings will serve as valuable guidance for policymakers, food industries, and consumers to ensure a safer food supply chain in the face of emerging mycotoxin challenges. An innovative and efficient analytical approach is proposed using Ultra-High Performance Liquid Chromatography coupled with Temperature Control Fluorescence Detector Light (UHPLC-TCFLD) to determine multiple mycotoxins in pork meat samples due to its exceptional capacity to detect multiple mycotoxins at the lowest levels of concentration, making it highly sensitive and reliable for comprehensive mycotoxin analysis. Additionally, its ability to simultaneously detect multiple mycotoxins in a single run significantly reduces the time and resources required for analysis, making it a cost-effective solution for monitoring mycotoxin contamination in pork processing products. The research aims to optimize the efficient mycotoxin QuEChERs extraction method and rigorously validate its accuracy and precision. The results will provide crucial insights into mycotoxin levels in pork processing products.

Keywords: multiple-mycotoxin analysis, pork processing products, QuEChERs, UHPLC-TCFLD, validation

Procedia PDF Downloads 30
129 Multi-Criteria Inventory Classification Process Based on Logical Analysis of Data

Authors: Diana López-Soto, Soumaya Yacout, Francisco Ángel-Bello

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Although inventories are considered as stocks of money sitting on shelve, they are needed in order to secure a constant and continuous production. Therefore, companies need to have control over the amount of inventory in order to find the balance between excessive and shortage of inventory. The classification of items according to certain criteria such as the price, the usage rate and the lead time before arrival allows any company to concentrate its investment in inventory according to certain ranking or priority of items. This makes the decision making process for inventory management easier and more justifiable. The purpose of this paper is to present a new approach for the classification of new items based on the already existing criteria. This approach is called the Logical Analysis of Data (LAD). It is used in this paper to assist the process of ABC items classification based on multiple criteria. LAD is a data mining technique based on Boolean theory that is used for pattern recognition. This technique has been tested in medicine, industry, credit risk analysis, and engineering with remarkable results. An application on ABC inventory classification is presented for the first time, and the results are compared with those obtained when using the well-known AHP technique and the ANN technique. The results show that LAD presented very good classification accuracy.

Keywords: ABC multi-criteria inventory classification, inventory management, multi-class LAD model, multi-criteria classification

Procedia PDF Downloads 845
128 Simultaneous Removal of Arsenic and Toxic Metals from Contaminated Soil: a Pilot-Scale Demonstration

Authors: Juan Francisco Morales Arteaga, Simon Gluhar, Anela Kaurin, Domen Lestan

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Contaminated soils are recognized as one of the most pressing global environmental problems. As is one of the most hazardous elements: chronic exposure to arsenic has devastating effects on health, cardiovascular diseases, cancer, and eventually death. Pb, Zn and Cd are very highly toxic metals that affect almost every organ in the body. With this in mind, new technologies for soil remediation processes are urgently needed. Calcareous artificially contaminated soil containing 231 mg kg-1 As and historically contaminated with Pb, Zn and Cd was washed with a 1:1.5 solid-liquid ratio of 90 mM EDTA, 100 mM oxalic acid, and 50 mM sodium dithionite to remove 59, 75, 29, and 53% of As, Pb, Zn, and Cd, respectively. To reduce emissions of residual EDTA and chelated metals from the remediated soil, zero valent iron (ZVI) was added (1% w/w) to the slurry of the washed soil immediately prior to rinsing. Experimental controls were conducted without the addition of ZVI after remediation. The use of ZVI reduced metal leachability and minimized toxic emissions 21 days after remediation. After this time, NH4NO3 extraction was performed to determine the mobility of toxic elements in the soil. In addition, Unified Human BioaccessibilityMethod (UBM) was performed to quantify the bioaccessibility levels of metals in stimulated human gastric and gastrointestinal phases.

Keywords: soil remediation, soil science, soil washing, toxic metals removal

Procedia PDF Downloads 150
127 Induced Thermo-Osmotic Convection for Heat and Mass Transfer

Authors: Francisco J. Arias

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Consideration is given to a mechanism of heat and mass transport in solutions similar than that of natural convection but with one important difference. Here the mechanism is not promoted by density differences in the fluid occurring due to temperature gradients (coefficient of thermal expansion) but rather by solubility differences due to the thermal dependence of the solubility (coefficient of thermal solubility). Utilizing a simplified physical model, it is shown that by the proper choice of the concentration of a given solution, convection might be induced by the alternating precipitation of the solute -when the solution becomes supersaturated, and its posterior recombination when changes in temperature occurs. The spontaneous change in the Gibbs free energy during the mixing is the driven force for the mechanism. The maximum extractable energy from this new type of thermal convection was derived. Experimental data from a closed-loop circuit was obtained demonstrating the feasibility for continuous separation and recombination of the solution. This type of heat and mass transport -which doesn’t depend on gravity, might potentially be interesting for heat and mass transport downwards (as in solar-roof collectors to inside homes), horizontal (e.g., microelectronic applications), and in microgravity (space technology). Also, because the coefficient of thermal solubility could be positive or negative, the investigated thermo-osmosis convection can be used either for heating or cooling.

Keywords: natural convection, thermal gradient, solubility, osmotic pressure

Procedia PDF Downloads 266
126 The Other Dreamers: A Study of the Relationship between Returned Migration and Entrepreneurship

Authors: Pascual García, Francisco Ochoa, Jessica Ordoñez

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The links between migration and development have been widely written and analyzed from different perspectives. However, the nexus between entrepreneurship and migration is of recent interest. The different studies related to this have focused on the ventures of ethnic enclaves, or on transnational businesses, which link the community of origin and destination. Beyond this perspective, this work analyzes the return migration, (a few studies until now, but forming part of a theoretical body of migration). As a result of the European crisis started between 2007-2008. Many Ecuadorians who lived in Europe, decided to return to their place of origin. The rise of the price of the oil and commodities presented a better panorama in Ecuador than in Europe. Faced with the magnitude of returnees, the opportunities for entrepreneurship in Ecuador increased (Accumulation of human capital, social capital, learned skills and capital). Thus there is an interest in the possibility of returned migrants in the country to start a business in their place of origin. The following study is the result of this. A survey of 110 returned migrants was carried out in the south of Ecuador and, using a Probit econometric model, we determined that the variables specified as geographic area, sex, education level are not significant, so they are not determinant when undertaking. However, time abroad and skills learned, if they were significant at the time of the decision to start a business.

Keywords: entrepreneurship, development, migration, returned migration

Procedia PDF Downloads 178