Search results for: Thomas Wong
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 621

Search results for: Thomas Wong

291 An Eulerian Method for Fluid-Structure Interaction Simulation Applied to Wave Damping by Elastic Structures

Authors: Julien Deborde, Thomas Milcent, Stéphane Glockner, Pierre Lubin

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A fully Eulerian method is developed to solve the problem of fluid-elastic structure interactions based on a 1-fluid method. The interface between the fluid and the elastic structure is captured by a level set function, advected by the fluid velocity and solved with a WENO 5 scheme. The elastic deformations are computed in an Eulerian framework thanks to the backward characteristics. We use the Neo Hookean or Mooney Rivlin hyperelastic models and the elastic forces are incorporated as a source term in the incompressible Navier-Stokes equations. The velocity/pressure coupling is solved with a pressure-correction method and the equations are discretized by finite volume schemes on a Cartesian grid. The main difficulty resides in that large deformations in the fluid cause numerical instabilities. In order to avoid these problems, we use a re-initialization process for the level set and linear extrapolation of the backward characteristics. First, we verify and validate our approach on several test cases, including the benchmark of FSI proposed by Turek. Next, we apply this method to study the wave damping phenomenon which is a mean to reduce the waves impact on the coastline. So far, to our knowledge, only simulations with rigid or one dimensional elastic structure has been studied in the literature. We propose to place elastic structures on the seabed and we present results where 50 % of waves energy is absorbed.

Keywords: damping wave, Eulerian formulation, finite volume, fluid structure interaction, hyperelastic material

Procedia PDF Downloads 317
290 The Science of Dreaming and Sleep in Selected Charles Dickens' Novels and Letters

Authors: Olga Colbert

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The present work examines the representation of dreaming in Charles Dickens’ novels, particularly Oliver Twist. Dickens showed great interest in the science of dreaming and had ample knowledge of the latest dream theories in the Victorian era, as can be seen in his personal correspondence, most notably in his famous letter to Dr. Thomas Stone on 2/2/1851. This essay places Dickens’ personal writings side by side with his novels to elucidate whether the scientific paradigm about dreaming included in the novel is consistent with the current (in Dickens’ time) scientific knowledge, or whether it is anachronistic or visionary (ahead of his time). Oliver Twist is particularly useful because it contains entire passages pondering on the nature of dreaming, enumerating types of common dreams, and taking a stand on the interference of sensory perception during the dreaming state. The author is particularly intrigued by Dickens’ assumption of the commonality and universality of lucid dreaming as revealed in these passages. This essay places popular Victorian dream theories, such as those contained in Robert Macnish’s The Philosophy of Sleep, side by side with recent dream theory, particularly psychophysiologist Stephen LaBerge’s numerous articles and books on the topic of lucid dreaming to see if Dickens deviated in any way from the reigning paradigm of the Victorian era in his representation of dreaming in his novels. While Dickens puts to great narrative use many of the characteristics of dreaming described by leading Victorian theorists, the author of this study argues, however, that Dickens’ most visionary statements derive from his acute observations of his own dreaming experiences.

Keywords: consciousness, Dickens, dreaming, lucid dreaming, Victorian

Procedia PDF Downloads 284
289 Recycled Aggregates from Construction and Demolition Waste in the Production of Concrete Blocks

Authors: Juan A. Ferriz-Papi, Simon Thomas

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The construction industry generates large amounts of waste, usually mixed, which can be composed of different origin materials, most of them catalogued as non-hazardous. The European Union targets for this waste for 2020 have been already achieved by the UK, but it is mainly developed in downcycling processes (backfilling) whereas upcycling (such as recycle in new concrete batches) still keeps at a low percentage. The aim of this paper is to explore further in the use of recycled aggregates from construction and demolition waste (CDW) in concrete mixes so as to improve upcycling. A review of most recent research and legislation applied in the UK is developed regarding the production of concrete blocks. As a case study, initial tests were developed with a CDW recycled aggregate sample from a CDW plant in Swansea. Composition by visual inspection and sieving tests of two samples were developed and compared to original aggregates. More than 70% was formed by soil waste from excavation, and the rest was a mix of waste from mortar, concrete, and ceramics with small traces of plaster, glass and organic matter. Two concrete mixes were made with 80% replacement of recycled aggregates and different water/cement ratio. Tests were carried out for slump, absorption, density and compression strength. The results were compared to a reference sample and showed a substantial reduction of quality in both mixes. Despite that, the discussion brings to identify different aspects to solve, such as heterogeneity or composition, and analyze them for the successful use of these recycled aggregates in the production of concrete blocks. The conclusions obtained can help increase upcycling processes ratio with mixed CDW as recycled aggregates in concrete mixes.

Keywords: aggregates, concrete, concrete block, construction and demolition waste, recycling

Procedia PDF Downloads 295
288 Nutritional Evaluation and the Importance of Traditional Vegetables That Sustain the Indigenous People of Malaysia

Authors: Rachel Thomas Tharmabalan

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The growing unease over the matter of food security in the world is the result of a maturing realization that the genetic base of most human caloric intake from plants is dangerously narrow. Malaysia’s tropical rainforests have the potential to contribute to diet diversification and provide a source of nutrient-rich food as the Orang Asli communities in Malaysia have relied almost entirely on the jungle for food, fodder, medicine and fuel antithetical to what is happening today. This segregation of the Orang Asli from traditional lands and resources leads to severe loss of knowledge of biodiversity. In order to preserve these wild edibles, four different types of vegetables that are frequently consumed by the Orang Asli which consists of Rebu, Meranti, Saya and Pama were selected. These vegetables were then analysed to determine its proximate and mineral content to help ascertain claims and reaffirm the impact it can play in ensuring food and nutrition security, in addition to combating chronic diseases. From the results obtained, the Meranti had the highest crude fiber, iron and calcium content. Other minerals such as potassium, magnesium and copper were also found in varying content. These wild edibles could also contribute to education and bring awareness to younger generations as well as urban populations to start consuming more of these in their daily life as it could prevent various chronic diseases in Malaysia.

Keywords: food and nutrition security, Orang Asli, underutilized plants, wild edible food systems

Procedia PDF Downloads 148
287 Asymmetric Price Transmission in Rice: A Regional Analysis in Peru

Authors: Renzo Munoz-Najar, Cristina Wong, Daniel De La Torre Ugarte

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The literature on price transmission usually deals with asymmetries related to different commodities and/or the short and long term. The role of domestic regional differences and the relationship with asymmetries within a country are usually left out. This paper looks at the asymmetry in the transmission of rice prices from the international price to the farm gate prices in four northern regions of Peru for the last period 2001-2016. These regions are San Martín, Piura, Lambayeque and La Libertad. The relevance of the study lies in its ability to assess the need for policies aimed at improving the competitiveness of the market and ensuring the benefit of producers. There are differences in planting and harvesting dates, as well as in geographic location that justify the hypothesis of the existence of differences in the price transition asymmetries between these regions. Those differences are due to at least three factors geography, infrastructure development, and distribution systems. For this, the Threshold Vector Error Correction Model and the Autoregressive Vector Model with Threshold are used. Both models, collect asymmetric effects in the price adjustments. In this way, it is sought to verify that farm prices react more to falls than increases in international prices due to the high bargaining power of intermediaries. The results of the investigation suggest that the transmission of prices is significant only for Lambayeque and La Libertad. Likewise, the asymmetry in the transmission of prices for these regions is checked. However, these results are not met for San Martin and Piura, the main rice producers nationwide. A significant price transmission is verified only in the Lambayeque and La Libertad regions. San Martin and Piura, in spite of being the main rice producing regions of Peru, do not present a significant transmission of international prices; a high degree of self-sufficient supply might be at the center of the logic for this result. An additional finding is the short-term adjustment with respect to international prices, it is higher in La Libertad compared to Lambayeque, which could be explained by the greater bargaining power of intermediaries in the last-mentioned region due to the greater technological development in the mills.

Keywords: asymmetric price transmission, rice prices, price transmission, regional economics

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286 Evaluation of Modulus of Elasticity by Non-Destructive Method of Hybrid Fiber Reinforced Concrete

Authors: Erjola Reufi, Thomas Beer

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Plain, unreinforced concrete is a brittle material, with a low tensile strength, limited ductility and little resistance to cracking. In order to improve the inherent tensile strength of concrete there is a need of multi directional and closely spaced reinforcement, which can be provided in the form of randomly distributed fibers. Fiber reinforced concrete (FRC) is a composite material consisting of cement, sand, coarse aggregate, water and fibers. In this composite material, short discrete fibers are randomly distributed throughout the concrete mass. The behavioral efficiency of this composite material is far superior to that of plain concrete and many other construction materials of equal cost. The present experimental study considers the effect of steel fibers and polypropylene fiber on the modulus of elasticity of concrete. Hook end steel fibers of length 5 cm and 3 cm at volume fraction of 0.25%, 0.5% and 1.% were used. Also polypropylene fiber of length 12, 6, 3 mm at volume fraction 0.1, 0.25, and 0.4 % were used. Fifteen mixtures has been prepared to evaluate the effect of fiber on modulus of elasticity of concrete. Ultrasonic pulse velocity (UPV) and resonant frequency methods which are two non-destructive testing techniques have been used to measure the elastic properties of fiber reinforced concrete. This study found that ultrasonic wave propagation is the most reliable, easy and cost effective testing technique to use in the determination of the elastic properties of the FRC mix used in this study.

Keywords: fiber reinforced concrete(FRC), polypropylene fiber, resonance, ultrasonic pulse velocity, steel fiber

Procedia PDF Downloads 297
285 Children and Migration in Ghana: Unveiling the Realities of Vulnerability and Social Exclusion

Authors: Thomas Yeboah

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In contemporary times, the incessant movement of northern children especially girls to southern Ghana at the detriment of their education is worrisome. Due to the misplaced mindset of the migrants concerning southern Ghana, majority of them move without an idea of where to stay and what to do exposing them to hash conditions of living. Majority find menial work in cocoa farms, illegal mining and head porterage business. This study was conducted in the Kumasi Metropolis to ascertain the major causes of child migration from the northern part of Ghana to the south and their living conditions. Both qualitative and quantitative tools of data collection and analysis were employed. The purposive sampling technique was used to select 90 migrants below 18 years. Specifically, interviews, focus group discussions and questionnaires were used to elicit responses from the units of analysis. The study revealed that the major cause of child migration from northern Ghana to the south is poverty. It was evident that respondents were vulnerable to the new environment in which they lived. They are exposed to harsh environmental conditions; sexual, verbal and physical assault; and harassment from arm robbers. The paper recommends that policy decisions should be able to create an enabling environment for the labour force in the north to ameliorate the compelling effects poverty has on child migration. Efforts should also be made to create a proper psychological climate in the minds of the children regarding their destination areas through sensitization and education.

Keywords: child migration, vulnerability, social exclusion, child labour, Ghana

Procedia PDF Downloads 438
284 Periplasmic Expression of Anti-RoxP Antibody Fragments in Escherichia Coli.

Authors: Caspar S. Carson, Gabriel W. Prather, Nicholas E. Wong, Jeffery R. Anton, William H. McCoy

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Cutibacterium acnes is a commensal bacterium found on human skin that has been linked to acne. C. acnes can also be an opportunistic pathogen when it infiltrates the body during surgery. This pathogen can cause dangerous infections of medical implants, such as shoulder replacements, leading to life-threatening blood infections. Compounding this issue, C. acnes resistance to many antibiotics has become an increasing problem worldwide, creating a need for special forms of treatment. C. acnes expresses the protein RoxP, and it requires this protein to colonize human skin. Though this protein is required for C. acnes skin colonization, its function is not yet understood. Inhibition of RoxP function might be an effective treatment for C. acnes infections. To develop such reagents, the McCoy Laboratory generated four unique anti-RoxP antibodies. Preliminary studies in the McCoy Lab have established that each antibody binds a distinct site on RoxP. To assess the potential of these antibodies as therapeutics, it is necessary to specifically characterize these antibody epitopes and evaluate them in assays that assess their ability to inhibit RoxP-dependent C. acnes growth. To provide material for these studies, an antibody expression construct, Fv-clasp(v2), was adapted to encode anti-RoxP antibody sequences. The author hypothesizes that this expression strategy can produce sufficient amounts of >95% pure antibody fragments for further characterization of these antibodies. Four anti-RoxP Fv-clasp(v2) expression constructs (pET vector-based) were transformed into E. coli BL21-Gold(DE3) cells and a small-scale expression and purification trial was performed for each construct to evaluate anti-RoxP Fv-clasp(v2) yield and purity. Successful expression and purification of these antibody constructs will allow for their use in structural studies, such as protein crystallography and cryogenic electron microscopy. Such studies would help to define the antibody binding sites on RoxP, which could then be leveraged in the development of certain methods to treat C. acnes infection through RoxP inhibition.

Keywords: structural biology, protein expression, infectious disease, antibody, therapeutics, E. coli

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283 Fast Approximate Bayesian Contextual Cold Start Learning (FAB-COST)

Authors: Jack R. McKenzie, Peter A. Appleby, Thomas House, Neil Walton

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Cold-start is a notoriously difficult problem which can occur in recommendation systems, and arises when there is insufficient information to draw inferences for users or items. To address this challenge, a contextual bandit algorithm – the Fast Approximate Bayesian Contextual Cold Start Learning algorithm (FAB-COST) – is proposed, which is designed to provide improved accuracy compared to the traditionally used Laplace approximation in the logistic contextual bandit, while controlling both algorithmic complexity and computational cost. To this end, FAB-COST uses a combination of two moment projection variational methods: Expectation Propagation (EP), which performs well at the cold start, but becomes slow as the amount of data increases; and Assumed Density Filtering (ADF), which has slower growth of computational cost with data size but requires more data to obtain an acceptable level of accuracy. By switching from EP to ADF when the dataset becomes large, it is able to exploit their complementary strengths. The empirical justification for FAB-COST is presented, and systematically compared to other approaches on simulated data. In a benchmark against the Laplace approximation on real data consisting of over 670, 000 impressions from autotrader.co.uk, FAB-COST demonstrates at one point increase of over 16% in user clicks. On the basis of these results, it is argued that FAB-COST is likely to be an attractive approach to cold-start recommendation systems in a variety of contexts.

Keywords: cold-start learning, expectation propagation, multi-armed bandits, Thompson Sampling, variational inference

Procedia PDF Downloads 105
282 Evaluation of Public Library Adult Programs: Use of Servqual and Nippa Assessment Standards

Authors: Anna Ching-Yu Wong

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This study aims to identify the quality and effectiveness of the adult programs provided by the public library using the ServQUAL Method and the National Library Public Programs Assessment guidelines (NIPPA, June 2019). ServQUAl covers several variables, namely: tangible, reliability, responsiveness, assurance, and empathy. NIPPA guidelines focus on program characteristics, particularly on the outcomes – the level of satisfaction from program participants. The reached populations were adults who participated in library adult programs at a small-town public library in Kansas. This study was designed as quantitative evaluative research which analyzed the quality and effectiveness of the library adult programs by analyzing the role of each factor based on ServQUAL and the NIPPA's library program assessment guidelines. Data were collected from November 2019 to January 2020 using a questionnaire with a Likert Scale. The data obtained were analyzed in a descriptive quantitative manner. The impact of this research can provide information about the quality and effectiveness of existing programs and can be used as input to develop strategies for developing future adult programs. Overall the result of ServQUAL measurement is in very good quality, but still, areas need improvement and emphasis in each variable: Tangible Variables still need improvement in indicators of the temperature and space of the meeting room. Reliability Variable still needs improvement in the timely delivery of the programs. Responsiveness Variable still needs improvement in terms of the ability of the presenters to convey trust and confidence from participants. Assurance Variables still need improvement in the indicator of knowledge and skills of program presenters. Empathy Variable still needs improvement in terms of the presenters' willingness to provide extra assistance. The result of program outcomes measurement based on NIPPA guidelines is very positive. Over 96% of participants indicated that the programs were informative and fun. They learned new knowledge and new skills and would recommend the programs to their friends and families. They believed that together, the library and participants build stronger and healthier communities.

Keywords: ServQual model, ServQual in public libraries, library program assessment, NIPPA library programs assessment

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281 A Flute Tracking System for Monitoring the Wear of Cutting Tools in Milling Operations

Authors: Hatim Laalej, Salvador Sumohano-Verdeja, Thomas McLeay

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Monitoring of tool wear in milling operations is essential for achieving the desired dimensional accuracy and surface finish of a machined workpiece. Although there are numerous statistical models and artificial intelligence techniques available for monitoring the wear of cutting tools, these techniques cannot pin point which cutting edge of the tool, or which insert in the case of indexable tooling, is worn or broken. Currently, the task of monitoring the wear on the tool cutting edges is carried out by the operator who performs a manual inspection, causing undesirable stoppages of machine tools and consequently resulting in costs incurred from lost productivity. The present study is concerned with the development of a flute tracking system to segment signals related to each physical flute of a cutter with three flutes used in an end milling operation. The purpose of the system is to monitor the cutting condition for individual flutes separately in order to determine their progressive wear rates and to predict imminent tool failure. The results of this study clearly show that signals associated with each flute can be effectively segmented using the proposed flute tracking system. Furthermore, the results illustrate that by segmenting the sensor signal by flutes it is possible to investigate the wear in each physical cutting edge of the cutting tool. These findings are significant in that they facilitate the online condition monitoring of a cutting tool for each specific flute without the need for operators/engineers to perform manual inspections of the tool.

Keywords: machining, milling operation, tool condition monitoring, tool wear prediction

Procedia PDF Downloads 299
280 Ethnography of the Social and Cultural Perspectives of Childhood Neuro-Developmental Disorders: Implications for Health Seeking

Authors: Denis Nono, Catherine Abbo, Thomas Wenzel

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Introduction: The study explored socio-cultural perspectives of childhood disorders and its implications for health seeking. Emphasis was on exploring local understanding and perceptions and how these ideas affect health seeking. Study aim: To explore the socio-cultural perspectives of neuro-developmental disorders and its implications on health seeking behaviour. Methods: The methods used in this study included key informant interviews conducted with health professionals. Parents of the children aged (6-15 years) with neuro-developmental disorders were recruited from the hospital to participate in focus group discussion, participant observation and individual in-depth interviews. Results: The study found out that stigma extended from children to parents and caregivers who were also shunned by community members. Participants described their children as “a gift from God” others described them as “a test from God”. The communities perceive the disorders as a spiritual infliction and always insisted that the children be taken for Acholi cultural and traditional rituals to cleanse children and they believed that mental illness has spiritual linkages. Conclusion: This study gives unique insights into the perceptions of neuro-developmental disorders and health seeking behavior in Gulu District and neighboring communities. The results showed that communities linked disorders to spiritual affliction, misunderstandings between families, bewitching, and other supernatural forces. Some of the participants highly recommended biomedical approaches to prevention, management and control of the disorders.

Keywords: ethnography, health seeking, neuro-developmental disorders, socio-cultural

Procedia PDF Downloads 137
279 The Effect of Mathematical Modeling of Damping on the Seismic Energy Demands

Authors: Selamawit Dires, Solomon Tesfamariam, Thomas Tannert

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Modern earthquake engineering and design encompass performance-based design philosophy. The main objective in performance-based design is to achieve a system performing precisely to meet the design objectives so to reduce unintended seismic risks and associated losses. Energy-based earthquake-resistant design is one of the design methodologies that can be implemented in performance-based earthquake engineering. In energy-based design, the seismic demand is usually described as the ratio of the hysteretic to input energy. Once the hysteretic energy is known as a percentage of the input energy, it is distributed among energy-dissipating components of a structure. The hysteretic to input energy ratio is highly dependent on the inherent damping of a structural system. In numerical analysis, damping can be modeled as stiffness-proportional, mass-proportional, or a linear combination of stiffness and mass. In this study, the effect of mathematical modeling of damping on the estimation of seismic energy demands is investigated by considering elastic-perfectly-plastic single-degree-of-freedom systems representing short to long period structures. Furthermore, the seismicity of Vancouver, Canada, is used in the nonlinear time history analysis. According to the preliminary results, the input energy demand is not sensitive to the type of damping models deployed. Hence, consistent results are achieved regardless of the damping models utilized in the numerical analyses. On the other hand, the hysteretic to input energy ratios vary significantly for the different damping models.

Keywords: damping, energy-based seismic design, hysteretic energy, input energy

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278 Propranalol is Not Effective in Preventing the Progression to Severe Portal Hypertensive Gastropathy in Cirrhotic Patients who Had Undergone Variceal Eradication: A Randomised Controlled Trial

Authors: Jeffey George, Varghese Thomas

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Background and Objectives: PHG is an important source of gastrointestinal bleeding in patients with portal hypertension. Aim: To assess the progression to severe portal hypertensive gastropathy(PHG) in patients with cirrhosis who were treated with maximum tolerated dose of propranalol, after variceal eradication to grade II or below. Methods: Cirrhotic patients(child A and B) presenting with upper gastrointestinal bleeding with endoscopic findings of mild or no PHG were followed up over 6 months after variceal eradication to assess the progression to severe PHG. Included patients were randomised to either maximum tolerated doses of propranalol (group A) or to no treatment (group B). Primary end point of the study were the development of gastrointestinal bleed, evidence of hepatic decompensation and death. Progression to severe PHG were compared between the two groups. Results: 56 patients (49 males) were enrolled (group A = 28, group B = 28). 8 patients were excluded from final analysis (gi bleed=5, encephalopathy=2,HCC=1 including 4 deaths).3 patients were lost to follow-up, and 1 developed intolerance to propranalol. Mean dose of propranalol used was 60 mg per day. Progression to severe PHG in the fundus over 6 months was 23.8% in group A versus 15.8 % in group B (p = 0.52). Severe PHG was noted in body in 14.3% in group A versus 21.1% in group B (p = 0.57). 23.8 % in group A had progression to severe PHG compared with 15.8 % in group B (p =0.52). There was no statistically significant difference in the progression of PHG between the two groups(p=0.43). Conclusion: In this short term study propranalol was found not to prevent the progression to severe portal hypertensive gastropathy in cirrhotic patients who had undergone endotherapy for esophageal varices.

Keywords: propranalol, portal hypertensive gastropathy, cirrhotic patients, gastroenterology

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277 A Survey of Online User Perspectives and Age Profile in an Undergraduate Fundamental Business Technology Course

Authors: Danielle Morin, Jennifer D. E. Thomas, Raafat G. Saade, Daniela Petrachi

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Over the past few decades, more and more students choose to enroll in online classes instead of attending in-class lectures. While past studies consider students’ attitudes towards online education and how their grades differed from in-class lectures, the profile of the online student remains a blur. To shed light on this, an online survey was administered to about 1,500 students enrolled in an undergraduate Fundamental Business Technology course at a Canadian University. The survey was comprised of questions on students’ demographics, their reasons for choosing online courses, their expectations towards the course, the communication channels they use for the course with fellow students and with the instructor. This paper focused on the research question: Do the perspectives of online students concerning the online experience, in general, and in the course in particular, differ according to age profile? After several statistical analyses, it was found that age does have an impact on the reasons why students select online classes instead of in-class. For example, it was found that the perception that an online course might be easier than in-class delivery was a more important reason for younger students than for older ones. Similarly, the influence of friends is much more important for younger students, than for older students. Similar results were found when analyzing students’ expectation about the online course and their use of communication tools. Overall, the age profile of online users had an impact on reasons, expectations and means of communication in an undergraduate Fundamental Business Technology course. It is left to be seen if this holds true across other courses, graduate and undergraduate.

Keywords: communication channels, fundamentals of business technology, online classes, pedagogy, user age profile, user perspectives

Procedia PDF Downloads 244
276 Ramadan as a Model of Intermittent Fasting: Effects on Gut Hormones, Appetite and Body Composition in Diabetes vs. Controls

Authors: Turki J. Alharbi, Jencia Wong, Dennis Yue, Tania P. Markovic, Julie Hetherington, Ted Wu, Belinda Brooks, Radhika Seimon, Alice Gibson, Stephanie L. Silviera, Amanda Sainsbury, Tanya J. Little

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Fasting has been practiced for centuries and is incorporated into the practices of different religions including Islam, whose followers intermittently fast throughout the month of Ramadan. Thus, Ramadan presents a unique model of prolonged intermittent fasting (IF). Despite a growing body of evidence for a cardio-metabolic and endocrine benefit of IF, detailed studies of the effects of IF on these indices in type 2 diabetes are scarce. We studied 5 subjects with type 2 diabetes (T2DM) and 7 healthy controls (C) at baseline (pre), and in the last week of Ramadan (post). Fasting circulating levels of glucose, HbA1c and lipids, as well as body composition (with DXA) and resting energy expenditure (REE) were measured. Plasma gut hormone levels and appetite responses to a mixed meal were also studied. Data are means±SEM. Ramadan decreased total fat mass (-907±92 g, p=0.001) and trunk fat (-778±190 g, p=0.014) in T2DM but not in controls, without any reductions in lean mass or REE. There was a trend towards a decline in plasma FFA in both groups. Ramadan had no effect on body weight, glycemia, blood pressure, or plasma lipids in either group. In T2DM only, the area under the curve for post-meal plasma ghrelin concentrations increased after Ramadan (pre:6632±1737 vs. post:9025±2518 pg/ml.min-1, p=0.045). Despite this increase in orexigenic ghrelin, subjective appetite scores were not altered by Ramadan. Meal-induced plasma concentrations of the satiety hormone pancreatic polypeptide did not change during Ramadan, but were higher in T2DM compared to controls (post: C: 23486±6677 vs. T2DM: 62193±6880 pg/ml.min-1, p=0.003. In conclusion, Ramadan, as a model for IF appears to have more favourable effects on body composition in T2DM, without adverse effects on metabolic control or subjective appetite. These data suggest that IF may be particularly beneficial in T2DM as a nutritional intervention. Larger studies are warranted.

Keywords: type 2 diabetes, obesity, intermittent fasting, appetite regulating hormones

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275 Fabrication and Analysis of Simplified Dragonfly Wing Structures Created Using Balsa Wood and Red Prepreg Fibre Glass for Use in Biomimetic Micro Air Vehicles

Authors: Praveena Nair Sivasankaran, Thomas Arthur Ward, Rubentheren Viyapuri

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Paper describes a methodology to fabricate a simplified dragonfly wing structure using balsa wood and red prepreg fibre glass. These simplified wing structures were created for use in Biomimetic Micro Air Vehicles (BMAV). Dragonfly wings are highly corrugated and possess complex vein structures. In order to mimic the wings function and retain its properties, a simplified version of the wing was designed. The simplified dragonfly wing structure was created using a method called spatial network analysis which utilizes Canny edge detection method. The vein structure of the wings were carved out in balsa wood and red prepreg fibre glass. Balsa wood and red prepreg fibre glass was chosen due to its ultra- lightweight property and hence, highly suitable to be used in our application. The fabricated structure was then immersed in a nanocomposite solution containing chitosan as a film matrix, reinforced with chitin nanowhiskers and tannic acid as a crosslinking agent. These materials closely mimic the membrane of a dragonfly wing. Finally, the wings were subjected to a bending test and comparisons were made with previous research for verification. The results had a margin of difference of about 3% and thus the structure was validated.

Keywords: dragonfly wings, simplified, Canny edge detection, balsa wood, red prepreg, chitin, chitosan, tannic acid

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274 Assessment of Knowledge and Attitude towards End of Life Care among Nurses Working in Tertiary Hospital

Authors: Emni Omar Daw Hussin, Pathmawathi Subramanian, Wong Li Ping

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Background: To provide quality care at the end of life, nurses should possess knowledge and skills to provide effective end-of-life care, as well as develop the attitudes and interpersonal competence to provide compassionate care. Aim: This study aimed to assess nurses’ knowledge and attitude towards end of life care and caring for terminal ill patients and to examine relationships among demographic variables and nurse’s knowledge and attitudes toward end of life care and caring for terminal ill patients. Method: a cross-sectional study was conducted at 1 tertiary hospital located in Kuala Lumpur, Malaysia. Self-administrative questionnaire was used to collect data from 553 nurses from over all departments except emergency department, operation theater and outpatient clinic. Two tools were used in this study, the Frommelt’s Attitude Toward Care of the Dying (FATCOD) Scale to assess the nurses’ attitude and End of Life Knowledge Assessment to assess the nurses’ knowledge. Result: the result of this study yielded that, the majority of participants (54.8%) and (54.4%) have less positive attitude and knowledge towards end of life care and caring for terminal ill patients respectively. As well as there is no significant relationship were found between nurses’ ethnicity, religion, and the total score of FATCOD scale; End of Life Knowledge Assessment score. On other hand there is significant relationship among nurses’ age, working experience, level of education, attending any post basic courses and the total score of both FATCOD scale and End of Life Knowledge Assessment. Conclusion: A lack of education and experience and post basic course about end of life care and palliative care may contribute to the negative attitudes and poor knowledge regarding end of life care. Providing sufficient courses about end of life care could enhance the nurses’ knowledge towards end of life care, as well as providing a reflective narrative environment in which nurses can express their personal feelings about death and dying could be a potentially effective approach. Implication for Practice: This study elaborates the need for further research to develop an effective educational programs to enhance nurses’ knowledge and to promote positive attitude towards death and dying, as well as enhance communication skills, and coping strategies.

Keywords: knowledge, attitude, nurse, end of life care

Procedia PDF Downloads 439
273 Radio Frequency Identification Device Based Emergency Department Critical Care Billing: A Framework for Actionable Intelligence

Authors: Shivaram P. Arunachalam, Mustafa Y. Sir, Andy Boggust, David M. Nestler, Thomas R. Hellmich, Kalyan S. Pasupathy

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Emergency departments (EDs) provide urgent care to patients throughout the day in a complex and chaotic environment. Real-time location systems (RTLS) are increasingly being utilized in healthcare settings, and have shown to improve safety, reduce cost, and increase patient satisfaction. Radio Frequency Identification Device (RFID) data in an ED has been shown to compute variables such as patient-provider contact time, which is associated with patient outcomes such as 30-day hospitalization. These variables can provide avenues for improving ED operational efficiency. A major challenge with ED financial operations is under-coding of critical care services due to physicians’ difficulty reporting accurate times for critical care provided under Current Procedural Terminology (CPT) codes 99291 and 99292. In this work, the authors propose a framework to optimize ED critical care billing using RFID data. RFID estimated physician-patient contact times could accurately quantify direct critical care services which will help model a data-driven approach for ED critical care billing. This paper will describe the framework and provide insights into opportunities to prevent under coding as well as over coding to avoid insurance audits. Future work will focus on data analytics to demonstrate the feasibility of the framework described.

Keywords: critical care billing, CPT codes, emergency department, RFID

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272 Validation of the X-Ray Densitometry Method for Radial Density Pattern Determination of Acacia seyal var. seyal Tree Species

Authors: Hanadi Mohamed Shawgi Gamal, Claus Thomas Bues

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Wood density is a variable influencing many of the technological and quality properties of wood. Understanding the pattern of wood density radial variation is important for its end-use. The X-ray technique, traditionally applied to softwood species to assess the wood quality properties, due to its simple and relatively uniform wood structure. On the other hand, very limited information is available about the validation of using this technique for hardwood species. The suitability of using the X-ray technique for the determination of hardwood density has a special significance in countries like Sudan, where only a few timbers are well known. This will not only save the time consumed by using the traditional methods, but it will also enhance the investigations of the great number of the lesser known species, the thing which will fill the huge cap of lake information of hardwood species growing in Sudan. The current study aimed to evaluate the validation of using the X-ray densitometry technique to determine the radial variation of wood density of Acacia seyal var. seyal. To this, a total of thirty trees were collected randomly from four states in Sudan. The wood density radial trend was determined using the basic density as well as density obtained by the X-ray densitometry method in order to assess the validation of X-ray technique in wood density radial variation determination. The results showed that the pattern of radial trend of density obtained by X-ray technique is very similar to that achieved by basic density. These results confirmed the validation of using the X-ray technique for Acacia seyal var. seyal density radial trend determination. It also promotes the suitability of using this method in other hardwood species.

Keywords: x-ray densitometry, wood density, Acacia seyal var. seyal, radial variation

Procedia PDF Downloads 147
271 Developing a Framework to Aid Sustainable Assessment in Indian Buildings

Authors: P. Amarnath, Albert Thomas

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Buildings qualify to be the major consumer of energy and resources thereby urging the designers, architects and policy makers to place a great deal of effort in achieving and implementing sustainable building strategies in construction. Green building rating systems help a great deal in this by measuring the effectiveness of these strategies along with the escalation of building performance in social, environmental and economic perspective, and construct new sustainable buildings. However, for a country like India, enormous population and its rapid rate of growth impose an increasing burden on the country's limited and continuously degrading natural resource base, which also includes the land available for construction. In general, the number of sustainable rated buildings in India is very minimal primarily due to the complexity and obstinate nature of the assessment systems/regulations that restrict the stakeholders and designers in proper implementation and utilization of these rating systems. This paper aims to introduce a data driven and user-friendly framework which cross compares the present prominent green building rating systems such as LEED, BREEAM, and GRIHA and subsequently help the users to rate their proposed building design as per the regulations of these assessment frameworks. This framework is validated using the input data collected from green buildings constructed globally. The proposed system has prospects to encourage the users to test the efficiency of various sustainable construction practices and thereby promote more sustainable buildings in the country.

Keywords: BREEAM, GRIHA, green building rating systems, LEED, sustainable buildings

Procedia PDF Downloads 132
270 Applicability of Overhangs for Energy Saving in Existing High-Rise Housing in Different Climates

Authors: Qiong He, S. Thomas Ng

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Upgrading the thermal performance of building envelope of existing residential buildings is an effective way to reduce heat gain or heat loss. Overhang device is a common solution for building envelope improvement as it can cut down solar heat gain and thereby can reduce the energy used for space cooling in summer time. Despite that, overhang can increase the demand for indoor heating in winter due to its function of lowering the solar heat gain. Obviously, overhang has different impacts on energy use in different climatic zones which have different energy demand. To evaluate the impact of overhang device on building energy performance under different climates of China, an energy analysis model is built up in a computer-based simulation program known as DesignBuilder based on the data of a typical high-rise residential building. The energy simulation results show that single overhang is able to cut down around 5% of the energy consumption of the case building in the stand-alone situation or about 2% when the building is surrounded by other buildings in regions which predominantly rely on space cooling though it has no contribution to energy reduction in cold region. In regions with cold summer and cold winter, adding overhang over windows can cut down around 4% and 1.8% energy use with and without adjoining buildings, respectively. The results indicate that overhang might not an effective shading device to reduce the energy consumption in the mixed climate or cold regions.

Keywords: overhang, energy analysis, computer-based simulation, design builder, high-rise residential building, climate, BIM model

Procedia PDF Downloads 356
269 Development of Immersive Virtual Reality System for Planning of Cargo Loading Operations

Authors: Eugene Y. C. Wong, Daniel Y. W. Mo, Cosmo T. Y. Ng, Jessica K. Y. Chan, Leith K. Y. Chan, Henry Y. K. Lau

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The real-time planning visualisation, precise allocation and loading optimisation in air cargo load planning operations are increasingly important as more considerations are needed on dangerous cargo loading, locations of lithium batteries, weight declaration and limited aircraft capacity. The planning of the unit load devices (ULD) can often be carried out only in a limited number of hours before flight departure. A dynamic air cargo load planning system is proposed with the optimisation of cargo load plan and visualisation of planning results in virtual reality systems. The system aims to optimise the cargo load planning and visualise the simulated loading planning decision on air cargo terminal operations. Adopting simulation tools, Cave Automatic Virtual Environment (CAVE) and virtual reality technologies, the results of planning with reference to weight and balance, Unit Load Device (ULD) dimensions, gateway, cargo nature and aircraft capacity are optimised and presented. The virtual reality system facilities planning, operations, education and training. Staff in terminals are usually trained in a traditional push-approach demonstration with enormous manual paperwork. With the support of newly customized immersive visualization environment, users can master the complex air cargo load planning techniques in a problem based training with the instant result being immersively visualised. The virtual reality system is developed with three-dimensional (3D) projectors, screens, workstations, truss system, 3D glasses, and demonstration platform and software. The content will be focused on the cargo planning and loading operations in an air cargo terminal. The system can assist decision-making process during cargo load planning in the complex operations of air cargo terminal operations. The processes of cargo loading, cargo build-up, security screening, and system monitoring can be further visualised. Scenarios are designed to support and demonstrate the daily operations of the air cargo terminal, including dangerous goods, pets and animals, and some special cargos.

Keywords: air cargo load planning, optimisation, virtual reality, weight and balance, unit load device

Procedia PDF Downloads 341
268 Reinforcement Learning for Robust Missile Autopilot Design: TRPO Enhanced by Schedule Experience Replay

Authors: Bernardo Cortez, Florian Peter, Thomas Lausenhammer, Paulo Oliveira

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Designing missiles’ autopilot controllers have been a complex task, given the extensive flight envelope and the nonlinear flight dynamics. A solution that can excel both in nominal performance and in robustness to uncertainties is still to be found. While Control Theory often debouches into parameters’ scheduling procedures, Reinforcement Learning has presented interesting results in ever more complex tasks, going from videogames to robotic tasks with continuous action domains. However, it still lacks clearer insights on how to find adequate reward functions and exploration strategies. To the best of our knowledge, this work is a pioneer in proposing Reinforcement Learning as a framework for flight control. In fact, it aims at training a model-free agent that can control the longitudinal non-linear flight dynamics of a missile, achieving the target performance and robustness to uncertainties. To that end, under TRPO’s methodology, the collected experience is augmented according to HER, stored in a replay buffer and sampled according to its significance. Not only does this work enhance the concept of prioritized experience replay into BPER, but it also reformulates HER, activating them both only when the training progress converges to suboptimal policies, in what is proposed as the SER methodology. The results show that it is possible both to achieve the target performance and to improve the agent’s robustness to uncertainties (with low damage on nominal performance) by further training it in non-nominal environments, therefore validating the proposed approach and encouraging future research in this field.

Keywords: Reinforcement Learning, flight control, HER, missile autopilot, TRPO

Procedia PDF Downloads 260
267 Investigation and Estimation of State of Health of Battery Pack in Battery Electric Vehicles-Online Battery Characterization

Authors: Ali Mashayekh, Mahdiye Khorasani, Thomas Weyh

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The tendency to use the Battery-Electric vehicle (BEV) for the low and medium driving range or even high driving range has been growing more and more. As a result, higher safety, reliability, and durability of the battery pack as a component of electric vehicles, which has a great share of cost and weight of the final product, are the topics to be considered and investigated. Battery aging can be considered as the predominant factor regarding the reliability and durability of BEV. To better understand the aging process, offline battery characterization has been widely used, which is time-consuming and needs very expensive infrastructures. This paper presents the substitute method for the conventional battery characterization methods, which is based on battery Modular Multilevel Management (BM3). According to this Topology, the battery cells can be drained and charged concerning their capacity, which allows varying battery pack structures. Due to the integration of the power electronics, the output voltage of the battery pack is no longer fixed but can be dynamically adjusted in small steps. In other words, each cell can have three different states, namely series, parallel, and bypass in connection with the neighbor cells. With the help of MATLAB/Simulink and by using the BM3 modules, the battery string model is created. This model allows us to switch two cells with the different SoC as parallel, which results in the internal balancing of the cells. But if the parallel switching lasts just for a couple of ms, we can have a perturbation pulse which can stimulate the cells out of the relaxation phase. With the help of modeling the voltage response pulse of the battery, it would be possible to characterize the cell. The Online EIS method, which is discussed in this paper, can be a robust substitute for the conventional battery characterization methods.

Keywords: battery characterization, SoH estimation, RLS, BEV

Procedia PDF Downloads 147
266 Localized Variabilities in Traffic-related Air Pollutant Concentrations Revealed Using Compact Sensor Networks

Authors: Eric A. Morris, Xia Liu, Yee Ka Wong, Greg J. Evans, Jeff R. Brook

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Air quality monitoring stations tend to be widely distributed and are often located far from major roadways, thus, determining where, when, and which traffic-related air pollutants (TRAPs) have the greatest impact on public health becomes a matter of extrapolation. Compact, multipollutant sensor systems are an effective solution as they enable several TRAPs to be monitored in a geospatially dense network, thus filling in the gaps between conventional monitoring stations. This work describes two applications of one such system named AirSENCE for gathering actionable air quality data relevant to smart city infrastructures. In the first application, four AirSENCE devices were co-located with traffic monitors around the perimeter of a city block in Oshawa, Ontario. This study, which coincided with the COVID-19 outbreak of 2020 and subsequent lockdown measures, demonstrated a direct relationship between decreased traffic volumes and TRAP concentrations. Conversely, road construction was observed to cause elevated TRAP levels while reducing traffic volumes, illustrating that conventional smart city sensors such as traffic counters provide inadequate data for inferring air quality conditions. The second application used two AirSENCE sensors on opposite sides of a major 2-way commuter road in Toronto. Clear correlations of TRAP concentrations with wind direction were observed, which shows that impacted areas are not necessarily static and may exhibit high day-to-day variability in air quality conditions despite consistent traffic volumes. Both of these applications provide compelling evidence favouring the inclusion of air quality sensors in current and future smart city infrastructure planning. Such sensors provide direct measurements that are useful for public health alerting as well as decision-making for projects involving traffic mitigation, heavy construction, and urban renewal efforts.

Keywords: distributed sensor network, continuous ambient air quality monitoring, Smart city sensors, Internet of Things, traffic-related air pollutants

Procedia PDF Downloads 69
265 Development of Internet of Things (IoT) with Mobile Voice Picking and Cargo Tracing Systems in Warehouse Operations of Third-Party Logistics

Authors: Eugene Y. C. Wong

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The increased market competition, customer expectation, and warehouse operating cost in third-party logistics have motivated the continuous exploration in improving operation efficiency in warehouse logistics. Cargo tracing in ordering picking process consumes excessive time for warehouse operators when handling enormous quantities of goods flowing through the warehouse each day. Internet of Things (IoT) with mobile cargo tracing apps and database management systems are developed this research to facilitate and reduce the cargo tracing time in order picking process of a third-party logistics firm. An operation review is carried out in the firm with opportunities for improvement being identified, including inaccurate inventory record in warehouse management system, excessive tracing time on stored products, and product misdelivery. The facility layout has been improved by modifying the designated locations of various types of products. The relationship among the pick and pack processing time, cargo tracing time, delivery accuracy, inventory turnover, and inventory count operation time in the warehouse are evaluated. The correlation of the factors affecting the overall cycle time is analysed. A mobile app is developed with the use of MIT App Inventor and the Access management database to facilitate cargo tracking anytime anywhere. The information flow framework from warehouse database system to cloud computing document-sharing, and further to the mobile app device is developed. The improved performance on cargo tracing in the order processing cycle time of warehouse operators have been collected and evaluated. The developed mobile voice picking and tracking systems brings significant benefit to the third-party logistics firm, including eliminating unnecessary cargo tracing time in order picking process and reducing warehouse operators overtime cost. The mobile tracking device is further planned to enhance the picking time and cycle count of warehouse operators with voice picking system in the developed mobile apps as future development.

Keywords: warehouse, order picking process, cargo tracing, mobile app, third-party logistics

Procedia PDF Downloads 368
264 Occupational Health Services (OHS) in Hong Kong Hospitals and the Experience of Nurses: A Mixed Methods Study

Authors: Wong Yat Cheung Maggie

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Occupational Safety and Health Ordinance (OS&HO) (Chap 509) was enacted in 1997, OHS in HK should be growing and maturing, with a holistic approach to occupational health and safety in the workplace including physical, mental, social and spiritual well-being. The question is “How effective are OHSPs in meeting the current needs of HK health workers?” This study was designed to explore the issue for the first time, to empirically analyse the views of those who work in the system. The study employed a mixed method approach to collect various data from Occupational Health Service Providers (OHSPs), Occupational Health Service Consumers (OHSC): Registered nurses working in the hospital setting. This study was designed in two phases and two stages. Phase I Stage I was a paper survey to collect the data on OHSP. Then Phase I Stage II was a follow-up interview. Phase II Stage I was a paper survey to collect the data on OHSC. Then Phase II Stage II was a follow-up focus group study on OHSC for further clarification of the Phase II and Stage I result. The Phase I result reflects HK OHSPs point of view and their experience in the existing OHS practice in the local hospitals. It reflects various styles of reporting systems, staff profiles background and resource in providing OHS in HK hospitals. However, the basic OHS concern is similar between hospitals. In general, the OHS policies and procedures are available on site even though they may have different foci. The Phase II result is reflecting the HKs OHSCs echoes the OHSP feedback at providing of OHS, OHS concern and related policies and procedure are available on site. However, the most significant feedback from the OHSC at Phase II Stage II shows, nurses experienced various OHS concern most commonly work stress, workplace harassment and back strain without formal or official report to the related parties. The lack of reporting was due to the management handling attitude, stakeholders’ compliance and term of definition still have room to be improved even the related policies and procedures are available on site.

Keywords: occupational health service, registered nurse, Hong Kong hospital, mixed method

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263 A Human Centered Design of an Exoskeleton Using Multibody Simulation

Authors: Sebastian Kölbl, Thomas Reitmaier, Mathias Hartmann

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Trial and error approaches to adapt wearable support structures to human physiology are time consuming and elaborate. However, during preliminary design, the focus lies on understanding the interaction between exoskeleton and the human body in terms of forces and moments, namely body mechanics. For the study at hand, a multi-body simulation approach has been enhanced to evaluate actual forces and moments in a human dummy model with and without a digital mock-up of an active exoskeleton. Therefore, different motion data have been gathered and processed to perform a musculosceletal analysis. The motion data are ground reaction forces, electromyography data (EMG) and human motion data recorded with a marker-based motion capture system. Based on the experimental data, the response of the human dummy model has been calibrated. Subsequently, the scalable human dummy model, in conjunction with the motion data, is connected with the exoskeleton structure. The results of the human-machine interaction (HMI) simulation platform are in particular resulting contact forces and human joint forces to compare with admissible values with regard to the human physiology. Furthermore, it provides feedback for the sizing of the exoskeleton structure in terms of resulting interface forces (stress justification) and the effect of its compliance. A stepwise approach for the setup and validation of the modeling strategy is presented and the potential for a more time and cost-effective development of wearable support structures is outlined.

Keywords: assistive devices, ergonomic design, inverse dynamics, inverse kinematics, multibody simulation

Procedia PDF Downloads 157
262 Stability Optimization of NABH₄ via PH and H₂O:NABH₄ Ratios for Large Scale Hydrogen Production

Authors: Parth Mehta, Vedasri Bai Khavala, Prabhu Rajagopal, Tiju Thomas

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There is an increasing need for alternative clean fuels, and hydrogen (H₂) has long been considered a promising solution with a high calorific value (142MJ/kg). However, the storage of H₂ and expensive processes for its generation have hindered its usage. Sodium borohydride (NaBH₄) can potentially be used as an economically viable means of H₂ storage. Thus far, there have been attempts to optimize the life of NaBH₄ (half-life) in aqueous media by stabilizing it with sodium hydroxide (NaOH) for various pH values. Other reports have shown that H₂ yield and reaction kinetics remained constant for all ratios of H₂O to NaBH₄ > 30:1, without any acidic catalysts. Here we highlight the importance of pH and H₂O: NaBH₄ ratio (80:1, 40:1, 20:1 and 10:1 by weight), for NaBH₄ stabilization (half-life reaction time at room temperature) and corrosion minimization of H₂ reactor components. It is interesting to observe that at any particular pH>10 (e.g., pH = 10, 11 and 12), the H₂O: NaBH₄ ratio does not have the expected linear dependence with stability. On the contrary, high stability was observed at the ratio of 10:1 H₂O: NaBH₄ across all pH>10. When the H₂O: NaBH₄ ratio is increased from 10:1 to 20:1 and beyond (till 80:1), constant stability (% degradation) is observed with respect to time. For practical usage (consumption within 6 hours of making NaBH₄ solution), 15% degradation at pH 11 and NaBH₄: H₂O ratio of 10:1 is recommended. Increasing this ratio demands higher NaOH concentration at the same pH, thus requiring a higher concentration or volume of acid (e.g., HCl) for H₂ generation. The reactions are done with tap water to render the results useful from an industrial standpoint. The observed stability regimes are rationalized based on complexes associated with NaBH₄ when solvated in water, which depend sensitively on both pH and NaBH₄: H₂O ratio.

Keywords: hydrogen, sodium borohydride, stability optimization, H₂O:NaBH₄ ratio

Procedia PDF Downloads 113