Search results for: principal component
865 Microbubbles Enhanced Synthetic Phorbol Ester Degradation by Ozonolysis
Authors: D. Kuvshinov, A. Siswanto, W. Zimmerman
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A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil can also be used as a food stock due to its significant nutrition content. The limitations for utilizing the oil as a food stock are mainly due to a toxicity of PE. Nowadays a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence. Ozone is considered as a strong oxidative agent. It reaction with PE it attacks the carbon double bond of PE. This modification of PE molecular structure results into nontoxic ester with high lipid content. This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is a simultaneous application of new microscale plasma unit for ozone production and patented gas oscillation technology. In combination with a reactor design the technology permits ozone injection to the water-TPA mixture in form of microbubbles. The efficacy of a heterogeneous process depends on diffusion coefficient which can be controlled by contact time and interface area. The low velocity of rising microbubbles and high surface to volume ratio allow fast mass transfer to be achieved during the process. Direct injection of ozone is the most efficient process for a highly reactive and short lived chemical. Data on the plasma unit behavior are presented and influence of the gas oscillation technology to the microbubbles production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown.Keywords: microbubble, ozonolysis, synthetic phorbol ester, chemical engineering
Procedia PDF Downloads 217864 Evolution of Bombings against Transportation Infrastructure
Authors: Jonathan K. Hill
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The transportation networks throughout Africa remain the only transportation infrastructure system in the world that is attacked by terrorists at a high frequency, so the international community can learn from each attack. The targeting of transportation should be recognized as a direct attack against a civilian population, so the international community should work to better understand the types of attacks utilized, the types of improvised explosive device designs adapted to transportation targets, and the ways the various modes of transportation have been attacked throughout the continent. Some countries have seen grenade attacks that have resulted in only injuries, while some countries have experienced large vehicle bombings that have resulted in hundreds of injuries and numerous deaths. With insurgencies, explosive devices have been small, complex, and generally target an enemy of the insurgency. With terrorist bombings, the explosive devices have been large, brazen, and targeted at civilian populations. And, these civilian populations are easily targeted within the transportation system. The presentation provided by Assess Africa LLC is titled ‘Evolution of Bombings Against Transportation Infrastructure’ and covers improvised explosive device characteristics, how improvised explosive devices have been adapted to transportation targets in Africa, analyses recent incidents, and provides some advice for effective protective measures. A main component of the improvised explosive device characteristics portion of the presentation focuses on the link between explosive device components, the intelligence network, and the bomb-builder’s network. By understanding the components, how the use of various components can be linked to a terrorist group’s capabilities, and how the bomb-builder acquires materials, the analysis of improvised explosive device attacks takes on a new direction – one that focuses on defeating the network instead of merely reviewing incidents of the past.Keywords: Africa, bombings, critical infrastructure protection, transportation security
Procedia PDF Downloads 425863 Evaluation of Rheological Properties, Anisotropic Shrinkage, and Heterogeneous Densification of Ceramic Materials during Liquid Phase Sintering by Numerical-Experimental Procedure
Authors: Hamed Yaghoubi, Esmaeil Salahi, Fateme Taati
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The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermomechanical characteristics of the material such as relative density, temperature, grain size, and diffusion coefficient and activation energy. The main goal of this research is to acquire a comprehensive understanding of the response of an incompressible viscose ceramic material during liquid phase sintering process such as stress-strain relations, sintering and hydrostatic stress, the prediction of anisotropic shrinkage and heterogeneous densification as a function of sintering time by including the simultaneous influence of gravity field, and frictional force. After raw materials analysis, the standard hard porcelain mixture as a ceramic body was designed and prepared. Three different experimental configurations were designed including midpoint deflection, sinter bending, and free sintering samples. The numerical method for the ceramic specimens during the liquid phase sintering process are implemented in the CREEP user subroutine code in ABAQUS. The numerical-experimental procedure shows the anisotropic behavior, the complete difference in spatial displacement through three directions, the incompressibility for ceramic samples during the sintering process. The anisotropic shrinkage factor has been proposed to investigate the shrinkage anisotropy. It has been shown that the shrinkage along the normal axis of casting sample is about 1.5 times larger than that of casting direction, the gravitational force in pyroplastic deformation intensifies the shrinkage anisotropy more than the free sintering sample. The lowest and greatest equivalent creep strain occurs at the intermediate zone and around the central line of the midpoint distorted sample, respectively. In the sinter bending test sample, the equivalent creep strain approaches to the maximum near the contact area with refractory support. The inhomogeneity in Von-Misses, pressure, and principal stress intensifies the relative density non-uniformity in all samples, except in free sintering one. The symmetrical distribution of stress around the center of free sintering sample, cause to hinder the pyroplastic deformations. Densification results confirmed that the effective bulk viscosity was well-defined with relative density values. The stress analysis confirmed that the sintering stress is more than the hydrostatic stress from start to end of sintering time so, from both theoretically and experimentally point of view, the sintering process occurs completely.Keywords: anisotropic shrinkage, ceramic material, liquid phase sintering process, rheological properties, numerical-experimental procedure
Procedia PDF Downloads 341862 Applying Biosensors’ Electromyography Signals through an Artificial Neural Network to Control a Small Unmanned Aerial Vehicle
Authors: Mylena McCoggle, Shyra Wilson, Andrea Rivera, Rocio Alba-Flores
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This work introduces the use of EMGs (electromyography) from muscle sensors to develop an Artificial Neural Network (ANN) for pattern recognition to control a small unmanned aerial vehicle. The objective of this endeavor exhibits interfacing drone applications beyond manual control directly. MyoWare Muscle sensor contains three EMG electrodes (dual and single type) used to collect signals from the posterior (extensor) and anterior (flexor) forearm and the bicep. Collection of raw voltages from each sensor were connected to an Arduino Uno and a data processing algorithm was developed with the purpose of interpreting the voltage signals given when performing flexing, resting, and motion of the arm. Each sensor collected eight values over a two-second period for the duration of one minute, per assessment. During each two-second interval, the movements were alternating between a resting reference class and an active motion class, resulting in controlling the motion of the drone with left and right movements. This paper further investigated adding up to three sensors to differentiate between hand gestures to control the principal motions of the drone (left, right, up, and land). The hand gestures chosen to execute these movements were: a resting position, a thumbs up, a hand swipe right motion, and a flexing position. The MATLAB software was utilized to collect, process, and analyze the signals from the sensors. The protocol (machine learning tool) was used to classify the hand gestures. To generate the input vector to the ANN, the mean, root means squared, and standard deviation was processed for every two-second interval of the hand gestures. The neuromuscular information was then trained using an artificial neural network with one hidden layer of 10 neurons to categorize the four targets, one for each hand gesture. Once the machine learning training was completed, the resulting network interpreted the processed inputs and returned the probabilities of each class. Based on the resultant probability of the application process, once an output was greater or equal to 80% of matching a specific target class, the drone would perform the motion expected. Afterward, each movement was sent from the computer to the drone through a Wi-Fi network connection. These procedures have been successfully tested and integrated into trial flights, where the drone has responded successfully in real-time to predefined command inputs with the machine learning algorithm through the MyoWare sensor interface. The full paper will describe in detail the database of the hand gestures, the details of the ANN architecture, and confusion matrices results.Keywords: artificial neural network, biosensors, electromyography, machine learning, MyoWare muscle sensors, Arduino
Procedia PDF Downloads 174861 ID + PD: Training Instructional Designers to Foster and Facilitate Learning Communities in Digital Spaces
Authors: Belkis L. Cabrera
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Contemporary technological innovations have reshaped possibility, interaction, communication, engagement, education, and training. Indeed, today, a high-quality technology enhanced learning experience can be transformative as much for the learner as for the educator-trainer. As innovative technologies continue to facilitate, support, foster, and enhance collaboration, problem-solving, creativity, adaptiveness, multidisciplinarity, and communication, the field of instructional design (ID) also continues to develop and expand. Shifting its focus from media to the systematic design of instruction, or rather from the gadgets and devices themselves to the theories, models, and impact of implementing educational technology, the evolution of ID marks a restructuring of the teaching, learning, and training paradigms. However, with all of its promise, this latter component of ID remains underdeveloped. The majority of ID models are crafted and guided by learning theories and, therefore, most models are constructed around student and educator roles rather than trainer roles. Thus, when these models or systems are employed for training purposes, they usually have to be re-fitted, tweaked, and stretched to meet the training needs. This paper is concerned with the training or professional development (PD) facet of instructional design and how ID models built on teacher-to-teacher interaction and dialogue can support the creation of professional learning communities (PLCs) or communities of practice (CoPs), which can augment learning and PD experiences for all. Just as technology is changing the face of education, so too can it change the face of PD within the educational realm. This paper not only provides a new ID model but using innovative technologies such as Padlet and Thinkbinder, this paper presents a concrete example of how a traditional body-to-body, brick, and mortar learning community can be transferred and transformed into the online context.Keywords: communities of practice, e-learning, educational reform, instructional design, professional development, professional learning communities, technology, training
Procedia PDF Downloads 340860 Space Telemetry Anomaly Detection Based On Statistical PCA Algorithm
Authors: Bassem Nassar, Wessam Hussein, Medhat Mokhtar
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The crucial concern of satellite operations is to ensure the health and safety of satellites. The worst case in this perspective is probably the loss of a mission but the more common interruption of satellite functionality can result in compromised mission objectives. All the data acquiring from the spacecraft are known as Telemetry (TM), which contains the wealth information related to the health of all its subsystems. Each single item of information is contained in a telemetry parameter, which represents a time-variant property (i.e. a status or a measurement) to be checked. As a consequence, there is a continuous improvement of TM monitoring systems in order to reduce the time required to respond to changes in a satellite's state of health. A fast conception of the current state of the satellite is thus very important in order to respond to occurring failures. Statistical multivariate latent techniques are one of the vital learning tools that are used to tackle the aforementioned problem coherently. Information extraction from such rich data sources using advanced statistical methodologies is a challenging task due to the massive volume of data. To solve this problem, in this paper, we present a proposed unsupervised learning algorithm based on Principle Component Analysis (PCA) technique. The algorithm is particularly applied on an actual remote sensing spacecraft. Data from the Attitude Determination and Control System (ADCS) was acquired under two operation conditions: normal and faulty states. The models were built and tested under these conditions and the results shows that the algorithm could successfully differentiate between these operations conditions. Furthermore, the algorithm provides competent information in prediction as well as adding more insight and physical interpretation to the ADCS operation.Keywords: space telemetry monitoring, multivariate analysis, PCA algorithm, space operations
Procedia PDF Downloads 415859 Catalytic Wet Air Oxidation as a Pretreatment Option for Biodegradability Enhancement of Industrial Effluent
Authors: Sushma Yadav, Anil K. Saroha
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Complex industrial effluent generated from chemical industry is contaminated with toxic and hazardous organic compounds and not amenable to direct biological treatment. To effectively remove many toxic organic pollutants has made it evident that new, compact and more efficient systems are needed. Catalytic Wet Air Oxidation (CWAO) is a promising treatment technology for the abatement of organic pollutants in wastewater. A lot of information is available on using CWAO for the treatment of synthetic solution containing single organic pollutant. But the real industrial effluents containing multi-component mixture of organic compounds were less studied. The main objective of this study is to use the CWAO process for converting the organics into compounds more amenable to biological treatment; complete oxidation may be too expensive. Therefore efforts were made in the present study to explore the potential of alumina based Platinum (Pt) catalyst for the treatment of industrial organic raffinate containing toxic constituents like ammoniacal nitrogen, pyridine etc. The catalysts were prepared by incipient wetness impregnation method and characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and BET (Brunauer, Emmett, and Teller) surface area. CWAO experiments were performed at atmospheric pressure and (30 °C - 70 °C) temperature conditions and the results were evaluated in terms of COD removal efficiency. The biodegradability test was performed by BOD/COD ratio for checking the toxicity of the industrial wastewater as well as for the treated water. The BOD/COD ratio of treated water was significantly increased and signified that the toxicity of the organics was decreased while the biodegradability was increased, indicating the more amenability towards biological treatment.Keywords: alumina based pt catalyst, BOD/COD ratio, catalytic wet air oxidation, COD removal efficiency, industrial organic raffinate
Procedia PDF Downloads 303858 Energy Consumption Estimation for Hybrid Marine Power Systems: Comparing Modeling Methodologies
Authors: Kamyar Maleki Bagherabadi, Torstein Aarseth Bø, Truls Flatberg, Olve Mo
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Hydrogen fuel cells and batteries are one of the promising solutions aligned with carbon emission reduction goals for the marine sector. However, the higher installation and operation costs of hydrogen-based systems compared to conventional diesel gensets raise questions about the appropriate hydrogen tank size, energy, and fuel consumption estimations. Ship designers need methodologies and tools to calculate energy and fuel consumption for different component sizes to facilitate decision-making regarding feasibility and performance for retrofits and design cases. The aim of this work is to compare three alternative modeling approaches for the estimation of energy and fuel consumption with various hydrogen tank sizes, battery capacities, and load-sharing strategies. A fishery vessel is selected as an example, using logged load demand data over a year of operations. The modeled power system consists of a PEM fuel cell, a diesel genset, and a battery. The methodologies used are: first, an energy-based model; second, considering load variations during the time domain with a rule-based Power Management System (PMS); and third, a load variations model and dynamic PMS strategy based on optimization with perfect foresight. The errors and potentials of the methods are discussed, and design sensitivity studies for this case are conducted. The results show that the energy-based method can estimate fuel and energy consumption with acceptable accuracy. However, models that consider time variation of the load provide more realistic estimations of energy and fuel consumption regarding hydrogen tank and battery size, still within low computational time.Keywords: fuel cell, battery, hydrogen, hybrid power system, power management system
Procedia PDF Downloads 36857 The Impact of Corporate Finance on Financial Stability in the Western Balkan Countries
Authors: Luan Vardari, Dena Arapi-Vardari
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Financial stability is a critical component of economic growth and development, and it has been recognized as a key policy objective in many countries around the world. In the Western Balkans, financial stability has been a key issue in recent years, with a number of challenges facing the region, including high levels of public debt, weak banking systems, and economic volatility. Corporate finance, which refers to the financial management practices of firms, is an important factor that can impact financial stability. This paper aims to investigate corporate finance's impact on financial stability in Western Balkan countries. This study will use a mixed-methods approach to investigate the impact of corporate finance on financial stability in the Western Balkans. The study will begin with a comprehensive review of the existing literature on corporate finance and financial stability, focusing on the Western Balkan region. This will be followed by an empirical analysis of regional corporate finance practices using data from various industries and firms. The analysis will explore the relationship between corporate finance practices and financial stability, taking into account factors such as regulatory frameworks, economic conditions, and firm size. The results of the study are expected to provide insights into the impact of corporate finance on financial stability in the Western Balkans. Specifically, the study will identify the key corporate finance practices that contribute to financial stability in the region, as well as the challenges and obstacles that firms face in implementing effective corporate finance strategies. The study will also provide recommendations for policymakers and firms looking to enhance financial stability and resilience in the region.Keywords: financial regulation, debt management, investment decisions, dividend policies, economic volatility, banking systems, public debt, prudent financial management, firm size, policy recommendations
Procedia PDF Downloads 75856 The Photovoltaic Panel at End of Life: Experimental Study of Metals Release
Authors: M. Tammaro, S. Manzo, J. Rimauro, A. Salluzzo, S. Schiavo
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The solar photovoltaic (PV) modules are considered to have a negligible environmental impact compared to the fossil energy. Therefore also the waste management and the corresponding potential environmental hazard needs to be considered. The case of the photovoltaic panel is unique because the time lag from the manufacturing to the decommissioning as waste usually takes 25-30 years. Then the environmental hazard associated with end life of PV panels has been largely related to their metal contents. The principal concern regards the presence of heavy metals as Cd in thin film (TF) modules or Pb and Cr in crystalline silicon (c-Si) panels. At the end of life of PV panels, these dangerous substances could be released in the environment, if special requirements for their disposal are not adopted. Nevertheless, in literature, only a few experimental study about metal emissions from silicon crystalline/thin film panels and the corresponding environmental effect are present. As part of a study funded by the Italian national consortium for the waste collection and recycling (COBAT), the present work was aimed to analyze experimentally the potential release into the environment of hazardous elements, particularly metals, from PV waste. In this paper, for the first time, eighteen releasable metals a large number of photovoltaic panels, by c-Si and TF, manufactured in the last 30 years, together with the environmental effects by a battery of ecotoxicological tests, were investigated. Leaching tests are conducted on the crushed samples of PV module. The test is conducted according to Italian and European Standard procedure for hazard assessment of the granular waste and of the sludge. The sample material is shaken for 24 hours in HDPE bottles with an overhead mixer Rotax 6.8 VELP at indoor temperature and using pure water (18 MΩ resistivity) as leaching solution. The liquid-to-solid ratio was 10 (L/S=10, i.e. 10 liters of water per kg of solid). The ecotoxicological tests were performed in the subsequent 24 hours. A battery of toxicity test with bacteria (Vibrio fisheri), algae (Pseudochirneriella subcapitata) and crustacea (Daphnia magna) was carried out on PV panel leachates obtained as previously described and immediately stored in dark and at 4°C until testing (in the next 24 hours). For understand the actual pollution load, a comparison with the current European and Italian benchmark limits was performed. The trend of leachable metal amount from panels in relation to manufacturing years was then highlighted in order to assess the environmental sustainability of PV technology over time. The experimental results were very heterogeneous and show that the photovoltaic panels could represent an environmental hazard. The experimental results showed that the amounts of some hazardous metals (Pb, Cr, Cd, Ni), for c-Si and TF, exceed the law limits and they are a clear indication of the potential environmental risk of photovoltaic panels "as a waste" without a proper management.Keywords: photovoltaic panel, environment, ecotoxicity, metals emission
Procedia PDF Downloads 260855 Anaerobic Soil Disinfestation: Feasible Alternative to Soil Chemical Fumigants
Authors: P. Serrano-Pérez, M. C. Rodríguez-Molina, C. Palo, E. Palo, A. Lacasa
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Phytophthora nicotianae is the principal causal agent of root and crown rot disease of red pepper plants in Extremadura (Western Spain). There is a need to develop a biologically-based method of soil disinfestation that facilitates profitable and sustainable production without the use of chemical fumigants. Anaerobic Soil Disinfestation (ASD), as well know as biodisinfestation, has been shown to control a wide range of soil-borne pathogens and nematodes in numerous crop production systems. This method implies soil wetting, incorporation of a easily decomposable carbon-rich organic amendment and covering with plastic film for several weeks. ASD with rapeseed cake (var. Tocatta, a glucosinolates-free variety) used as C-source was assayed in spring 2014, before the pepper crop establishment. The field experiment was conducted at the Agricultural Research Centre Finca La Orden (Southwestern Spain) and the treatments were: rapeseed cake (RCP); rapeseed cake without plastic cover (RC); control non-amendment (CP) and control non-amendment without plastic cover (C). The experimental design was a randomized complete block design with four replicates and a plot size of 5 x 5 m. On 26 March, rapeseed cake (1 kg·m-2) was incorporated into the soil with a rotovator. Biological probes with the inoculum were buried at 15 and 30-cm depth (biological probes were previously prepared with 100 g of disinfected soil inoculated with chlamydospores (chlam) of P. nicotianae P13 isolate [100 chlam·g-1 of soil] and wrapped in agryl cloth). Sprinkler irrigation was run until field capacity and the corresponding plots were covered with transparent plastic (PE 0.05 mm). On 6 May plastics were removed, the biological probes were dug out and a bioassay was established. One pepper seedling at the 2 to 4 true-leaves stage was transplanted in the soil from each biological probe. Plants were grown in a climatic chamber and disease symptoms were recorded every week during 2 months. Fragments of roots and crown of symptomatic plants were analyzed on NARPH media and soil from rizospheres was analyzed using carnation petals as baits. Results of “survival” were expressed as the percentage of soil samples where P. nicotianae was detected and results of “infectivity” were expressed as the percentage of diseased plants. No differences were detected in deep effect. Infectivity of P. nicotianae chlamydospores was successfully reduced in RCP treatment (4.2% of infectivity) compared with the controls (41.7% of infectivity). The pattern of survival was similar to infectivity observed by the bioassay: 21% of survival in RCP; 79% in CP; 83% in C and 87% in RC. Although ASD may be an effective alternative to chemical fumigants to pest management, more research is necessary to show their impact on the microbial community and chemistry of the soil.Keywords: biodisinfestation, BSD, soil fumigant alternatives, organic amendments
Procedia PDF Downloads 217854 Development and Characterisation of Nonwoven Fabrics for Apparel Applications
Authors: Muhammad Cheema, Tahir Shah, Subhash Anand
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The cost of making apparel fabrics for garment manufacturing is very high because of their conventional manufacturing processes and new methods/processes are being constantly developed for making fabrics by unconventional methods. With the advancements in technology and the availability of the innovative fibres, durable nonwoven fabrics by using the hydroentanglement process that can compete with the woven fabrics in terms of their aesthetic and tensile properties are being developed. In the work reported here, the hydroentangled nonwoven fabrics were developed through a hybrid nonwoven manufacturing processes by using fibrillated Tencel® and bi-component (sheath/core) polyethylene/polyester (PE/PET) fibres, in which the initial nonwoven fabrics were prepared by the needle-punching method followed by hydroentanglement process carried out at optimal pressures of 50 to 250bars. The prepared fabrics were characterized according to the British Standards (BS 3356:1990, BS 9237:1995, BS 13934-1:1999) and the attained results were compared with those for a standard plain-weave cotton, polyester woven fabric and commercially available nonwoven fabric (Evolon®). The developed hydroentangled fabrics showed better drape properties owing to their flexural rigidity of 252 mg.cm in the machine direction, while the corresponding commercial hydroentangled fabric displayed a value of 1340 mg.cm in the machine direction. The tensile strength of the developed hydroentangled fabrics showed an approximately 200% increase than the commercial hydroentangled fabrics. Similarly, the developed hydroentangled fabrics showed higher properties in term of air permeability, such as the developed hydroentangled fabric exhibited 448 mm/sec and Evolon fabric exhibited 69 mm/sec at 100 Pa pressure. Thus for apparel fabrics, the work combining the existing methods of nonwoven production, provides additional benefits in terms of cost, time and also helps in reducing the carbon footprint for the apparel fabric manufacture.Keywords: hydroentanglement, nonwoven apparel, durable nonwoven, wearable nonwoven
Procedia PDF Downloads 268853 Examining the Effect of Online English Lessons on Nursery School Children
Authors: Hidehiro Endo, Taizo Shigemichi
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Introduction & Objectives: In 2008, the revised course of study for elementary schools was published by MEXT, and from the beginning of the academic year of 2011-2012, foreign language activities (English lessons) became mandatory for 5th and 6th graders in Japanese elementary schools. Foreign language activities are currently offered once a week for approximately 50 minutes by elementary school teachers, assistant language teachers who are native speakers of English, volunteers, among others, with the purpose of helping children become accustomed to functional English. However, the new policy has disclosed a myriad of issues in conducting foreign language activities since the majority of the current elementary school teachers has neither English teaching experience nor English proficiency. Nevertheless, converting foreign language activities into English, as a subject in Japanese elementary schools (for 5th and 6th graders) from 2020 is what MEXT currently envisages with the purpose of reforming English education in Japan. According to their new proposal, foreign language activities will be mandatory for 3rd and 4th graders from 2020. Consequently, gaining better access to English learning opportunities becomes one of the primary concerns even in early childhood education. Thus, in this project, we aim to explore some nursery schools’ attempts at providing toddlers with online English lessons via Skype. The main purpose of this project is to look deeply into what roles online English lessons in the nursery schools play in guiding nursery school children to enjoy learning the English language as well as to acquire English communication skills. Research Methods: Setting; The main research site is a nursery school located in the northern part of Japan. The nursery school has been offering a 20-minute online English lesson via Skype twice a week to 7 toddlers since September 2015. The teacher of the online English lessons is a male person who lives in the Philippines. Fieldwork & Data; We have just begun collecting data by attending the Skype English lessons. Direct observations are the principal components of the fieldwork. By closely observing how the toddlers respond to what the teacher does via Skype, we examine what components stimulate the toddlers to pay attention to the English lessons. Preliminary Findings & Expected Outcomes: Although both data collection and analysis are ongoing, we found that the online English teacher remembers the first name of each toddler and calls them by their first name via Skype, a technique that is crucial in motivating the toddlers to actively participate in the lessons. In addition, when the teacher asks the toddlers the name of a plastic object such as grapes in English, the toddlers tend to respond to the teacher in Japanese. Accordingly, the effective use of Japanese in teaching English for nursery school children need to be further examined. The anticipated results of this project are an increased recognition of the significance of creating English language learning opportunities for nursery school children and a significant contribution to the field of early childhood education.Keywords: teaching children, English education, early childhood education, nursery school
Procedia PDF Downloads 329852 Production, Extraction and Purification of Fungal Chitosan and Its Modification for Medical Applications
Authors: Debajyoti Bose
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Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Chitosan is a positively charged natural biodegradable and biocompatible polymer. It is a linear polysaccharide consisting of β-1,4 linked monomers of glucosamine and N-acetylglucosamine. Chitosan can be mainly obtained from fungal sources during large fermentation process. In this study,three different fungal strains Aspergillus niger NCIM 1045, Aspergillus oryzae NCIM 645 and Mucor indicus MTCC 3318 were used for the production of chitosan. The growth mediums were optimized for maximum fungal production. The produced chitosan was characterized by determining degree of deacetylation. Chitosan possesses one reactive amino at the C-2 position of the glucosamine residue, and these amines confer important functional properties to chitosan which can be exploited for biofabrication to generate various chemically modified derivatives and explore their potential for pharmaceutical field. Chitosan nanoparticles were prepared by ionic cross-linking with tripolyphosphate (TPP). The major effect on encapsulation and release of protein (e.g. enzyme diastase) in chitosan-TPP nanoparticles was investigated in order to control the loading and release efficiency. It was noted that the chitosan loading and releasing efficiency as a nanocapsule, obtained from different fungal sources was almost near to initial enzyme activity(12026 U/ml) with a negligible loss. This signify, chitosan can be used as a polymeric drug as well as active component or protein carrier material in dosage by design due to its appealing properties such as biocompatibility, biodegradability, low toxicity and relatively low production cost from abundant natural sources. Based upon these initial experiments, studies were also carried out on modification of chitosan based nanocapsules incorporated with physiologically important enzymes and nutraceuticals for target delivery.Keywords: fungi, chitosan, enzyme, nanocapsule
Procedia PDF Downloads 502851 Association of Depression with Physical Inactivity and Time Watching Television: A Cross-Sectional Study with the Brazilian Population PNS, 2013
Authors: Margareth Guimaraes Lima, Marilisa Berti A. Barros, Deborah Carvalho Malta
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The relationship between physical activity (PA) and depression has been investigated, in both, observational and clinical studies: PA can integrate the treatments for depression; the physical inactivity (PI) may contribute to increase depression symptoms; and on the other hand, emotional problems can decrease PA. The main of this study was analyze the association among leisure and transportation PI and time watching television (TV) according to depression (minor and major), evaluated with the Patient Health Questionnaire (PHQ-9). The association was also analyzed by gender. This is a cross-sectional study. Data were obtained from the National Health Survey 2013 (PNS), performed with representative sample of the Brazilian adult population, in 2013. The PNS collected information from 60,202 individuals, aged 18 years or more. The independent variable were: leisure time physical inactivity (LTPI), considering inactive or insufficiently actives (categories were linked for analyzes), those who do not performed a minimum of 150 or 74 minutes of moderate or vigorous LTPA, respectively, by week; transportation physical inactivity (TPI), individuals who did not reached 150 minutes, by week, travelling by bicycle or on foot to work or other activities; daily time watching TV > 5 hours. The principal independent variable was depression, identified by PHQ-9. Individuals were classified with major depression, with > 5 symptoms, more than seven days, but one of the symptoms was “depressive mood” or “lack of interest or pleasure”. The others had minor depression. The variables used to adjustment were gender, age, schooling and chronic disease. The prevalence of LTPI, TPI and TV time were estimated according to depression, and differences were tested with Chi-Square test. Adjusted prevalence ratios were estimated using multiple Poisson regression models. The analyzes also had stratification by gender. Mean age of the studied population was 42.9 years old (CI95%:42.6-43.2) and 52.9% were women. 77.5% and 68.1% were inactive or insufficiently active in leisure and transportation, respectively and 13.3% spent time watching TV 5 > hours. 6% and 4.1% of the Brazilian population were diagnosed with minor or major depression. LTPI prevalence was 5% and 9% higher among individuals with minor and major depression, respectively, comparing with no depression. The prevalence of TPI was 7% higher in those with major depression. Considering larger time watching TV, the prevalence was 45% and 74% higher among those with minor and major depression, respectively. Analyzing by gender, the associations were greater in men than women and TPI was note be associated, in women. The study detected the higher prevalence of leisure time physical inactivity and, especially, time spent watching TV, among individuals with major and minor depression, after to adjust for a number of potential confounding factors. TPI was only associated with major disorders and among men. Considering the cross-sectional design of the research, these associations can point out the importance of the mental problems control of the population to increase PA and decrease the sedentary lifestyle; on the other hand, the study highlight the need of interventions by encouraging people with depression, to practice PA, even to transportation.Keywords: depression, physical activity, PHQ-9, sedentary lifestyle
Procedia PDF Downloads 156850 Characteristics of Meiofaunal Communities in Intertidal Habitats Along Albanian Adriatic Sea Coast
Authors: Fundime Miri, Emanuela Sulaj
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Benthic ecosystems constitute important ecological habitats, providing fundamental services for spawning, foraging, and sheltering aquatic organisms. Benthic faunal communities are characterized by a large biological diversity, supported by a great physical variety of benthic habitats. Until late, the study of meiobenthic communities in Albania has been neglectedthus excluding an important component of benthos. The present study aims to bring characteristics of distribution pattern of meiofaunal communities with further focus on nematode genus-based diversity from different intertidal habitats along Albanian Adriatic Sea Coast. The investigation area is extended from Shkodra to Vlora District, including six sandy sampling sites in beaches and areas near river estuaries. Sediment samples were collected manually in low intertidal zone by using a cylindrical corer, with an internal diameter of 5 cm. The richness onmeiofaunalmajor taxon level did not show any significant change between different sampling sites compare to significant changes in nematode diversity at genus level, with distinct nematode assemblages per sampling sites and presence of exclusive genera. All meiofaunal communities under study were dominated by nematodes. Further assessment of functional diversity on nematode assemblages exhibited changes as well on trophic groups and life strategies due to diverse feeding behaviors and c-p values of nematode genera. This study emphasize the need for lower level taxonomic identification of meiofaunal organisms and extending of ecological assessments on trophic diversity and life strategies to understanding functional consequences.Keywords: benthos, meiofauna, nematode genus-based diversity, functional diversity, intertidal, albanian adriatic coast
Procedia PDF Downloads 149849 Land Use Change Detection Using Satellite Images for Najran City, Kingdom of Saudi Arabia (KSA)
Authors: Ismail Elkhrachy
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Determination of land use changing is an important component of regional planning for applications ranging from urban fringe change detection to monitoring change detection of land use. This data are very useful for natural resources management.On the other hand, the technologies and methods of change detection also have evolved dramatically during past 20 years. So it has been well recognized that the change detection had become the best methods for researching dynamic change of land use by multi-temporal remotely-sensed data. The objective of this paper is to assess, evaluate and monitor land use change surrounding the area of Najran city, Kingdom of Saudi Arabia (KSA) using Landsat images (June 23, 2009) and ETM+ image(June. 21, 2014). The post-classification change detection technique was applied. At last,two-time subset images of Najran city are compared on a pixel-by-pixel basis using the post-classification comparison method and the from-to change matrix is produced, the land use change information obtained.Three classes were obtained, urban, bare land and agricultural land from unsupervised classification method by using Erdas Imagine and ArcGIS software. Accuracy assessment of classification has been performed before calculating change detection for study area. The obtained accuracy is between 61% to 87% percent for all the classes. Change detection analysis shows that rapid growth in urban area has been increased by 73.2%, the agricultural area has been decreased by 10.5 % and barren area reduced by 7% between 2009 and 2014. The quantitative study indicated that the area of urban class has unchanged by 58.2 km〗^2, gained 70.3 〖km〗^2 and lost 16 〖km〗^2. For bare land class 586.4〖km〗^2 has unchanged, 53.2〖km〗^2 has gained and 101.5〖km〗^2 has lost. While agriculture area class, 20.2〖km〗^2 has unchanged, 31.2〖km〗^2 has gained and 37.2〖km〗^2 has lost.Keywords: land use, remote sensing, change detection, satellite images, image classification
Procedia PDF Downloads 524848 Climate Change and Landslide Risk Assessment in Thailand
Authors: Shotiros Protong
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The incidents of sudden landslides in Thailand during the past decade have occurred frequently and more severely. It is necessary to focus on the principal parameters used for analysis such as land cover land use, rainfall values, characteristic of soil and digital elevation model (DEM). The combination of intense rainfall and severe monsoons is increasing due to global climate change. Landslide occurrences rapidly increase during intense rainfall especially in the rainy season in Thailand which usually starts around mid-May and ends in the middle of October. The rain-triggered landslide hazard analysis is the focus of this research. The combination of geotechnical and hydrological data are used to determine permeability, conductivity, bedding orientation, overburden and presence of loose blocks. The regional landslide hazard mapping is developed using the Slope Stability Index SINMAP model supported on Arc GIS software version 10.1. Geological and land use data are used to define the probability of landslide occurrences in terms of geotechnical data. The geological data can indicate the shear strength and the angle of friction values for soils above given rock types, which leads to the general applicability of the approach for landslide hazard analysis. To address the research objectives, the methods are described in this study: setup and calibration of the SINMAP model, sensitivity of the SINMAP model, geotechnical laboratory, landslide assessment at present calibration and landslide assessment under future climate simulation scenario A2 and B2. In terms of hydrological data, the millimetres/twenty-four hours of average rainfall data are used to assess the rain triggered landslide hazard analysis in slope stability mapping. During 1954-2012 period, is used for the baseline of rainfall data at the present calibration. The climate change in Thailand, the future of climate scenarios are simulated by spatial and temporal scales. The precipitation impact is need to predict for the climate future, Statistical Downscaling Model (SDSM) version 4.2, is used to assess the simulation scenario of future change between latitude 16o 26’ and 18o 37’ north and between longitude 98o 52’ and 103o 05’ east by SDSM software. The research allows the mapping of risk parameters for landslide dynamics, and indicates the spatial and time trends of landslide occurrences. Thus, regional landslide hazard mapping under present-day climatic conditions from 1954 to 2012 and simulations of climate change based on GCM scenarios A2 and B2 from 2013 to 2099 related to the threshold rainfall values for the selected the study area in Uttaradit province in the northern part of Thailand. Finally, the landslide hazard mapping will be compared and shown by areas (km2 ) in both the present and the future under climate simulation scenarios A2 and B2 in Uttaradit province.Keywords: landslide hazard, GIS, slope stability index (SINMAP), landslides, Thailand
Procedia PDF Downloads 564847 Direct Approach in Modeling Particle Breakage Using Discrete Element Method
Authors: Ebrahim Ghasemi Ardi, Ai Bing Yu, Run Yu Yang
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Current study is aimed to develop an available in-house discrete element method (DEM) code and link it with direct breakage event. So, it became possible to determine the particle breakage and then its fragments size distribution, simultaneous with DEM simulation. It directly applies the particle breakage inside the DEM computation algorithm and if any breakage happens the original particle is replaced with daughters. In this way, the calculation will be followed based on a new updated particles list which is very similar to the real grinding environment. To validate developed model, a grinding ball impacting an unconfined particle bed was simulated. Since considering an entire ball mill would be too computationally demanding, this method provided a simplified environment to test the model. Accordingly, a representative volume of the ball mill was simulated inside a box, which could emulate media (ball)–powder bed impacts in a ball mill and during particle bed impact tests. Mono, binary and ternary particle beds were simulated to determine the effects of granular composition on breakage kinetics. The results obtained from the DEM simulations showed a reduction in the specific breakage rate for coarse particles in binary mixtures. The origin of this phenomenon, commonly known as cushioning or decelerated breakage in dry milling processes, was explained by the DEM simulations. Fine particles in a particle bed increase mechanical energy loss, and reduce and distribute interparticle forces thereby inhibiting the breakage of the coarse component. On the other hand, the specific breakage rate of fine particles increased due to contacts associated with coarse particles. Such phenomenon, known as acceleration, was shown to be less significant, but should be considered in future attempts to accurately quantify non-linear breakage kinetics in the modeling of dry milling processes.Keywords: particle bed, breakage models, breakage kinetic, discrete element method
Procedia PDF Downloads 199846 The Role of the STAT3 Signaling for Melatonergic Synthetic Pathway in the Rat Pineal Gland
Authors: Simona Moravcova, Jiri Novotny, Zdenka Bendova
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The pineal gland of the vertebrate brain is a circumventricular organ which serves as a major neuroendocrine gland with the primary function of rhythmic secretion of neurohormone melatonin under the control of the hypothalamic suprachiasmatic nucleus (SCN). Soon after the onset of the darkness, the activity of the key rate-limiting enzyme for melatonin synthesis, arylalkylamine N-acetyltransferase (AANAT), raises due to the increased release of norepinephrine from sympathetic neurons terminating on the parenchymal cells where it binds to β-adrenergic receptors. Melatonin codes the length of the night, and it is well recognized for its anti-inflammatory effects. However, to our knowledge, less is known about the effect of the immune system on the melatonin biosynthesis and the precise role of the STAT3 in the signaling pathway leading to the expression of AANAT. Lipopolysaccharide (LPS) is the essential component in the outer surface membrane of gram-negative bacteria and acts as a strong stimulator of natural and innate immunity. STAT3 acts as an important factor in immune response. Here we investigated the effect of LPS on the components of the melatonergic synthetic pathway in the pineal gland. The experiments were performed both in vivo and in vitro. The changes in AANAT activity were determined by radioenzymatic assay. PCR analyses were carried out to detect aa-nat, icer, spi-3 and stat3 gene expression. From our results, it is apparent that the high basal level of phosphorylated forms of STAT3 can be elevated after systemic as well as in vitro administration of LPS. Our experiments have shown that LPS reduces melatonin synthesis, nevertheless, the activity of AANAT was increased. Moreover, the basal level of phosphorylated STAT3 counteracts β-adrenergic receptor-mediated aa-nat gene expression and sustains its own and spi-3 gene expression. In conclusion, LPS can affect immunomodulators such as melatonin in the pineal gland.Keywords: AANAT, lipopolysaccharide, pineal gland, rat, STAT3
Procedia PDF Downloads 169845 The Effect of Principled Human Resource Management and Training Based on Existing Standards in Order to Improve the Quality of Construction Projects
Authors: Arsalan Salahi
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Today, the number of changes in the construction industry and urban mass house building is increasing, which makes you need to pay more attention to targeted planning for human resource management and training. The human resources working in the construction industry have various problems and deficiencies, and in order to solve these problems, there is a need for basic management and training of these people in order to lower the construction costs and increase the quality of the projects, especially in mass house building projects. The success of any project in reaching short and long-term professional goals depends on the efficient combination of work tools, financial resources, raw materials, and most importantly, human resources. Today, due to the complexity and diversity of each project, specialized management fields have emerged to maximize the potential benefits of each component of that project. Human power is known as the most important resource in construction projects for its successful implementation, but unfortunately, due to the low cost of human power compared to other resources, such as materials and machinery, little attention is paid to it. With the correct management and training of human resources, which depends on its correct planning and development, it is possible to improve the performance of construction projects. In this article, the training and motivation of construction industry workers and their effects on the effectiveness of projects in this industry have been researched. In this regard, some barriers to the training and motivation of construction workers and personnel have been identified and solutions have been provided for construction companies. Also, the impact of workers and unskilled people on the efficiency of construction projects is investigated. The results of the above research show that by increasing the use of correct and basic training for human resources, we will see positive results and effects on the performance of construction projects.Keywords: human resources, construction industry, principled training, skilled and unskilled workers
Procedia PDF Downloads 96844 Transit-Oriented Development as a Tool for Building Social Capital
Authors: Suneet Jagdev
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Rapid urbanization has resulted in informal settlements on the periphery of nearly all big cities in the developing world due to lack of affordable housing options in the city. Residents of these communities have to travel long distances to get to work or search for jobs in these cities, and women, children and elderly people are excluded from urban opportunities. Affordable and safe public transport facilities can help them expand their possibilities. The aim of this research is to identify social capital as another important element of livable cities that can be protected and nurtured through transit-oriented development, as a tool to provide real resources that can help these transit-oriented communities become self-sustainable. Social capital has been referred to the collective value of all social networks and the inclinations that arise from these networks to do things for each other. It is one of the key component responsible to build and maintain democracy. Public spaces, pedestrian amenities and social equity are the other essential part of Transit Oriented Development models that will be analyzed in this research. The data has been collected through the analysis of several case studies, the urban design strategies implemented and their impact on the perception and on the community´s experience, and, finally, how these focused on the social capital. Case studies have been evaluated on several metrics, namely ecological, financial, energy consumption, etc. A questionnaire and other tools were designed to collect data to analyze the research objective and reflect the dimension of social capital. The results of the questionnaire indicated that almost all the participants have a positive attitude towards this dimensions of building a social capital with the aid of transit-oriented development. Statistical data of the identified key motivators against against demographic characteristics have been generated based on the case studies used for the paper. The findings suggested that there is a direct relation between urbanization, transit-oriented developments, and social capital.Keywords: better opportunities, low-income settlements, social capital, social inclusion, transit oriented development
Procedia PDF Downloads 331843 Process Development for the Conversion of Organic Waste into Valuable Products
Authors: Ife O. Bolaji
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Environmental concerns arising from the use of fossil fuels has increased the interest in the development of renewable and sustainable sources of energy. This would minimize the dependence on fossil fuels and serve as future alternatives. Organic wastes contain carbohydrates, proteins and lipids, which can be utilised as carbon sources for the production of bio-based products. Cellulose is the most abundant natural biopolymer, being the main structural component of lignocellulosic materials. The aim of this project is to develop a biological process for the hydrolysis and fermentation of organic wastes into ethanol and organic acids. The hydrolysis and fermentation processes are integrated in a single vessel using undefined mixed culture microorganisms. The anaerobic fermentation of microcrystalline cellulose was investigated in continuous and batch reactors at 25°C with an appropriate growth medium for cellulase formation, hydrolysis, and fermentation. The reactors were inoculated with soil (B1, C1, C3) or sludge from an anaerobic digester (B2, C2) and the breakdown of cellulose was monitored by measuring the production of ethanol, organic acids and the residual cellulose. The batch reactors B1 and B2 showed negligible microbial activity due to inhibition while the continuous reactors, C1, C2 and C3, exhibited little cellulose hydrolysis which was concealed by the cellulose accumulation in the reactor. At the end of the continuous operation, the reactors C1, C2 and C3 were operated under batch conditions. 48%, 34% and 42% cellulose had been fermented by day 88, 55 and 55 respectively of the batch fermentation. Acetic acid, ethanol, propionic acid and butyric acids were the main fermentation products in the reactors. A stable concentration of 0.6 g/l ethanol and 5 g/L acetic acid was maintained in C3 for several weeks due to reduced activity of methanogens caused by the decrease in pH. Thus far, the results have demonstrated that mixed microbial culture is capable of hydrolysing and fermenting cellulose under lenient conditions. The fermentation of cellulose has been found effective in a combination of continuous and batch processes.Keywords: cellulose, hydrolysis, mixed culture, organic waste
Procedia PDF Downloads 367842 Curcumin Derivatives as Potent Inhibitors of Inducible Nitric Oxide Synthase in Osteoarthritis: A Molecular Docking Study
Authors: F. Ambreen, A.Naheed
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Osteoarthritis (OA) is a degenerative disorder affecting millions of people worldwide. Nitric oxide (NO) was found to play a catabolic role in the development of osteoarthritis. It is a toxic free radical gas generated during the metabolism of L-arginine by the enzyme Nitric oxide synthase (NOS). Inducible Nitric Oxide Synthase (iNOS) is one of the isoform of NOS, and its overexpression leads to the excessive formation of NO that results in pathophysiological joint conditions. Several synthetic anti-inflammatory drugs and inhibitors are present to date, but all showed side effects and complications. Therefore, the pursuit of natural disease-modifying drugs remains a top priority. Curcumin is an active component of turmeric, and the past few decades have witnessed intense research devoted to the antioxidant and anti-inflammatory properties of curcumin. The present study focused on curcumin and its derivatives in the search for new iNOS inhibitors for the treatment of osteoarthritis. We conducted a molecular docking study on curcumin and its four derivatives; cyclocurcumin, tetrahydrocurcumin, demethoxycurcumin and curcumin monoglucoside with iNOS using CLC Drug discovery work bench 3.02. We selected two co-crystallized ligands for this study; tetrahydrobiopterin and N-omega-propyl-L-arginine present in complex with the enzyme iNOS. Results showed the best binding affinity of N-omega-propyl-L-arginine with cyclocurcumin and curcumin monoglucoside that exhibit binding energies of -65.2 kcal/mol and -68 kcal/mol respectively. Whereas with tetrahydrobiopterin, best binding scores of -64.7 kcal/mol and -62.2 kcal/mol were found with tetrahydrocurcumin and demethoxycurcumin respectively. This information could open doors of research for the designing of novel drugs using herbs such as curcumin for the treatment of inflammatory joint diseases.Keywords: curcumin, iNOS, molecular docking, osteoarthritis
Procedia PDF Downloads 129841 Localized Detection of ᴅ-Serine by Using an Enzymatic Amperometric Biosensor and Scanning Electrochemical Microscopy
Authors: David Polcari, Samuel C. Perry, Loredano Pollegioni, Matthias Geissler, Janine Mauzeroll
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ᴅ-serine acts as an endogenous co-agonist for N-methyl-ᴅ-aspartate receptors in neuronal synapses. This makes it a key component in the development and function of a healthy brain, especially given its role in several neurodegenerative diseases such as Alzheimer’s disease and dementia. Despite such clear research motivations, the primary site and mechanism of ᴅ-serine release is still currently unclear. For this reason, we are developing a biosensor for the detection of ᴅ-serine utilizing a microelectrode in combination with a ᴅ-amino acid oxidase enzyme, which produces stoichiometric quantities of hydrogen peroxide in response to ᴅ-serine. For the fabrication of a biosensor with good selectivity, we use a permselective poly(meta-phenylenediamine) film to ensure only the target molecule is reacted, according to the size exclusion principle. In this work, we investigated the effect of the electrodeposition conditions used on the biosensor’s response time and selectivity. Careful optimization of the fabrication process allowed for enhanced biosensor response time. This allowed for the real time sensing of ᴅ-serine in a bulk solution, and also provided in means to map the efflux of ᴅ-serine in real time. This was done using scanning electrochemical microscopy (SECM) with the optimized biosensor to measure localized release of ᴅ-serine from an agar filled glass capillary sealed in an epoxy puck, which acted as a model system. The SECM area scan simultaneously provided information regarding the rate of ᴅ-serine flux from the model substrate, as well as the size of the substrate itself. This SECM methodology, which provides high spatial and temporal resolution, could be useful to investigate the primary site and mechanism of ᴅ-serine release in other biological samples.Keywords: ᴅ-serine, enzymatic biosensor, microelectrode, scanning electrochemical microscopy
Procedia PDF Downloads 228840 J-Integral Method for Assessment of Structural Integrity of a Pressure Vessel
Authors: Karthik K. R, Viswanath V, Asraff A. K
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The first stage of a new-generation launch vehicle of ISRO makes use of large pressure vessels made of Aluminium alloy AA2219 to store fuel and oxidizer. These vessels have many weld joints that may contain cracks or crack-like defects during their fabrication. These defects may propagate across the vessel during pressure testing or while in service under the influence of tensile stresses leading to catastrophe. Though ductile materials exhibit significant stable crack growth prior to failure, it is not generally acceptable for an aerospace component. There is a need to predict the initiation of stable crack growth. The structural integrity of the vessel from fracture considerations can be studied by constructing the Failure Assessment Diagram (FAD) that accounts for both brittle fracture and plastic collapse. Critical crack sizes of the pressure vessel may be highly conservative if it is predicted from FAD alone. If the J-R curve for material under consideration is available apriori, the critical crack sizes can be predicted to a certain degree of accuracy. In this paper, a novel approach is proposed to predict the integrity of a weld in a pressure vessel made of AA2219 material. Fracture parameter ‘J-integral’ at the crack front, evaluated through finite element analyses, is used in the new procedure. Based on the simulation of tension tests carried out on SCT specimens by NASA, a cut-off value of J-integral value (J?ᵤₜ_ₒ??) is finalised. For the pressure vessel, J-integral at the crack front is evaluated through FE simulations incorporating different surface cracks at long seam weld in a cylinder and in dome petal welds. The obtained J-integral, at vessel level, is compared with a value of J?ᵤₜ_ₒ??, and the integrity of vessel weld in the presence of the surface crack is firmed up. The advantage of this methodology is that if SCT test data of any metal is available, the critical crack size in hardware fabricated using that material can be predicted to a better level of accuracy.Keywords: FAD, j-integral, fracture, surface crack
Procedia PDF Downloads 187839 Studies on the Characterization and Machinability of Duplex Stainless Steel 2205 during Dry Turning
Authors: Gaurav D. Sonawane, Vikas G. Sargade
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The present investigation is a study of the effect of advanced Physical Vapor Deposition (PVD) coatings on cutting temperature residual stresses and surface roughness during Duplex Stainless Steel (DSS) 2205 turning. Austenite stabilizers like nickel, manganese, and molybdenum reduced the cost of DSS. Surface Integrity (SI) plays an important role in determining corrosion resistance and fatigue life. Resistance to various types of corrosion makes DSS suitable for applications with critical environments like Heat exchangers, Desalination plants, Seawater pipes and Marine components. However, lower thermal conductivity, poor chip control and non-uniform tool wear make DSS very difficult to machine. Cemented carbide tools (M grade) were used to turn DSS in a dry environment. AlTiN and AlTiCrN coatings were deposited using advanced PVD High Pulse Impulse Magnetron Sputtering (HiPIMS) technique. Experiments were conducted with cutting speed of 100 m/min, 140 m/min and 180 m/min. A constant feed and depth of cut of 0.18 mm/rev and 0.8 mm were used, respectively. AlTiCrN coated tools followed by AlTiN coated tools outperformed uncoated tools due to properties like lower thermal conductivity, higher adhesion strength and hardness. Residual stresses were found to be compressive for all the tools used for dry turning, increasing the fatigue life of the machined component. Higher cutting temperatures were observed for coated tools due to its lower thermal conductivity, which results in very less tool wear than uncoated tools. Surface roughness with uncoated tools was found to be three times higher than coated tools due to lower coefficient of friction of coating used.Keywords: cutting temperature, DSS2205, dry turning, HiPIMS, surface integrity
Procedia PDF Downloads 134838 Implementation of Research Papers and Industry Related Experiments by Undergraduate Students in the Field of Automation
Authors: Veena N. Hegde, S. R. Desai
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Motivating a heterogeneous group of students towards engagement in research related activities is a challenging task in engineering education. An effort is being made at the Department of Electronics and Instrumentation Engineering, where two courses are taken up on a pilot basis to kindle research interests in students at the undergraduate level. The courses, namely algorithm and system design (ASD) and automation in process control (APC), are selected for experimentation purposes. The task is being accomplished by providing scope for implementation of research papers and proposing solutions for the current industrial problems by the student teams. The course instructors have proposed an alternative assessment tool to evaluate the undergraduate students that involve activities beyond the curriculum. The method was tested for the aforementioned two courses in a particular academic year, and as per the observations, there is a considerable improvement in the number of student engagement towards research in the subsequent years of their undergraduate course. The student groups from the third-year engineering were made to read, implement the research papers, and they were also instructed to develop simulation modules for certain processes aiming towards automation. The target audience being students, were common for both the courses and the students' strength was 30. Around 50% of successful students were given the continued tasks in the subsequent two semesters, and out of 15 students who continued from sixth semesters were able to follow the research methodology well in the seventh and eighth semesters. Further, around 30% of the students out of 15 ended up carrying out project work with a research component involved and were successful in producing four conference papers. The methodology adopted is justified using a sample data set, and the outcomes are highlighted. The quantitative and qualitative results obtained through this study prove that such practices will enhance learning experiences substantially at the undergraduate level.Keywords: industrial problems, learning experiences, research related activities, student engagement
Procedia PDF Downloads 165837 Adsorption Behavior and Mechanism of Illite Surface under the Action of Different Surfactants
Authors: Xiuxia Sun, Yan Jin, Zilong Liu, Shiming Wei
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As a critical mineral component of shale, illite is essential in oil exploration and development due to its surface hydration characteristics and action mechanism. This paper, starting from the perspective of the molecular structure of organic matter, uses molecular dynamics simulation technology to deeply explore the interaction mechanism between organic molecules and the illite surface. In the study, we thoroughly considered the forces such as van der Waals force, electrostatic force, and steric hindrance and constructed an illite crystal model covering C8-C18 modifiers. Subsequently, we systematically analyzed surfactants' adsorption behavior and hydration characteristics with different alkyl chain numbers, lengths, and concentrations on the illite surface. The simulation results show that surfactant molecules with shorter alkyl chains present a lateral monolayer or inclined double-layer arrangement on the illite surface, and these two arrangements may coexist under different concentration conditions. In addition, with the increase in the number of alkyl chains, the interlayer spacing of illite increases significantly. In contrast, the change in alkyl chain length has a limited effect on surface properties. It is worth noting that the change in functional group structure has a particularly significant effect on the wettability of the illite surface, and its influence even exceeds the change in the alkyl chain structure. This discovery gives us a new perspective on understanding and regulating the wetting properties. The results obtained are consistent with the XRD analysis and wettability experimental data in this paper, further confirming the reliability of the research conclusions. This study deepened our understanding of illite's hydration characteristics and mechanism. We provided new ideas and directions for the molecular design and application development of oilfield chemicals.Keywords: illite, surfactant, hydration, wettability, adsorption
Procedia PDF Downloads 42836 Teaching Foreign Languages Across the Curriculum (FLAC): Hybrid French/English Courses and their Dual Impact on Interdisciplinarity and L2 Competency
Authors: M. Caporale
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French Curricula across the US have recently suffered low enrollment and have experienced difficulties with retention, thus resulting in fewer students minoring and majoring in French and enrolling in upper-level classes. Successful undergraduate programs offer French courses with a strong cultural and interdisciplinary or multidisciplinary component. The World Language Curriculum in liberal arts colleges in America needs to take into account the cultural aspects of the language and encourage students to think critically about the country or countries they are studying. Limiting the critical inquiry to language or literature narrowly defined provides and incomplete and stagnant picture of France and the Francophone world in today's global community. This essay discusses the creation and implementation of a hybrid interdisciplinary L1/L2 course titled "Topics in Francophone Cinema" (subtitle "Francophone Women on Screen and Behind the Camera"). Content-based interdisciplinary courses undoubtedly increase the profile of French and Francophone cultural Studies by introducing students of other disciplines to fundamental questions relating to the French and Francophone cultures (in this case, women's rights in the Francophone world). At the same time, this study determines that through targeted reading and writing assignments, sustained aural exposure to L2 through film,and student participation in a one-credit supplementary weekly practicum (creative film writing workshop), significant advances in L2 competence are achieved with students' oral and written production levels evolving from Advanced Low to Advanced-mid, as defined by the ACFL guidelines. Use of differentiated assessment methods for L1/L2 and student learning outcomes for both groups will also be addressed.Keywords: interdisciplinary, Francophone cultural studies, language competency, content-based
Procedia PDF Downloads 500