Search results for: Kevin Cano Pulido
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 190

Search results for: Kevin Cano Pulido

130 An Investigation of Tourists’ Destination Loyalty: A Case Study of Bangkok, Thailand

Authors: Sukritta Larsen, Kevin Wongleedee

Abstract:

The purposes of this research were to study tourists’ destination loyalty from the perspective of international tourists in Bangkok and to study the level of interest to revisit Bangkok in the near future. A probability random sampling of 200 international tourists was utilized. Half of the sample group was male and the other half was female. A Likert-five-scale questionnaire was designed to collect the data and small in-depth interviews were also used to obtain their opinions. The findings revealed that the majority of respondents had a medium level of loyalty. When examined in detail, the destination loyalty indicators can be ranked according to the mean average from high to low as follows: to recommend the visit, to say positive things, to revisit in the next three years, to refer the information, and to plan to visit regularly. Finally, the findings from the in-depth interviews with small group of international tourists revealed that the major obstacles that prevented many international tourists who may interested in revisiting Thailand included traffic congestions, high crime rate, and political instability.

Keywords: destination loyalty, international tourists, revisit, Bangkok

Procedia PDF Downloads 315
129 Improved Small-Signal Characteristics of Infrared 850 nm Top-Emitting Vertical-Cavity Lasers

Authors: Ahmad Al-Omari, Osama Khreis, Ahmad M. K. Dagamseh, Abdullah Ababneh, Kevin Lear

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High-speed infrared vertical-cavity surface-emitting laser diodes (VCSELs) with Cu-plated heat sinks were fabricated and tested. VCSELs with 10 mm aperture diameter and 4 mm of electroplated copper demonstrated a -3dB modulation bandwidth (f-3dB) of 14 GHz and a resonance frequency (fR) of 9.5 GHz at a bias current density (Jbias) of only 4.3 kA/cm2, which corresponds to an improved f-3dB2/Jbias ratio of 44 GHz2/kA/cm2. At higher and lower bias current densities, the f-3dB2/ Jbias ratio decreased to about 30 GHz2/kA/cm2 and 18 GHz2/kA/cm2, respectively. Examination of the analogue modulation response demonstrated that the presented VCSELs displayed a steady f-3dB/ fR ratio of 1.41±10% over the whole range of the bias current (1.3Ith to 6.2Ith). The devices also demonstrated a maximum modulation bandwidth (f-3dB max) of more than 16 GHz at a bias current less than the industrial bias current standard for reliability by 25%.

Keywords: current density, high-speed VCSELs, modulation bandwidth, small-signal characteristics, thermal impedance, vertical-cavity surface-emitting lasers

Procedia PDF Downloads 530
128 Synthesis and Characterization of Biodegradable Elastomeric Polyester Amide for Tissue Engineering Applications

Authors: Abdulrahman T. Essa, Ahmed Aied, Omar Hamid, Felicity R. A. J. Rose, Kevin M. Shakesheff

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Biodegradable poly(ester amide)s are promising polymers for biomedical applications such as drug delivery and tissue engineering because of their optimized chemical and physical properties. In this study, we developed a biodegradable polyester amide elastomer poly(serinol sebacate) (PSS) composed of crosslinked networks based on serinol and sebacic acid. The synthesized polymers were characterized to evaluate their chemical structures, mechanical properties, degradation behaviors and in vitro cytocompatibility. Analysis of proton nuclear magnetic resonance and Fourier transform infrared spectroscopy revealed the structure of the polymer. The PSS exhibit excellent solubility in a variety of solvents such as methanol, dimethyl sulfoxide and dimethylformamide. More importantly, the mechanical properties of PSS could be tuned by changing the curing conditions. In addition, the 3T3 fibroblast cells cultured on the PSS demonstrated good cell attachment and high viability.

Keywords: biodegradable, biomaterial, elastomer, mechanical properties, poly(serinol sebacate)

Procedia PDF Downloads 314
127 Stun Practices in Swine in the Valle De Aburrá and Animal Welfare

Authors: Natalia Uribe Corrales, Carolina Cano Arroyave, Santiago Henao Villegas

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Introduction: Stunning is an important stage in the meat industry due to the repercussions on the characteristics of the carcass. It has been demonstrated that inadequate stun can lead to hematomas, fractures and promote the appearance of pale, soft and exudative meat due to the stress caused in animals. In Colombia, gas narcosis and electrical stunning are the two authorized methods in pigs. Objective: To describe the practices of stunning in the Valle de Aburrá and its relation with animal welfare. Methods: A descriptive cross - sectional study was carried out in Valle de Aburrá slaughterhouses, which were authorized by National Institute for Food and Medicine Surveillance (INVIMA). Variables such as stunning method, presence of vocalization, falls, slips, rhythmic breathing, corneal reflex and attempts to incorporate after stunning, stun time and time between stun and bleeding were analyzed. Results: 225 pigs were analyzed, finding that 50.2% had electrical stun, whose amperage and voltage were 1.23 (A) and 120 (V) respectively; 49.8% of the animals were stunned with CO2 chamber whose concentration was always above 95%, the mean desensitization time was 16.8 seconds (d.e.5.37); the mean time of stunning - bleeding was 47.9 seconds (d.e.13.9); similarly, it was found that 27.1% had vocalizations after stunning; 12% had falls; 10.7% showed rhythmic breathing; 33.3% exhibited corneal reflex; and 10.7% had reincorporation attempts. Conclusions: The methods of stunning used in the Valle de Aburrá, although performed with those permitted by law, are shortcomings in relation to the amperage and voltage used for each type of pig, as well, it is found that welfare animal is being violated to find signology of an inadequate desensitization. It is necessary to promote compliance with the principles of stunning according to Animal Welfare, and keep in mind that in electrical desensitization, the calibration of the equipment must be guaranteed (pressure according to the type of animal or current applied and the position where the electrodes are) and in the narcosis the equipment should be calibrated to ensure proper gas concentration and exposure time.

Keywords: animal welfare, pigs, quality of meat, stun methods

Procedia PDF Downloads 194
126 Weathering of a Calcarenite Stone in the Archaeological Site of Volubilis – Morocco

Authors: Issam Aalil, Kevin Beck, Khalid Cherkaoui, Xavier Brunetaud, Ali Chaaba, Muzahim Al-Mukhtar

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Volubilis is the most important archaeological site in Morocco. It was founded in the 3rd century B.C about thirty kilometres north of Meknes and has been registered on the UNESCO World Heritage list since 1997. The site is located in a region where reigns the semi-arid continental climate, characterized by strong thermal amplitudes. A beige-yellowish calcarenite limestone is the most largely used on Volubilis site, representing about 60% of the total volume of building stones. This limestone is mainly affected by scaling and sanding according to field observations. In order to preserve monuments of this site, characterization of calcarenite weathering is essential. This work aims at investigating the nature of the dominant weathering. For this goal, mineralogical compositions of deteriorated and fresh samples are compared. Besides, the risk of damage by thermal stresses is estimated. The results of this study show that there is no major difference observed between the mineralogy of the fresh and weathered calcarenite samples. Otherwise, thermal stresses may have an important role in the weathering of calcarenite limestone by fatigue.

Keywords: characterisation, stone, thermal stresses, Volubilis, weathering

Procedia PDF Downloads 319
125 WHO Surgical Safety Checklist in a Rural Ugandan Hospital, Barriers and Drivers to Implementation

Authors: Lucie Litvack, Malaz Elsaddig, Kevin Jones

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There is strong evidence to support the efficacy of the World Health Organization (WHO) Surgical Safety Checklist in improving patient safety; however, its use can be associated with difficulties. This study uses qualitative data collected in Kitovu Healthcare Complex, a rural Ugandan hospital, to identify factors that may influence the use of the checklist in a low-income setting. Potential barriers to and motivators for the hospital’s use of this checklist are identified and explored through observations of current patient safety practices; semi-structured interviews with theatre staff; a focus group with doctors; and trial implementation of the checklist. Barriers identified include the institutional context; knowledge and understanding; patient safety culture; resources and checklist contents. Motivators for correct use include prior knowledge; team attitudes; and a hospital advocate. Challenges are complex and unique to this socioeconomic context. Stepwise change to improve patient safety practices, local champions, whole team training, and checklist modification may assist the implementation and sustainable use of the checklist in an effective way.

Keywords: anaesthesia, patient safety, Uganda, WHO surgical safety checklist

Procedia PDF Downloads 329
124 Hong Kong Chinese-Speaking Adolescents Diagnosed with Dyslexia: What Is and Is Not Improved?

Authors: Kevin Kien Hoa Chung

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The present study was to investigate cognitive-linguistic skills that might distinguish the improved dyslexics from the non-improved dyslexics. Twenty-eight improved dyslexics and 28 non-improved dyslexics were selected from a pool of 254 students diagnosed as dyslexics in Grade 1 to 2. These students were administered measures: morphological skills, visual-orthographic skills, rapid naming skills, working memory, reading comprehension, writing, word reading, word dictation, and one-minute word reading. Findings showed that the improved dyslexics performed better than the non-improved dyslexics in visual-orthographic skills, word reading, one-minute reading, writing, and reading comprehension. Furthermore, the improved dyslexics showed fewer cognitive-linguistic deficits compared with the non-improved dyslexics. Among the 4 cognitive-linguistic measures, morphological skills and visual-orthographic skills showed the greatest power in discriminating the improved and non-improved dyslexics. Results underscore the importance of cognitive-linguistic skills underlying the manifestations of the improved and non-improved dyslexia in Chinese adolescents.

Keywords: adolescents, chinese language, improved dyslexics, non-improved dyslexics

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123 Dietary Gluten and the Balance of Gut Microbiota in the Dextran Sulphate Sodium Induced Colitis Model

Authors: Austin Belfiori, Kevin Rinek, Zach Barcroft, Jennifer Berglind

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Diet influences the composition of the gut microbiota and host's health. Disruption of the balance among the microbiota, epithelial cells, and resident immune cells in the intestine is involved in the pathogenesis of inflammatory bowel disease (IBD). To study the role of gut microbiota in intestinal inflammation, the microbiome of control mice (C57BL6) given a gluten-containing standard diet versus C57BL6 mice given the gluten-free (GF) feed (n=10 in each group) was examined. All mice received the 3% DSS for 5 days. Throughout the study, feces were collected and processed for DNA extraction and MiSeq Illumina sequencing of V4 region of bacterial 16S rRNA gene. Alpha and beta diversities and compositional differences at phylum and genus levels were determined in intestinal microbiota. The mice receiving the GF diet showed a significantly increased abundance of Firmicutes and a decrease of Bacteroides and Lactobacillus at phylum level. Therefore, the gluten free diet led to reductions in beneficial gut bacteria populations. These findings indicate a role of wheat gluten in dysbiosis of the intestinal microbiota.

Keywords: gluten, colitis, microbiota, DSS, dextran sulphate sodium

Procedia PDF Downloads 178
122 Hate Speech in Selected Nigerian Newspapers

Authors: Laurel Chikwado Madumere, Kevin O. Ugorji

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A speech is said to be full of hate when it appropriates disparaging and vituperative locutions and/or appellations, which are riddled with prejudices and misconceptions about an antagonizing party on the grounds of gender, race, political orientation, religious affiliations, tribe, etc. Due largely to the dichotomies and polarities that exist in Nigeria across political ideological spectrum, tribal affiliations, and gender contradistinctions, there are possibilities for the existence of socioeconomic, religious and political conditions that would induce, provoke and catalyze hate speeches in Nigeria’s mainstream media. Therefore the aim of this paper is to investigate, using select daily newspapers in Nigeria, the extent and complexity of those likely hate speeches that emanate from the pluralism in Nigeria and to set in to relief, the discrepancies and contrariety in the interpretation of those hate words. To achieve the above, the paper shall be qualitative in orientation as it shall be using the Speech Act Theory of J. L. Austin and J. R. Searle to interpret and evaluate the hate speeches in the select Nigerian daily newspapers. Also this paper shall help to elucidate the conditions that generate hate, and inform the government and NGOs how best to approach those conditions and put an end to the possible violence and extremism that emanate from extreme cases of hate.

Keywords: extremism, gender, hate speech, pluralism, prejudice, speech act theory

Procedia PDF Downloads 118
121 Malignancy Assessment of Brain Tumors Using Convolutional Neural Network

Authors: Chung-Ming Lo, Kevin Li-Chun Hsieh

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The central nervous system in the World Health Organization defines grade 2, 3, 4 gliomas according to the aggressiveness. For brain tumors, using image examination would have a lower risk than biopsy. Besides, it is a challenge to extract relevant tissues from biopsy operation. Observing the whole tumor structure and composition can provide a more objective assessment. This study further proposed a computer-aided diagnosis (CAD) system based on a convolutional neural network to quantitatively evaluate a tumor's malignancy from brain magnetic resonance imaging. A total of 30 grade 2, 43 grade 3, and 57 grade 4 gliomas were collected in the experiment. Transferred parameters from AlexNet were fine-tuned to classify the target brain tumors and achieved an accuracy of 98% and an area under the receiver operating characteristics curve (Az) of 0.99. Without pre-trained features, only 61% of accuracy was obtained. The proposed convolutional neural network can accurately and efficiently classify grade 2, 3, and 4 gliomas. The promising accuracy can provide diagnostic suggestions to radiologists in the clinic.

Keywords: convolutional neural network, computer-aided diagnosis, glioblastoma, magnetic resonance imaging

Procedia PDF Downloads 115
120 Internationalization Using Strategic Alliances: A Comparative Study between Family and Non-Family Businesses

Authors: Guadalupe Fuentes-Lombardo, Manuel Carlos Vallejo-Martos, Rubén Fernández-Ortiz, Miriam Cano-Rubio

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The different ways in which companies enter foreign markets, exporting their products and direct investment and using strategic alliances or not, are influenced by a series of peculiarities specific to family businesses. In these companies, different systems, such as the family, property, and business overlap; giving them unique and specific characteristics which on occasions can enhance the development of cooperation agreements and in other situations can hinder them. Previous research has shown that these companies are more likely to enter into strategic alliances with certain specific features, and are more reluctant to take part in others in which some of the advantages of the family business are put at risk, such as control of ownership and decision-making over the company by the family, among others. These arguments show that there is a wide range of interesting aspects and peculiarities in the process of internationalization of the family business, although the research objectives of this paper focus on three in particular. Our first objective will be to discover why family businesses decide to establish or not strategic alliances in their internationalization processes in comparison with other companies that are not family owned. Secondly we will be identifying the idiosyncratic aspects of family businesses that favor or hinder the use of strategic alliances as a means of entering foreign markets. Our third and final objective will be to define the types of strategic alliance most commonly used by family businesses and the reasons why they choose these particular forms of alliance rather than others. We chose these research objectives for three main reasons. Firstly because research on this subject shows that alliances are the best way to begin the international expansion process, among other reasons because they provide the partners with different kinds of resources and capacity, so increasing the probability of successful internationalization. Secondly, because family and non-family businesses are often equipped with different types of resources and strategic alliances, offer them the chance to acquire resources less frequently found in family businesses. Thirdly, because the strengths and weaknesses of these companies could affect their decisions whether or not to use strategic alliances in their international expansion process and the success achieved in these alliances. As a result, these companies prefer to enter into cooperation agreements with conditions that do not put their specific status as family companies at risk.

Keywords: family business, internationalization, strategic alliances, olive-oil and wine industry

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119 Common Regulatory Mechanisms Reveals Links between Aberrant Glycosylation and Biological Hallmarks in Cancer

Authors: Jahanshah Ashkani, Kevin J. Naidoo

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Glycosylation is the major posttranslational modification (PTM) process in cellular development. In tumour development, it is marked by structural alteration of carbohydrates (glycans) that is the result of aberrant glycosylation. Altered glycan structures affect cell surface ligand-receptor interactions that interfere with the regulation of cell adhesion, migration, and proliferation. The resulting changes in glycan biosynthesis pathways originate from altered expression of glycosyltransferases and glycosidases. While the alteration in glycosylation patterns is a recognized “hallmark of cancer”, the influential overview of the biology of cancer proposes eight hallmarks with no explicit suggestion to connectivity with glycosylation. Recently, we have discovered a connection between the glycosyltransferase gene expression and cancer type and subtype. Here we present an association between aberrant glycosylation and the biological hallmarks of breast cancer by exploring the common regulatory mechanisms at the genomic scale. The result of this study bridges the glycobiological and biological pathways that are accepted hallmarks of cancer by connecting their common regulatory pathways. This is an impetus for further investigation as target therapies of breast cancer are very likely to be uncovered from this.

Keywords: aberrant glycosylation, biological hallmarks, breast cancer, regulatory mechanism

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118 Investigation of the Recycling of Geopolymer Cement Wastes as Fine Aggregates in Mortar Mixes

Authors: Napoleana-Anna Chaliasou, Andrew Heath, Kevin Paine

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Fly ash-slag based Geopolymer Cement (GPC) is presenting mechanical properties and environmental advantages that make it the predominant “green” alternative to Portland Cement (PC). Although numerous life-cycle analyses praising its environmental advantages, disposal after the end of its life remains as an issue that has been barely explored. The present study is investigating the recyclability of fly ash-slag GPC as aggregate in mortars. The purpose of the study was to evaluate the effect of GPC fine Recycled Aggregates (RA), at replacement levels of 25% and 50%, on the main mechanical properties of PC and GPC mortar mixes. The results were compared with those obtained by corresponding mixes incorporating natural and PC-RA. The main physical properties of GPC-RA were examined and proven to be comparable to those of PC-RA and slightly inferior to those of natural sand. A negligible effect was observed at 28-day compressive and flexural strength of PC mortars with GPC aggregates having a milder effect than PC. As far as GPC mortars are concerned, the influence of GPC aggregates was enhancing for the investigated mechanical properties. Additionally, a screening test showed that recycled geopolymer aggregates are not prone of inducing alkali silica reaction.

Keywords: concrete recycling, geopolymer cement, fly ash, construction wastes

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117 The Role of Cyfra 21-1 in Diagnosing Non Small Cell Lung Cancer (NSCLC)

Authors: H. J. T. Kevin Mozes, Dyah Purnamasari

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Background: Lung cancer accounted for the fourth most common cancer in Indonesia. 85% of all lung cancer cases are the Non-Small Cell Lung Cancer (NSCLC). The indistinct signs and symptoms of NSCLC sometimes lead to misdiagnosis. The gold standard assessment for the diagnosis of NSCLC is the histopathological biopsy, which is invasive. Cyfra 21-1 is a tumor marker, which can be found in the intermediate protein structure in the epitel. The accuracy of Cyfra 21-1 in diagnosing NSCLC is not yet known, so this report is made to seek the answer for the question above. Methods: Literature searching is done using online databases. Proquest and Pubmed are online databases being used in this report. Then, literature selection is done by excluding and including based on inclusion criterias and exclusion criterias. The selected literature is then being appraised using the criteria of validity, importance, and validity. Results: From six journals appraised, five of them are valid. Sensitivity value acquired from all five literature is ranging from 50-84.5 %, meanwhile the specificity is 87.8 %-94.4 %. Likelihood the ratio of all appraised literature is ranging from 5.09 -10.54, which categorized to Intermediate High. Conclusion: Serum Cyfra 21-1 is a sensitive and very specific tumor marker for diagnosis of non-small cell lung cancer (NSCLC).

Keywords: cyfra 21-1, diagnosis, nonsmall cell lung cancer, NSCLC, tumor marker

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116 Re-Reading the Impossibility of Identity: Modeling Gender Pluralism in Curriculum and Instruction

Authors: A. K. O’Loughlin

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Identity doesn’t exist in discrete categories as it is defined. Kevin Kumashiro reveals the phrase 'an impossibility of identity' in Troubling Education (2000), an investigation of the intersections of culture and gender and the impact of erasure for queer POC identity. This underscores the essentiality of an insider or an outsider identity and the appearance of 'contradiction' or impossibility of these identities. The contradictions between us as subject in our own stories and in the stories of others are often silenced. This silencing of complex, 'contradicting' identity has unmissable implications in the classroom; the developing student in question is done a serious disservice, from which they may never recover. There is no more important point of contact than the teacher, for willingness to encounter a developing person as they are, not as we already think they are, or 'know' them to be, or think they should be. To decide how to regard them based on our own unilateral identity and its associated exhortations and injunctions is, as Hannah Arendt writes in The Origins of Totalitarianism (1951), to sell off our ability to rise, human-like, to the challenge of investigating things as they are. A re-reading of Kumashiro’s impossibility of identity becomes possible through the investigation of pluralism. Identities become possible and un-paradoxical by the notion that contradictions are not problems that an individual is not unilateral, but plural. In this paper, we investigate how philosophies of pluralism can inform our understanding of impossibility of identity in classroom curriculum and pedagogy.

Keywords: identity, gender, culture, pluralism, education, philosophy of education, queer theory, philosophy of mind, adolescent development

Procedia PDF Downloads 261
115 A Case Study of Deep Learning for Disease Detection in Crops

Authors: Felipe A. Guth, Shane Ward, Kevin McDonnell

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In the precision agriculture area, one of the main tasks is the automated detection of diseases in crops. Machine Learning algorithms have been studied in recent decades for such tasks in view of their potential for improving economic outcomes that automated disease detection may attain over crop fields. The latest generation of deep learning convolution neural networks has presented significant results in the area of image classification. In this way, this work has tested the implementation of an architecture of deep learning convolution neural network for the detection of diseases in different types of crops. A data augmentation strategy was used to meet the requirements of the algorithm implemented with a deep learning framework. Two test scenarios were deployed. The first scenario implemented a neural network under images extracted from a controlled environment while the second one took images both from the field and the controlled environment. The results evaluated the generalisation capacity of the neural networks in relation to the two types of images presented. Results yielded a general classification accuracy of 59% in scenario 1 and 96% in scenario 2.

Keywords: convolutional neural networks, deep learning, disease detection, precision agriculture

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114 Improving Decision Support for Organ Transplant

Authors: Ian McCulloh, Andrew Placona, Darren Stewart, Daniel Gause, Kevin Kiernan, Morgan Stuart, Christopher Zinner, Laura Cartwright

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An estimated 22-25% of viable deceased donor kidneys are discarded every year in the US, while waitlisted candidates are dying every day. As many as 85% of transplanted organs are refused at least once for a patient that scored higher on the match list. There are hundreds of clinical variables involved in making a clinical transplant decision and there is rarely an ideal match. Decision makers exhibit an optimism bias where they may refuse an organ offer assuming a better match is imminent. We propose a semi-parametric Cox proportional hazard model, augmented by an accelerated failure time model based on patient specific suitable organ supply and demand to estimate a time-to-next-offer. Performance is assessed with Cox-Snell residuals and decision curve analysis, demonstrating improved decision support for up to a 5-year outlook. Providing clinical decision makers with quantitative evidence of likely patient outcomes (e.g., time to next offer and the mortality associated with waiting) may improve decisions and reduce optimism bias, thus reducing discarded organs and matching more patients on the waitlist.

Keywords: decision science, KDPI, optimism bias, organ transplant

Procedia PDF Downloads 65
113 Being a Teacher in Higher Education: Techne or Praxis

Authors: Thi V. S. Nguyen, Kevin Laws

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This study investigates the construction of higher education teachers’ roles from the perspectives of participants in a compulsory teachers’ professional development for Vietnamese higher education teachers. Constructivist grounded theory was used as methodology and analysis of the study. Fifteen program participants were semi-structured interviewed before they started the professional development program for higher education teachers. Five trainers of the program were interviewed and documents related to teachers’ standards in Vietnam were analysed to supplement participants’ perspectives. Standards and roles of higher education teachers emerged as two categories grounded from data. Standard category involves moral and professional criteria, whereas roles of higher education teachers category consists of specific roles related to guiding student learning, and advising their academic, moral and social activities. A model of higher education teachers’ conceptions of their roles in a Vietnamese context addressing both professional (techne) and moral (praxis) responsibilities is constructed from this study. A discussion on teachers’ roles in higher education is put forward and insightful implications for the design and possible restructure of teachers’ professional development for early career higher education teachers is suggested.

Keywords: higher education teachers' roles and standards, moral roles, teachers' professional development, teachers' conceptions of their roles

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112 Minimum-Fuel Optimal Trajectory for Reusable First-Stage Rocket Landing Using Particle Swarm Optimization

Authors: Kevin Spencer G. Anglim, Zhenyu Zhang, Qingbin Gao

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Reusable launch vehicles (RLVs) present a more environmentally-friendly approach to accessing space when compared to traditional launch vehicles that are discarded after each flight. This paper studies the recyclable nature of RLVs by presenting a solution method for determining minimum-fuel optimal trajectories using principles from optimal control theory and particle swarm optimization (PSO). This problem is formulated as a minimum-landing error powered descent problem where it is desired to move the RLV from a fixed set of initial conditions to three different sets of terminal conditions. However, unlike other powered descent studies, this paper considers the highly nonlinear effects caused by atmospheric drag, which are often ignored for studies on the Moon or on Mars. Rather than optimizing the controls directly, the throttle control is assumed to be bang-off-bang with a predetermined thrust direction for each phase of flight. The PSO method is verified in a one-dimensional comparison study, and it is then applied to the two-dimensional cases, the results of which are illustrated.

Keywords: minimum-fuel optimal trajectory, particle swarm optimization, reusable rocket, SpaceX

Procedia PDF Downloads 243
111 Geophysical Contribution to Reveal the Subsurface Structural Setting Using Gravity, Seismic and Seismological Data in the Chott Belts, Southern Atlas of Tunisia

Authors: Nesrine Frifita, Mohamed Gharbi, Kevin Mickus

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Physical methods based on gravity, seismic and seismological data were adopted to clarify the relationship between the distribution of seismicity and the crustal deformations under the chott belts and surrounding regions, in southern atlas of Tunisia. Gafsa and its surrounding were described as a moderate seismic zone, and the fault of Gafsa is one of most seismically active faults in Tunisia in general, and in the southern Atlas in particularly. The present work aims to prove a logical relationship between the distribution of seismicity and deformations which strongly related to thickness and density variations within the basement and sedimentary cover along the study area, through several physical methods; gravity, seismic and seismological data were interpreted to calculate physical propriety of the subsurface rocks, the depth and geometry of active faults and causatives bodies. Findings show that depths variation and mixed thin and thick skinned structural style characterizing the chott belts explain the moderate seismicity in the study area.

Keywords: potential fields, seismicity, Southern Atlas, Tunisia

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110 Inherited Intergenerational Trauma – The Society for Black People in South Central Los Angeles

Authors: Kevin R. Collins Sr.

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In South Central Los Angeles, Black people have endured various forms of trauma that spans across generations. This includes the horrors of slavery and the aftermaths of the Jim Crow Laws, institutionalized racism, and legislative segregation, just to name a few. The individuals born from the 1900’s until today have continued to transmit the traumas experienced across generations. Parents unconsciously transmit the hidden trauma, and the children take these experiences and apply it to the society they live in. Although there are some who attempt to break the cycle of transmitted trauma, the remninsce still remain and play a huge role in how they interact with others. The attempt of this discussion is to bring these traumatic experiences to the surface and attack them head on. It is important that we do this to allow not only the suffering individuals but the suffering society to heal. As a society, looking at the humane side of it and attempting to stop the racial injustice placed on black people to relieve them of the stress that some. If not all,, endure in this great United States of America. Changing the behavior as a country to create an improved since of common unity within. If we solve our own racial and social issues within this country, maybe we can solve these same issues that have been the footstool to the many wars we see around the world. Thus, breaking the cycle of inherited intergenerational trauma.

Keywords: intergenerational trauma, inherited trauma, transmission of trauma, blacks in South central LA, black trauma in America

Procedia PDF Downloads 63
109 Improvement of Parallel Compressor Model in Dealing Outlet Unequal Pressure Distribution

Authors: Kewei Xu, Jens Friedrich, Kevin Dwinger, Wei Fan, Xijin Zhang

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Parallel Compressor Model (PCM) is a simplified approach to predict compressor performance with inlet distortions. In PCM calculation, it is assumed that the sub-compressors’ outlet static pressure is uniform and therefore simplifies PCM calculation procedure. However, if the compressor’s outlet duct is not long and straight, such assumption frequently induces error ranging from 10% to 15%. This paper provides a revised calculation method of PCM that can correct the error. The revised method employs energy equation, momentum equation and continuity equation to acquire needed parameters and replace the equal static pressure assumption. Based on the revised method, PCM is applied on two compression system with different blades types. The predictions of their performance in non-uniform inlet conditions are yielded through the revised calculation method and are employed to evaluate the method’s efficiency. Validating the results by experimental data, it is found that although little deviation occurs, calculated result agrees well with experiment data whose error ranges from 0.1% to 3%. Therefore, this proves the revised calculation method of PCM possesses great advantages in predicting the performance of the distorted compressor with limited exhaust duct.

Keywords: parallel compressor model (pcm), revised calculation method, inlet distortion, outlet unequal pressure distribution

Procedia PDF Downloads 300
108 Classification of Myoelectric Signals Using Multilayer Perceptron Neural Network with Back-Propagation Algorithm in a Wireless Surface Myoelectric Prosthesis of the Upper-Limb

Authors: Kevin D. Manalo, Jumelyn L. Torres, Noel B. Linsangan

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This paper focuses on a wireless myoelectric prosthesis of the upper-limb that uses a Multilayer Perceptron Neural network with back propagation. The algorithm is widely used in pattern recognition. The network can be used to train signals and be able to use it in performing a function on their own based on sample inputs. The paper makes use of the Neural Network in classifying the electromyography signal that is produced by the muscle in the amputee’s skin surface. The gathered data will be passed on through the Classification Stage wirelessly through Zigbee Technology. The signal will be classified and trained to be used in performing the arm positions in the prosthesis. Through programming using Verilog and using a Field Programmable Gate Array (FPGA) with Zigbee, the EMG signals will be acquired and will be used for classification. The classified signal is used to produce the corresponding Hand Movements (Open, Pick, Hold, and Grip) through the Zigbee controller. The data will then be processed through the MLP Neural Network using MATLAB which then be used for the surface myoelectric prosthesis. Z-test will be used to display the output acquired from using the neural network.

Keywords: field programmable gate array, multilayer perceptron neural network, verilog, zigbee

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107 Effect on Body Weight of Naltrexone/Bupropion in Overweight and Obese Participants with Cardiovascular Risk Factors in a Large Randomized Double-Blind Study

Authors: Amy Halseth, Kevin Shan, Kye Gilder, John Buse

Abstract:

The study assessed the effect of prolonged-release naltrexone 32 mg/bupropion 360 mg (NB) on cardiovascular (CV) events in overweight/obese participants at elevated CV risk. Participants must lose ≥ 2% body weight at 16 wks, without a sustained increase in blood pressure, to continue drug. The study was terminated early after second interim analysis with 50% of all CV events. Data on CV endpoints has been published. Current analyses focus on weight change. Intent-to-treat (ITT) population (placebo [PBO] N=4450, NB N=4455) was 54.5% female, 83.5% white, mean age 61 yrs, mean BMI 37.3 kg/m2; 85.2% had type 2 diabetes, 32.1% had CV disease, 17.4% had both. At 52 wks, ITT-LOCF analysis showed greater least squares mean percent change in weight (LSM%ΔBW) with NB (-3.1%; 95% CI -4.8, -1.4) vs PBO (-0.3%; 95% CI -1.9, 1.4). Both groups demonstrated greater weight loss while on-treatment (NB [-7.3%], PBO [-3.9%]). Odds ratios of 5% and 10% weight loss were 3.3 and 4.1 (ITT-LOCF), respectively, in NB over PBO. At 104 wks, on-treatment LSM%ΔBW was -6.3% with NB (n=1137) vs -3.5% with PBO (n=741). Major reasons for NB withdrawal were adverse events (AE, 29%) and patient decision (21%), with GI disorders being the most common. Weight loss with NB in this study, in an older population predominantly with diabetes and elevated CV risk, was somewhat lower than that observed in overweight/obese participants without diabetes and similar to participants with diabetes in Phase 3 studies.

Keywords: contrave, mysimba, obesity, pharmacotherapy, weight loss

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106 Vibration Analysis of a Solar Powered UAV

Authors: Kevin Anderson, Sukhwinder Singh Sandhu, Nouh Anies, Shilpa Ravichandra, Steven Dobbs, Donald Edberg

Abstract:

This paper presents the results of a Finite Element based vibration analysis of a solar powered Unmanned Aerial Vehicle (UAV). The purpose of this paper was to quantify the free vibration, forced vibration response due to differing point inputs in order to mimic the vibration induced by actuators (magnet in coil generators) used to aid in the flight of the UAV. A Fluid-Structure Interaction (FSI) study was performed in order to ascertain pertinent deigns stresses and deflections as well as aerodynamic parameters of the UAV airfoil. The 10 ft span airfoil is modeled using Mylar as the primary material. Results show that the free mode in bending is 4.8 Hz while the first forced bending mode is in the range of 16.2 to 16.7 Hz depending on the location of excitation. The free torsional bending mode is 28.3 Hz, and the first forced torsional mode is in the range of 26.4 to 27.8 Hz, depending on the location of excitation. The FSI results predict the coefficients of aerodynamic drag and lift of 0.0052 and 0.077, respectively, which matches hand-calculations used to validate the Finite Element based results. FSI based maximum von Mises stresses and deflections were found to be 0.282 MPa and 3.4 mm, respectively. Dynamic pressures on the airfoil range of 1.04 to 1.23 kPa corresponding to velocity magnitudes in the range of 22 to 66 m/s.

Keywords: ANSYS, finite element, FSI, UAV, vibrations

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105 Effect on Tolerability and Adverse Events in Participants Receiving Naltrexone/Bupropion and Antidepressant Medication, Including SSRIs, in a Large Randomized Double-Blind Study

Authors: Kye Gilder, Kevin Shan, Amy Halseth, Steve Smith

Abstract:

This study assessed the effect of prolonged-release naltrexone 32 mg/bupropion 360 mg (NB) on cardiovascular (CV) events in overweight/obese participants at elevated CV risk. Participants must lose ≥2% body weight at 16 wks, without a sustained increase in blood pressure, to continue drug. Only serious adverse events (SAE) and adverse events leading to discontinuation of study drug (AELDSD) were collected. The study was terminated early after second interim analysis with 50% of all CV events. Data on CV endpoints has been published. Current analyses focused on AEs in participants on antidepressants at baseline, as these individuals were excluded from Phase 3 trials. Intent-to-treat (ITT) population (placebo [PBO] N=4450, NB N=4455) was 54.5% female, 83.5% white, mean age of 61 yrs, mean BMI 37.3 kg/m2, 22.8% with a history of depression, 23.1% on antidepressants, including 15.4% on an SSRI. SAEs in participants receiving antidepressants was similar between NB (10.7%) and PBO (9.9%) and also similar to overall population (9.5% NB, 8.1% PBO). SAEs in those on SSRIs were similar, 10.1% NB and PBO 9.4%. For those on SSRIs or other antidepressants, AELDSDs were similar to overall population and were primarily GI disorders. Obesity increases the risk of developing depression. For participants taking NB and antidepressants, including SSRIs, there is a similar AE profile as the overall population and data revealed no evidence of an additional health risk with combined use.

Keywords: antidepressant, Contrave, Mysimba, obesity, pharmacotherapy

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104 Audience Perceptions and Attitudes Towards the Representation of Tribal South African Culture in Drama Series

Authors: Oluwayemisi Mary Onyenanakeya, Kevin Onyenankeya

Abstract:

Commercial media entertainment offerings especially mainstream soap operas, in South Africa, are progressively infusing dominant social values and ideas which are alien to South African tribal societies. In most of the commodified television drama series, people who hold tight to traditional beliefs and values are often characterised as traditionalists, while those who have imbibed the western defined dicta and ideology of modernity are seen as progressives. This study, therefore, sought to ascertain how South African tribal language, traditional institutions, values, social norms and ancestral beliefs are portrayed through the television drama, Generations: The Legacy, and what the viewers think about those constructions and the implication for cultural identity. The mixed methods approach was employed involving the administration of questionnaire to 350 participants selected through random sampling and a content analysis of 20 episodes of Generations: The Legacy. The findings further showed that the values and traditions represented in generation do not significantly reflect the South African tribal tradition and values (p-value > 0.05). In most instances where traditional values are represented they tend to be portrayed as old fashioned (p-value > 0.05), and inferior and backward (p-value > 0.05). In addition, the findings indicate that Generations: The legacy is a vehicle for promoting dominant culture.

Keywords: identity, soap opera, South Africa, television

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103 Design and Implementation of a Counting and Differentiation System for Vehicles through Video Processing

Authors: Derlis Gregor, Kevin Cikel, Mario Arzamendia, Raúl Gregor

Abstract:

This paper presents a self-sustaining mobile system for counting and classification of vehicles through processing video. It proposes a counting and classification algorithm divided in four steps that can be executed multiple times in parallel in a SBC (Single Board Computer), like the Raspberry Pi 2, in such a way that it can be implemented in real time. The first step of the proposed algorithm limits the zone of the image that it will be processed. The second step performs the detection of the mobile objects using a BGS (Background Subtraction) algorithm based on the GMM (Gaussian Mixture Model), as well as a shadow removal algorithm using physical-based features, followed by morphological operations. In the first step the vehicle detection will be performed by using edge detection algorithms and the vehicle following through Kalman filters. The last step of the proposed algorithm registers the vehicle passing and performs their classification according to their areas. An auto-sustainable system is proposed, powered by batteries and photovoltaic solar panels, and the data transmission is done through GPRS (General Packet Radio Service)eliminating the need of using external cable, which will facilitate it deployment and translation to any location where it could operate. The self-sustaining trailer will allow the counting and classification of vehicles in specific zones with difficult access.

Keywords: intelligent transportation system, object detection, vehicle couting, vehicle classification, video processing

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102 A Review on Using Executive Function to Understand the Limited Efficacy of Weight-Loss Interventions

Authors: H. Soltani, Kevin Laugero

Abstract:

Obesity is becoming an increasingly critical issue in the United States due to the steady and substantial increase in prevalence over the last 30 years. Existing interventions have been able to help participants achieve short-term weight loss, but have failed to show long-term results. The complex nature of behavioral change remains one of the most difficult barriers in promoting sustainable weight-loss in overweight individuals. Research suggests that the 'intention-behavior gap' can be explained by a person’s ability to regulate higher-order thinking, or Executive Function (EF). A review of 63 research articles was completed in fall of 2017 to identify the role of EF in regulating eating behavior and to identify whether there is a potential for improving dietary quality by enhancing EF. Results showed that poor EF is positively associated with obesogenic behavior, namely increased consumption of highly palatable foods, eating in the absence of hunger, high saturated fat intake and low fruit and vegetable consumption. Recent research has indicated that interventions targeting an improvement in EF can be successful in helping promote healthy behaviors. Furthermore, interventions of longer duration have a more lasting and versatile effect on weight loss and maintenance. This may present an opportunity for the increasingly ubiquitous use of mobile application technology.

Keywords: eating behavior, executive function, nutrition, obesity, weight-loss

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101 Design and Application of a Model Eliciting Activity with Civil Engineering Students on Binomial Distribution to Solve a Decision Problem Based on Samples Data Involving Aspects of Randomness and Proportionality

Authors: Martha E. Aguiar-Barrera, Humberto Gutierrez-Pulido, Veronica Vargas-Alejo

Abstract:

Identifying and modeling random phenomena is a fundamental cognitive process to understand and transform reality. Recognizing situations governed by chance and giving them a scientific interpretation, without being carried away by beliefs or intuitions, is a basic training for citizens. Hence the importance of generating teaching-learning processes, supported using technology, paying attention to model creation rather than only executing mathematical calculations. In order to develop the student's knowledge about basic probability distributions and decision making; in this work a model eliciting activity (MEA) is reported. The intention was applying the Model and Modeling Perspective to design an activity related to civil engineering that would be understandable for students, while involving them in its solution. Furthermore, the activity should imply a decision-making challenge based on sample data, and the use of the computer should be considered. The activity was designed considering the six design principles for MEA proposed by Lesh and collaborators. These are model construction, reality, self-evaluation, model documentation, shareable and reusable, and prototype. The application and refinement of the activity was carried out during three school cycles in the Probability and Statistics class for Civil Engineering students at the University of Guadalajara. The analysis of the way in which the students sought to solve the activity was made using audio and video recordings, as well as with the individual and team reports of the students. The information obtained was categorized according to the activity phase (individual or team) and the category of analysis (sample, linearity, probability, distributions, mechanization, and decision-making). With the results obtained through the MEA, four obstacles have been identified to understand and apply the binomial distribution: the first one was the resistance of the student to move from the linear to the probabilistic model; the second one, the difficulty of visualizing (infering) the behavior of the population through the sample data; the third one, viewing the sample as an isolated event and not as part of a random process that must be viewed in the context of a probability distribution; and the fourth one, the difficulty of decision-making with the support of probabilistic calculations. These obstacles have also been identified in literature on the teaching of probability and statistics. Recognizing these concepts as obstacles to understanding probability distributions, and that these do not change after an intervention, allows for the modification of these interventions and the MEA. In such a way, the students may identify themselves the erroneous solutions when they carrying out the MEA. The MEA also showed to be democratic since several students who had little participation and low grades in the first units, improved their participation. Regarding the use of the computer, the RStudio software was useful in several tasks, for example in such as plotting the probability distributions and to exploring different sample sizes. In conclusion, with the models created to solve the MEA, the Civil Engineering students improved their probabilistic knowledge and understanding of fundamental concepts such as sample, population, and probability distribution.

Keywords: linear model, models and modeling, probability, randomness, sample

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