Search results for: power conservation
643 Modification of Carbon-Based Gas Sensors for Boosting Selectivity
Authors: D. Zhao, Y. Wang, G. Chen
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Gas sensors that utilize carbonaceous materials as sensing media offer numerous advantages, making them the preferred choice for constructing chemical sensors over those using other sensing materials. Carbonaceous materials, particularly nano-sized ones like carbon nanotubes (CNTs), provide these sensors with high sensitivity. Additionally, carbon-based sensors possess other advantageous properties that enhance their performance, including high stability, low power consumption for operation, and cost-effectiveness in their construction. These properties make carbon-based sensors ideal for a wide range of applications, especially in miniaturized devices created through MEMS or NEMS technologies. To capitalize on these properties, a group of chemoresistance-type carbon-based gas sensors was developed and tested against various volatile organic compounds (VOCs) and volatile inorganic compounds (VICs). The results demonstrated exceptional sensitivity to both VOCs and VICs, along with the sensor’s long-term stability. However, this broad sensitivity also led to poor selectivity towards specific gases. This project aims at addressing the selectivity issue by modifying the carbon-based sensing materials and enhancing the sensor's specificity to individual gas. Multiple groups of sensors were manufactured and modified using proprietary techniques. To assess their performance, we conducted experiments on representative sensors from each group to detect a range of VOCs and VICs. The VOCs tested included acetone, dimethyl ether, ethanol, formaldehyde, methane, and propane. The VICs comprised carbon monoxide (CO), carbon dioxide (CO2), hydrogen (H2), nitric oxide (NO), and nitrogen dioxide (NO2). The concentrations of the sample gases were all set at 50 parts per million (ppm). Nitrogen (N2) was used as the carrier gas throughout the experiments. The results of the gas sensing experiments are as follows. In Group 1, the sensors exhibited selectivity toward CO2, acetone, NO, and NO2, with NO2 showing the highest response. Group 2 primarily responded to NO2. Group 3 displayed responses to nitrogen oxides, i.e., both NO and NO2, with NO2 slightly surpassing NO in sensitivity. Group 4 demonstrated the highest sensitivity among all the groups toward NO and NO2, with NO2 being more sensitive than NO. In conclusion, by incorporating several modifications using carbon nanotubes (CNTs), sensors can be designed to respond well to NOx gases with great selectivity and without interference from other gases. Because the response levels to NO and NO2 from each group are different, the individual concentration of NO and NO2 can be deduced.Keywords: gas sensors, carbon, CNT, MEMS/NEMS, VOC, VIC, high selectivity, modification of sensing materials
Procedia PDF Downloads 116642 Individual Cylinder Ignition Advance Control Algorithms of the Aircraft Piston Engine
Authors: G. Barański, P. Kacejko, M. Wendeker
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The impact of the ignition advance control algorithms of the ASz-62IR-16X aircraft piston engine on a combustion process has been presented in this paper. This aircraft engine is a nine-cylinder 1000 hp engine with a special electronic control ignition system. This engine has two spark plugs per cylinder with an ignition advance angle dependent on load and the rotational speed of the crankshaft. Accordingly, in most cases, these angles are not optimal for power generated. The scope of this paper is focused on developing algorithms to control the ignition advance angle in an electronic ignition control system of an engine. For this type of engine, i.e. radial engine, an ignition advance angle should be controlled independently for each cylinder because of the design of such an engine and its crankshaft system. The ignition advance angle is controlled in an open-loop way, which means that the control signal (i.e. ignition advance angle) is determined according to the previously developed maps, i.e. recorded tables of the correlation between the ignition advance angle and engine speed and load. Load can be measured by engine crankshaft speed or intake manifold pressure. Due to a limited memory of a controller, the impact of other independent variables (such as cylinder head temperature or knock) on the ignition advance angle is given as a series of one-dimensional arrays known as corrective characteristics. The value of the ignition advance angle specified combines the value calculated from the primary characteristics and several correction factors calculated from correction characteristics. Individual cylinder control can proceed in line with certain indicators determined from pressure registered in a combustion chamber. Control is assumed to be based on the following indicators: maximum pressure, maximum pressure angle, indicated mean effective pressure. Additionally, a knocking combustion indicator was defined. Individual control can be applied to a single set of spark plugs only, which results from two fundamental ideas behind designing a control system. Independent operation of two ignition control systems – if two control systems operate simultaneously. It is assumed that the entire individual control should be performed for a front spark plug only and a rear spark plug shall be controlled with a fixed (or specific) offset relative to the front one or from a reference map. The developed algorithms will be verified by simulation and engine test sand experiments. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.Keywords: algorithm, combustion process, radial engine, spark plug
Procedia PDF Downloads 286641 Engaging Medical Students in Research through Student Research Mentorship Programme
Authors: Qi En Han, Si En Wai, Eugene Quek
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As one of the two Academic Medical Centres (AMCs) in Singapore, SingHealth Duke-NUS AMC strives to improve patients’ lives through excellent clinical care, research and education. These efforts are enhanced with the establishment of Academic Clinical Programmes (ACPs). Each ACP brings together specialists in a particular discipline from different institutions to maximize the power of shared knowledge and resources. Initiated by Surgery ACP, the student research mentorship programme is a programme designed to facilitate engagement between medical students and the surgical faculty. The programme offers mentors not only the opportunity to supervise research but also to nurture future clinician scientists. In turn, medical students acquire valuable research experience which may be useful in their future careers. The programme typically lasts one year, depending on the students’ commitment. Surgery ACP matches students’ research interests with the mentor's area of expertise whenever possible. Surgery ACP organizes informal tea sessions to bring students and prospective mentors together. Once a match is made, the pair is required to submit a project proposal which includes the title, proposed start and end dates, ethical and biosafety considerations and project details. The mentees either think of their own research question with guidance from the mentors or join an existing project. The mentees may participate in data collection, data analysis, manuscript writing and conference presentation. The progress of each research project is monitored through half-yearly progress report. The mentees report problems encountered or changes made to existing proposal on top of the progress made. A total of 18 mentors were successfully paired with 36 mentees since 2013. Currently, there are 23 on-going and 13 completed projects. The mentees are encouraged to present their projects at conferences and to publish in peer-reviewed journals. Six mentees have presented their completed projects at local or international conferences and one mentee has her work published. To further support student research, Surgery ACP organized a Research Day in 2015 to recognize their research efforts and to showcase their wide-range of research. Surgery ACP recognizes that early exposure of medical students to research is important in developing them into clinician scientists. As interest in research take time to develop and are usually realized during various research attachments, it is crucial that programmes such as the student research mentorship programme exist. Surgery ACP will continue to build on this programme.Keywords: academic clinical programme, clinician scientist, medical student, mentoring
Procedia PDF Downloads 210640 From Stalemate to Progress: Navigating the Restitution Maze in Belgium and DRCongo
Authors: Gracia Lwanzo Kasongo
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In the realm of cultural heritage, few issues loom larger than the ongoing battle for restitution faced by European and African museums. In Belgium, this contentious process was set in motion by two pivotal events. Firstly, the resounding revelations of the French report on restitution, which boldly declared that 'over 90% of African cultural heritage resides outside of Africa Secondly, the seismic impact of the Black Lives Matter movement following the tragic death of George Floyd. These two events unleashed a wave of outrage among Afro-descendants, who viewed the possession of colonial collections as an enduring symbol of colonial dominance and a stark validation of the systemic racism deeply ingrained within Belgian society. The instrumentalization of cultural property as a means of wielding political power is by no means a novel concept. Its roots can be traced back to the constructed justifications that emerged in the 1950s, during which the Royal Museum for Central Africa in Tervuren played a pivotal role as the self-proclaimed 'guardian of Congolese cultural heritage'. This legacy of legitimizing colonial presence permeates the fabric of Belgium's museum reform policies and the structural management of museums in the Democratic Republic of Congo (DRC). Employing a dialectical approach, I embark on an exploration of the intricate historical interplay between the Royal Museum for Central Africa and the Institute of National Museums of Congo. From this vantage point, I delve into the arduous struggles faced by museums in both the DRC and Belgium as they grapple with the complex and contentious issue of cultural heritage restitution. Central to these struggles is the profound quest for meaning and (re)definition of museums, particularly for Congolese and Afro-descendant communities whose identities and narratives have long been marginalized and suppressed. As the narrative unfolds, I shed light on the prospects for cooperation that have emerged from my extensive fieldwork. Within the interplay of historical entanglements, struggles for restitution, and the search for a more inclusive and equitable museum landscape, glimmers of hope emerge. Collaborative efforts and potential avenues for mutual understanding between Belgium and the DRC begin to take shape, offering a beacon of possibility amidst the often tumultuous discourse surrounding cultural heritage.Keywords: restitution, museum stuggles, belgium, DRCongo
Procedia PDF Downloads 68639 Evaluation of Health Services after Emergency Decrees in Turkey
Authors: Sengul Celik, Alper Ketenci
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In Turkish Constitution about health care in Article 56, it is said that: everyone has the right to live in a healthy and balanced environment. It is the duty of the state and citizens to improve the environment, protect environmental health, and prevent environmental pollution. The state ensures that everyone lives their lives in physical and mental health; it organizes the planning and service of health institutions from a single source in order to realize cooperation by increasing savings and efficiency in human and substance power. The state fulfills this task by utilizing and supervising health and social institutions in the public and private sectors. General health insurance can be established by law for the widespread delivery of health services. To have health care is one of the basic rights of patients. After the coupe attempt in July 2016, the Government of Turkey has announced a state of emergency and issued lots of emergency decrees. By these emergency decrees, lots of people were dismissed from their jobs and lost their some basic social rights. The violations occur in social life. One of the most common observations is the discrimination by government in health care system. This study aims to put forward the violation of human rights in health care system in Turkey due to their discriminated position by an emergency decree. The study is a case study that is based on nine interviews with the people or relatives of people who lost their jobs by an emergency decree in Turkey. In this study, no personally identifiable information was obtained for the safety of individuals. Also no distinctive questions regarding the identity of individuals were asked. The interviews are obtained through internet call applications. The data were analyzed through the requirements of regular health care system in Turkey. The interviews expose that the people or the relatives of people lost their right to have regular health care. They have to pay extra amount both in clinical services and in medication treatment. The patient right to quality medical care without prejudice is violated. It was assessed that the people who are involved in emergency decree and their relatives are discriminated by government and deprived of regular medical care and supervision. Although international legal arrangements and legal responsibilities of the state have been put forward by Article 56, they are violated in practice. To prevent these kinds of violations, some measures should be taken against the deprivation in health care system especially towards the discriminated people by an emergency decree.Keywords: emergency decree in Turkey, health care, discriminated people, patients rights
Procedia PDF Downloads 102638 Administrative Supervision of Local Authorities’ Activities in Selected European Countries
Authors: Alina Murtishcheva
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The development of an effective system of administrative supervision is a prerequisite for the functioning of local self-government on the basis of the rule of law. Administrative supervision of local self-government is of particular importance in the EU countries due to the influence of integration processes. The central authorities act on the international level; however, subnational authorities also have to implement European legislation in order to strengthen integration. Therefore, the central authority, being the connecting link between supranational and subnational authorities, should bear responsibility, including financial responsibility, for possible mistakes of subnational authorities. Consequently, the state should have sufficient mechanisms of control over local and regional authorities in order to correct their mistakes. At the same time, the control mechanisms do not deny the autonomy of local self-government. The paper analyses models of administrative supervision of local self-government in Ukraine, Poland, Lithuania, Belgium, Great Britain, Italy, and France. The research methods used in this paper are theoretical methods of analysis of scientific literature, constitutions, legal acts, Congress of Local and Regional Authorities of the Council of Europe reports, and constitutional court decisions, as well as comparative and logical analysis. The legislative basis of administrative supervision was scrutinized, and the models of administrative supervision were classified, including a priori control and ex-post control or their combination. The advantages and disadvantages of these models of administrative supervision are analysed. Compliance with Article 8 of the European Charter of Local Self-Government is of great importance for countries achieving common goals and sharing common values. However, countries under study have problems and, in some cases, demonstrate non-compliance with provisions of Article 8. Such non-conformity as the endorsement of a mayor by the Flemish Government in Belgium, supervision with a view to expediency in Great Britain, and the tendency to overuse supervisory power in Poland are analysed. On the basis of research, the tendencies of administrative supervision of local authorities’ activities in selected European countries are described. Several recommendations for Ukraine as a country that had been granted the EU candidate status are formulated. Having emphasised its willingness to become a member of the European community, Ukraine should not only follow the best European practices but also avoid the mistakes of countries that have long-term experience in developing the local self-government institution. This project has received funding from the Research Council of Lithuania (LMTLT), agreement № P-PD-22-194Keywords: administrative supervision, decentralisation, legality, local authorities, local self-government
Procedia PDF Downloads 56637 Personality Moderates the Relation Between Mother´s Emotional Intelligence and Young Children´s Emotion Situation Knowledge
Authors: Natalia Alonso-Alberca, Ana I. Vergara
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From the very first years of their life, children are confronted with situations in which they need to deal with emotions. The family provides the first emotional experiences, and it is in the family context that children usually take their first steps towards acquiring emotion knowledge. Parents play a key role in this important task, helping their children develop emotional skills that they will need in challenging situations throughout their lives. Specifically, mothers are models imitated by their children. They create specific spatial and temporal contexts in which children learn about emotions, their causes, consequences, and complexity. This occurs not only through what mothers say or do directly to the child. Rather, it occurs, to a large extent, through the example that they set using their own emotional skills. The aim of the current study was to analyze how maternal abilities to perceive and to manage emotions influence children’s emotion knowledge, specifically, their emotion situation knowledge, taking into account the role played by the mother’s personality, the time spent together, and controlling the effect of age, sex and the child’s verbal abilities. Participants were 153 children from 4 schools in Spain, and their mothers. Children (41.8% girls)age range was 35 - 72 months. Mothers (N = 140) age (M = 38.7; R = 27-49). Twelve mothers had more than one child participating in the study. Main variables were the child´s emotion situation knowledge (ESK), measured by the Emotion Matching Task (EMT), and receptive language, using the Picture Vocabulary Test. Also, their mothers´ Emotional Intelligence (EI), through the Mayer, Salovey, Caruso Emotional Intelligence Test (MSCEIT) and personality, with The Big Five Inventory were analyzed. The results showed that the predictive power of maternal emotional skills on ESK was moderated by the mother’s personality, affecting both the direction and size of the relationships detected: low neuroticism and low openness to experience lead to a positive influence of maternal EI on children’s ESK, while high levels in these personality dimensions resulted in a negative influence on child´s ESK. The time that the mother and the child spend together was revealed as a positive predictor of this EK, while it did not moderate the influence of the mother's EI on child’s ESK. In light of the results, we can infer that maternal EI is linked to children’s emotional skills, though high level of maternal EI does not necessarily predict a greater degree of emotionknowledge in children, which seems rather to depend on specific personality profiles. The results of the current study indicate that a good level of maternal EI does not guarantee that children will learn the emotional skills that foster prosocial adaptation. Rather, EI must be accompanied by certain psychological characteristics (personality traits in this case).Keywords: emotional intelligence, emotion situation knowledge, mothers, personality, young children
Procedia PDF Downloads 124636 Binder-Free Porous Photocathode Based on Cuprous Oxide for High-Performing P-Type Dye-Sensitized Solar Cells
Authors: Marinela Miclau, Melinda Vajda, Nicolae Miclau, Daniel Ursu
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Characterized by a simple structure, easy and low cost fabrication, the dye-sensitized solar cell (DSSC) attracted the interest of the scientific community as an attractive alternative of conventional Si-based solar cells and thin-film solar cells. Over the past 20 years, the main efforts have attempted to enhance the efficiency of n-type DSSCs, the highest efficiency record of 14.30% was achieved using the co-sensitization of two metal-free organic dyes and Co (II/III) tris(phenanthroline)-based redox electrolyte. In the last years, the development of the efficient p-type DSSC has become a research focus owing to the fact that the concept of tandem solar cell was proposed as the solution to increase the power conversion efficiency. A promising alternative for the photocathodes of p-type DSSC, cuprous (Cu2O) and cupric (CuO) oxides have been investigated because of its nontoxic nature, low cost, high natural abundance, a good absorption coefficient for visible light and a higher dielectric constant than NiO. In case of p-type DSSC based on copper oxides with I3-/I- as redox mediator, the highest conversion efficiency of 0.42% (Cu2O) and 0.03% (CuO) has achieved. Towards the increase in the performance, we have fabricated and analyzed the performance of p-type DSSC prepared with the binder-free porous Cu2O photocathodes. Porous thin film could be an attractive alternative for DSSC because of their large surface areas which enable the efficient absorption of the dyes and light. We propose a simple and one-step hydrothermal method for the preparation of porous Cu2O thin film using copper substrate, cupric acetate and ethyl cellulose. The cubic structure of Cu2O has been determined by X-ray diffraction (XRD) and porous morphology of thin film was emphasized by Scanning Electron Microscope Inspect S (SEM). Optical and Mott-Schottky measurements attest of the high quality of the Cu2O thin film. The binder-free porous Cu2O photocathode has confirmed the excellent photovoltaic properties, the best value reported for p-type DSSC (1%) in similar conditions being reached.Keywords: cuprous oxide, dye-sensitized solar cell, hydrothermal method, porous photocathode
Procedia PDF Downloads 160635 Ecological Crisis: A Buddhist Approach
Authors: Jaharlal Debbarma
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The ecological crisis has become a threat to earth’s well-being. Man’s ambitious desire of wealth, pleasure, fame, longevity and happiness has extracted natural resources so vastly that it is unable to sustain a healthy life. Man’s greed for wealth and power has caused the setting up of vast factories which further created the problem of air, water and noise pollution, which have adversely affected both fauna and flora.It is no secret that man uses his inherent powers of reason, intelligence and creativity to change his environment for his advantage. But man is not aware that the moral force he himself creates brings about corresponding changes in his environment to his weal or woe whether he likes it or not. As we are facing the global warming and the nature’s gift such as air and water has been so drastically polluted with disastrous consequences that man seek for a ways and means to overcome all this pollution problem as his health and life sustainability has been threaten and that is where man try to question about the moral ethics and value.It is where Buddhist philosophy has been emphasized deeply which gives us hope for overcoming this entire problem as Buddha himself emphasized in eradicating human suffering and Buddhism is the strongest form of humanism we have. It helps us to learn to live with responsibility, compassion, and loving kindness.It teaches us to be mindful in our action and thought as the environment unites every human being. If we fail to save it we will perish. If we can rise to meet the need to all which ecology binds us - humans, other species, other everything will survive together.My paper will look into the theory of Dependent Origination (Pratītyasamutpāda), Buddhist understanding of suffering (collective suffering), and Non-violence (Ahimsa) and an effort will be made to provide a new vision to Buddhist ecological perspective. The above Buddhist philosophy will be applied to ethical values and belief systems of modern society. The challenge will be substantially to transform the modern individualistic and consumeristic values. The stress will be made on the interconnectedness of the nature and the relation between human and planetary sustainability. In a way environmental crisis will be referred to “spiritual crisis” as A. Gore (1992) has pointed out. The paper will also give important to global consciousness, as well as to self-actualization and self-fulfillment. In the words of Melvin McLeod “Only when we combine environmentalism with spiritual practice, will we find the tools to make the profound personal transformations needed to address the planetary crisis?”Keywords: dependent arising, collective ecological suffering, remediation, Buddhist approach
Procedia PDF Downloads 260634 Long-Term Economic-Ecological Assessment of Optimal Local Heat-Generating Technologies for the German Unrefurbished Residential Building Stock on the Quarter Level
Authors: M. A. Spielmann, L. Schebek
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In order to reach the long-term national climate goals of the German government for the building sector, substantial energetic measures have to be executed. Historically, those measures were primarily energetic efficiency measures at the buildings’ shells. Advanced technologies for the on-site generation of heat (or other types of energy) often are not feasible at this small spatial scale of a single building. Therefore, the present approach uses the spatially larger dimension of a quarter. The main focus of the present paper is the long-term economic-ecological assessment of available decentralized heat-generating (CHP power plants and electrical heat pumps) technologies at the quarter level for the German unrefurbished residential buildings. Three distinct terms have to be described methodologically: i) Quarter approach, ii) Economic assessment, iii) Ecological assessment. The quarter approach is used to enable synergies and scaling effects over a single-building. For the present study, generic quarters that are differentiated according to significant parameters concerning their heat demand are used. The core differentiation of those quarters is made by the construction time period of the buildings. The economic assessment as the second crucial parameter is executed with the following structure: Full costs are quantized for each technology combination and quarter. The investment costs are analyzed on an annual basis and are modeled with the acquisition of debt. Annuity loans are assumed. Consequently, for each generic quarter, an optimal technology combination for decentralized heat generation is provided in each year of the temporal boundaries (2016-2050). The ecological assessment elaborates for each technology combination and each quarter a Life Cycle assessment. The measured impact category hereby is GWP 100. The technology combinations for heat production can be therefore compared against each other concerning their long-term climatic impacts. Core results of the approach can be differentiated to an economic and ecological dimension. With an annual resolution, the investment and running costs of different energetic technology combinations are quantified. For each quarter an optimal technology combination for local heat supply and/or energetic refurbishment of the buildings within the quarter is provided. Coherently to the economic assessment, the climatic impacts of the technology combinations are quantized and compared against each other.Keywords: building sector, economic-ecological assessment, heat, LCA, quarter level
Procedia PDF Downloads 217633 Processes and Application of Casting Simulation and Its Software’s
Authors: Surinder Pal, Ajay Gupta, Johny Khajuria
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Casting simulation helps visualize mold filling and casting solidification; predict related defects like cold shut, shrinkage porosity and hard spots; and optimize the casting design to achieve the desired quality with high yield. Flow and solidification of molten metals are, however, a very complex phenomenon that is difficult to simulate correctly by conventional computational techniques, especially when the part geometry is intricate and the required inputs (like thermo-physical properties and heat transfer coefficients) are not available. Simulation software is based on the process of modeling a real phenomenon with a set of mathematical formulas. It is, essentially, a program that allows the user to observe an operation through simulation without actually performing that operation. Simulation software is used widely to design equipment so that the final product will be as close to design specs as possible without expensive in process modification. Simulation software with real-time response is often used in gaming, but it also has important industrial applications. When the penalty for improper operation is costly, such as airplane pilots, nuclear power plant operators, or chemical plant operators, a mockup of the actual control panel is connected to a real-time simulation of the physical response, giving valuable training experience without fear of a disastrous outcome. The all casting simulation software has own requirements, like magma cast has only best for crack simulation. The latest generation software Auto CAST developed at IIT Bombay provides a host of functions to support method engineers, including part thickness visualization, core design, multi-cavity mold design with common gating and feeding, application of various feed aids (feeder sleeves, chills, padding, etc.), simulation of mold filling and casting solidification, automatic optimization of feeders and gating driven by the desired quality level, and what-if cost analysis. IIT Bombay has developed a set of applications for the foundry industry to improve casting yield and quality. Casting simulation is a fast and efficient solution for process for advanced tool which is the result of more than 20 years of collaboration with major industrial partners and academic institutions around the world. In this paper the process of casting simulation is studied.Keywords: casting simulation software’s, simulation technique’s, casting simulation, processes
Procedia PDF Downloads 469632 The Antioxidant Gel Mask Supplies Of Bitter Melon's Extract ( Momordica charantia Linn.)
Authors: N. S. Risqina, G. Edijanti, P. S. Nurita, L. Endang, R. A. Siti, R. Tri
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Skin is an important and vital organs and also as a mirror of health and life. Facial skin care is one of the main emphasis to get the beautiful, healthy, and fresh skin. Potentially antioxidant phenolic compounds shows, antimutagen, antitumor, anti-inflammatory, and anti-cancer. Flavonoids are a group of polyphenolic compounds that have the nature of free radicals, inhibiting the oxidative and hydrolytic enzymes as well as anti-inflammatory. Bitter melon (Momordica charantia Linn) is a plant that contains flavonoids, and phenolic antioxidant activity. Bitter melon has strong antioxidant activity that can counteract the free radicals.These compounds can prevent free radicals that cause premature aging. Gel masks including depth cleansing is the cosmetics which work in depth and could raise the dead skin cells. Measurement of antioxidant activity of the extract and gel mask is done by using the immersion method of DPPH. IC50 value of ethanol extract of bitter melon fruit of 287.932 ppm. The preparation of gel mask bitter melon fruit extract, necessary to test the effectiveness of antioxidants using DPPH method is done by measuring the inhibition of DPPH and using UV spectrophotometer at the wavelength of maximum DPPH solution. Tests conducted at the beginning and end of the evaluation (day 0 and day 28). The purpose of this study is to determine the antioxidant activity of the bitter melon's extract and to determine the antioxidant activity of ethanol extract gel mask pare in varying concentrations, ie 1xIC100 (0.295%), 2xIC100 (0.590%) and 4xIC100 (1.180%). Evaluation of physical properties of the preparation on (Day-0,7,14,21, and 28) and evaluation of antioxidant activity (day 0 and 28). Data were analyzed using One Way ANOVA to determine differences in the physical properties of each formula. The statistical results showed that differences in the formula and storage time affects the adhesion, dispersive power, dry time and pH it is shown on a significant value of p <0.05, but longer storage does not affect the pH because the significance value p> 0,05. The antioxidant test showed that there are differences in antioxidant activity in all formulas. Measurement of antioxidant activity of bitter melon fruit extract gel mask on day 0 with a concentration of 0.295%, 0.590%, and 1.180%, respectively, are 124,209.277 ppm, ppm 83819.223 and 47323.592 ppm, whereas day 28 consecutive 130 411, 495 ppm, and 53239.806 95561.645 ppm ppm. The Conclusions drawn that there are antioxidant activity in preparation gel mask of bitter melon fruit extract. The antioxidant activity of bitter melon fruit extract gel mask on the day 0 with a concentration of 0.295%, 0.590%, and 1.180%, respectively, are 124,209.277 ppm, ppm 83819.223 and 47323.592 ppm, whereas on day 28 of antioxidant activity gel mask bitter melon fruit extract with a concentration of 0.295%, 0.590%, and 1.180% in succession, namely: 130,411.495 ppm, ppm 95561.645 and 53239.806 ppm.Keywords: antioxdant, bitter melon, gel mask, IC50
Procedia PDF Downloads 463631 Using Digital Innovations to Increase Awareness and Intent to Use Depo-Medroxy Progesterone Acetate-Subcutaneous Contraception among Women of Reproductive Age in Nigeria, Uganda, and Malawi
Authors: Oluwaseun Adeleke, Samuel O. Ikani, Fidelis Edet, Anthony Nwala, Mopelola Raji, Simeon Christian Chukwu
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Introduction: Digital innovations have been useful in supporting a client’s contraceptive user journey from awareness to method initiation. The concept of contraceptive self-care is being promoted globally as a means for achieving universal access to quality contraceptive care; however, information about this approach is limited. An important determinant of the scale of awareness is the message construct, choice of information channel, and an understanding of the socio-epidemiological dynamics within the target audience. Significant gains have been made recently in expanding the awareness base of DMPA-SC -a relatively new entrant into the family planning method mix. The cornerstone of this success is a multichannel promotion campaign themed Discover your Power (DYP). The DYP campaign combines content marketing across select social media platforms, chatbots, Cyber-IPC, Interactive Voice Response (IVR), and radio campaigns. Methodology: During implementation, the project monitored predefined metrics of awareness and intent, such as the number of persons reached with the messages, the number of impressions, and meaningful engagement (link-clicks). Metrics/indicators are extracted through native insight/analytics tools across the various platforms. The project also enlists community mobilizers (CMs) who go door-to-door and engage WRA to advertise DISC’s online presence and support them to engage with IVR, digital companion (chatbot), Facebook page, and DiscoverYourPower website. Results: The result showed that the digital platforms recorded 242 million impressions and reached 82 million users with key DMPA-SC self-injection messaging in the three countries. As many as 3.4 million persons engaged (liked, clicked, shared, or reposted) digital posts -an indication of intention. Conclusion: Digital solutions and innovations are gradually becoming the archetype for the advancement of the self-care agenda. Digital innovations can also be used to increase awareness and normalize contraceptive self-care behavior amongst women of reproductive age if they are made an integral part of reproductive health programming.Keywords: digital transformation, health systems, DMPA-SC, family planning, self-care
Procedia PDF Downloads 74630 A First Step towards Automatic Evolutionary for Gas Lifts Allocation Optimization
Authors: Younis Elhaddad, Alfonso Ortega
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Oil production by means of gas lift is a standard technique in oil production industry. To optimize the total amount of oil production in terms of the amount of gas injected is a key question in this domain. Different methods have been tested to propose a general methodology. Many of them apply well-known numerical methods. Some of them have taken into account the power of evolutionary approaches. Our goal is to provide the experts of the domain with a powerful automatic searching engine into which they can introduce their knowledge in a format close to the one used in their domain, and get solutions comprehensible in the same terms, as well. These proposals introduced in the genetic engine the most expressive formal models to represent the solutions to the problem. These algorithms have proven to be as effective as other genetic systems but more flexible and comfortable for the researcher although they usually require huge search spaces to justify their use due to the computational resources involved in the formal models. The first step to evaluate the viability of applying our approaches to this realm is to fully understand the domain and to select an instance of the problem (gas lift optimization) in which applying genetic approaches could seem promising. After analyzing the state of the art of this topic, we have decided to choose a previous work from the literature that faces the problem by means of numerical methods. This contribution includes details enough to be reproduced and complete data to be carefully analyzed. We have designed a classical, simple genetic algorithm just to try to get the same results and to understand the problem in depth. We could easily incorporate the well mathematical model, and the well data used by the authors and easily translate their mathematical model, to be numerically optimized, into a proper fitness function. We have analyzed the 100 curves they use in their experiment, similar results were observed, in addition, our system has automatically inferred an optimum total amount of injected gas for the field compatible with the addition of the optimum gas injected in each well by them. We have identified several constraints that could be interesting to incorporate to the optimization process but that could be difficult to numerically express. It could be interesting to automatically propose other mathematical models to fit both, individual well curves and also the behaviour of the complete field. All these facts and conclusions justify continuing exploring the viability of applying the approaches more sophisticated previously proposed by our research group.Keywords: evolutionary automatic programming, gas lift, genetic algorithms, oil production
Procedia PDF Downloads 157629 Antibacterial and Anti-Biofilm Activity of Vaccinium meridionale S. Pomace Extract Against Staphylococcus aureus, Escherichia coli and Salmonella Enterica
Authors: Carlos Y. Soto, Camila A. Lota, G. Astrid Garzón
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Bacterial biofilms cause an ongoing problem for food safety. They are formed when microorganisms aggregate to form a community that attaches to solid surfaces. Biofilms increase the resistance of pathogens to cleaning, disinfection and antibacterial products. This resistance gives rise to problems for human health, industry, and agriculture. At present, plant extracts rich in polyphenolics are being investigated as natural alternatives to degrade bacterial biofilms. The pomace of the tropical Berry Vaccinium meridionale S. contains high amounts of phenolic compounds. Therefore, in the current study, the antimicrobial and antibiofilm effects of extracts from the pomace of Vaccinium meridionale S. were tested on three foodborne pathogens: Enterohaemorrhagic Escherichia coli O157:H7 (ATCC®700728TM), Staphylococcus aureus subsp. aureus (ATCC® 6538TM), and Salmonella enterica serovar Enteritidis (ATCC® 13076TM). Microwave-assisted extraction was used to extract polyphenols with aqueous methanol (80% v/v) at a solid to solvent ratio of 1:10 (w/v) for 20 min. The magnetic stirring was set at 400 rpm, and the microwave power was adjusted to 400 W. The antimicrobial effect of the extract was assessed by determining the half maximal inhibitory concentration (IC50) against the three food poisoning pathogens at concentrations ranging from 50 to 2,850 μg gallic acid equivalents (GAE)/mL of the extract. Biofilm inhibition was assessed using a crystal violet assay applying the same range of concentration. Three replications of the experiments were carried out, and all analyses were run in triplicate. IC50 values were determined using the GraphPad Prism8® program. Significant differences (P<0.05) among means were identified using one-factor analysis of variance (ANOVA) and the post-hoc least significant difference (LSD) test using the Statgraphics plus program, version 2.1.There was significant difference among the mean IC50 values for the tested bacteria. The IC50 for S. aureus was 48 ± 9 μg GAE/mL, followed by 123 ± 49 μg GAE/mL for Salmonella and 376 ± 32 μg GAE/mL for E. coli. The percent inhibition of the extract on biofilm formation was significantly higher for S. aureus (85.8 0.3), followed by E. coli (74.5 1.0) and Salmonella (53.6 9.7). These findings suggest that polyphenolic extracts obtained from the pomace of V. meridionale S. might be used as natural antimicrobial and anti-biofilm natural agents, effective against S. aureus, E. coli and Salmonella enterica.Keywords: antibiofilm, antimicrobial, E. coli, S. aureus, salmonella, IC50, pomace, V. meridionale
Procedia PDF Downloads 55628 A Critical Discourse Analysis of Corporate Annual Reports in a Cross-Cultural Perspective: Views from Grammatical Metaphor and Systemic Functional Linguistics
Authors: Antonio Piga
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The study of language strategies in financial and corporate discourse has always been vital for understanding how companies manage to communicate effectively with a wider customer base and offers new perspectives on how companies interact with key stakeholders, not only to convey transparency and an image of trustworthiness, but also to create affiliation and attract investment. In the light of Systemic Functional Linguistics, the purpose of this study is to examine and analyse the annual reports of Asian and Western joint-stock companies involved in oil refining and power generation from the point of view of the functions and frequency of grammatical metaphors. More specifically, grammatical metaphor - through the lens of Critical Discourse Analysis (CDA) - is used as a theoretical tool for analysing a synchronic cross-cultural study of the communicative strategies adopted by Asian and Western companies to communicate social and environmental sustainability and showcase their ethical values, performance and competitiveness to local and global communities and key stakeholders. According to Systemic Functional Linguistics, grammatical metaphor can be divided into two broad areas: ideational and interpersonal. This study focuses on the first type, ideational grammatical metaphor (IGM), which includes de-adjectival and de-verbal nominalisation. The dominant and more effective grammatical tropes used by Asian and Western corporations in their annual reports were examined from both a qualitative and quantitative perspective. The aim was to categorise and explain how ideational grammatical metaphor is constructed cross-culturally and presented through structural language patterns involving re-mapping between semantics and lexico-grammatical features. The results show that although there seem to be more differences than similarities in terms of the categorisation of the ideational grammatical metaphors conceptualised in the two case studies analysed, there are more similarities than differences in terms of the occurrence, the congruence of process types and the role and function of IGM. Through the immediacy and essentialism of compacting and condensing information, IGM seems to be an important linguistic strategy adopted in the rhetoric of corporate annual reports, contributing to the ideologies and actions of companies to report and promote efficiency, profit and social and environmental sustainability, thus advocating the engagement and investment of key stakeholders.Keywords: corporate annual reports, cross-cultural perspective, ideational grammatical metaphor, rhetoric, systemic functional linguistics
Procedia PDF Downloads 30627 The Effect of Emotional Stimuli Related to Body Imbalance in Postural Control and the Phenomenological Experience of Young Healthy Adults
Authors: David Martinez-Pernia, Alvaro Rivera-Rei, Alejandro Troncoso, Gonzalo Forno, Andrea Slachevsky, David Huepe, Victoria Silva-Mack, Jorge Calderon, Mayte Vergara, Valentina Carrera
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Background: Recent theories in the field of emotions have taken the relevance of motor control beyond a system related to personal autonomy (walking, running, grooming), and integrate it into the emotional dimension. However, to our best knowledge, there are no studies that specifically investigate how emotional stimuli related to motor control modify emotional states in terms of postural control and phenomenological experience. Objective: The main aim of this work is to investigate the emotions produced by stimuli of bodily imbalance (neutral, pleasant and unpleasant) in the postural control and the phenomenological experience of young, healthy adults. Methodology: 46 healthy young people are shown emotional videos (neutral, pleasant, motor unpleasant, and non-motor unpleasant) related to the body imbalance. During the period of stimulation of each of the videos (60 seconds) the participant is standing on a force platform to collect temporal and spatial data of postural control. In addition, the electrophysiological activity of the heart and electrodermal activity is recorded. In relation to the two unpleasant conditions (motor versus non-motor), a phenomenological interview is carried out to collect the subjective experience of emotion and body perception. Results: Pleasant and unpleasant emotional videos have significant changes with respect to the neutral condition in terms of greater area, higher mean velocity, and greater mean frequency power on the anterior-posterior axis. The results obtained with respect to the electrodermal response was that the pleasurable and unpleasant conditions produced a significant increase in the phasic component with respect to the neutral condition. Regarding the electrophysiology of the heart, no significant change was found in any condition. Phenomenological experiences in the two unpleasant conditions differ in body perception and the emotional meaning of the experience. Conclusion: Emotional stimuli related to bodily imbalance produce changes in postural control, electrodermal activity, and phenomenological experience. This experimental setting could be relevant to be implemented in people with motor disorders (Parkinson, Stroke, TBI) to know how emotions affect motor control.Keywords: body imbalance stimuli, emotion, phenomenological experience, postural control
Procedia PDF Downloads 162626 A Simulation-Based Investigation of the Smooth-Wall, Radial Gravity Problem of Granular Flow through a Wedge-Shaped Hopper
Authors: A. F. Momin, D. V. Khakhar
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Granular materials consist of particulate particles found in nature and various industries that, due to gravity flow, behave macroscopically like liquids. A fundamental industrial unit operation is a hopper with inclined walls or a converging channel in which material flows downward under gravity and exits the storage bin through the bottom outlet. The simplest form of the flow corresponds to a wedge-shaped, quasi-two-dimensional geometry with smooth walls and radially directed gravitational force toward the apex of the wedge. These flows were examined using the Mohr-Coulomb criterion in the classic work of Savage (1965), while Ravi Prakash and Rao used the critical state theory (1988). The smooth-wall radial gravity (SWRG) wedge-shaped hopper is simulated using the discrete element method (DEM) to test existing theories. DEM simulations involve the solution of Newton's equations, taking particle-particle interactions into account to compute stress and velocity fields for the flow in the SWRG system. Our computational results are consistent with the predictions of Savage (1965) and Ravi Prakash and Rao (1988), except for the region near the exit, where both viscous and frictional effects are present. To further comprehend this behaviour, a parametric analysis is carried out to analyze the rheology of wedge-shaped hoppers by varying the orifice diameter, wedge angle, friction coefficient, and stiffness. The conclusion is that velocity increases as the flow rate increases but decreases as the wedge angle and friction coefficient increase. We observed no substantial changes in velocity due to varying stiffness. It is anticipated that stresses at the exit result from the transfer of momentum during particle collisions; for this reason, relationships between viscosity and shear rate are shown, and all data are collapsed into a single curve. In addition, it is demonstrated that viscosity and volume fraction exhibit power law correlations with the inertial number and that all the data collapse into a single curve. A continuum model for determining granular flows is presented using empirical correlations.Keywords: discrete element method, gravity flow, smooth-wall, wedge-shaped hoppers
Procedia PDF Downloads 76625 Systemic Functional Linguistics in the Rhetorical Strategies of Persuasion: A Longitudinal Study of Transitivity and Ergativity in the Rhetoric of Saras’ Sustainability Reports
Authors: Antonio Piga
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This study explores the correlation between Systemic Functional Linguistics (SFL) and Critical Discourse Analysis (CDA) as tools for analysing the evolution of rhetoric in the communicative strategies adopted in a company’s Reports on social and environmental responsibility. In more specific terms, transitivity and ergativity- concepts from Systemic Functional Linguistics (SFL) - through the lenses of CDA, are employed as a theoretical means for the analysis of a longitudinal study in the communicative strategies employed by Saras SpA pre- and during the Covid-19 pandemic crisis. Saras is an Italian joint-stock company operating in oil refining and power generation. The qualitative and quantitative linguistic analysis carried out through the use of Sketch Engine software aims to identify and explain how rhetoric - and ideology - is constructed and presented through language use in Saras SpA Sustainability Reports. Specific focus is given to communication strategies to local and global communities and stakeholders in the years immediately before and during the Covid-19 pandemic. The rationale behind the study lies in the fact that 2020 and 2021 have been among the most difficult years since the end of World War II. Lives were abruptly turned upside down by the pandemic, which had grave negative effects on people’s health and on the economy. The result has been a threefold crisis involving health, the economy and social tension, with the refining sector being one of the hardest hit, since the oil refining industry was one of the most affected industries due to the general reduction in mobility and oil consumption brought about by the virus-fighting measures. Emphasis is placed on the construction of rhetorical strategies pre- and during the pandemic crisis using the representational process of transitivity and ergativity (SFL), thus revealing the close relationship between the use language in terms of Social Actors and semantic roles of syntactic transformation on the one hand, and ideological assumptions on the other. The results show that linguistic decisions regarding transitivity and ergativity choices play a crucial role in how effective writing achieves its rhetorical objectives in terms of spreading and maintaining dominant and implicit ideologies and underlying persuasive actions, and that some ideological motivation is perpetuated – if not actually overtly or subtly strengthened - in social-environmental Reports issued in the midst of the Covid-19 pandemic crisis.Keywords: systemic functional linguistics, sustainability, critical discourse analysis, transitivity, ergativity
Procedia PDF Downloads 99624 Model-Based Diagnostics of Multiple Tooth Cracks in Spur Gears
Authors: Ahmed Saeed Mohamed, Sadok Sassi, Mohammad Roshun Paurobally
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Gears are important machine components that are widely used to transmit power and change speed in many rotating machines. Any breakdown of these vital components may cause severe disturbance to production and incur heavy financial losses. One of the most common causes of gear failure is the tooth fatigue crack. Early detection of teeth cracks is still a challenging task for engineers and maintenance personnel. So far, to analyze the vibration behavior of gears, different approaches have been tried based on theoretical developments, numerical simulations, or experimental investigations. The objective of this study was to develop a numerical model that could be used to simulate the effect of teeth cracks on the resulting vibrations and hence to permit early fault detection for gear transmission systems. Unlike the majority of published papers, where only one single crack has been considered, this work is more realistic, since it incorporates the possibility of multiple simultaneous cracks with different lengths. As cracks significantly alter the gear mesh stiffness, we performed a finite element analysis using SolidWorks software to determine the stiffness variation with respect to the angular position for different combinations of crack lengths. A simplified six degrees of freedom non-linear lumped parameter model of a one-stage gear system is proposed to study the vibration of a pair of spur gears, with and without tooth cracks. The model takes several physical properties into account, including variable gear mesh stiffness and the effect of friction, but ignores the lubrication effect. The vibration simulation results of the gearbox were obtained via Matlab and Simulink. The results were found to be consistent with the results from previously published works. The effect of one crack with different levels was studied and very similar changes in the total mesh stiffness and the vibration response, both were observed and compared to what has been found in previous studies. The effect of the crack length on various statistical time domain parameters was considered and the results show that these parameters were not equally sensitive to the crack percentage. Multiple cracks are introduced at different locations and the vibration response and the statistical parameters were obtained.Keywords: dynamic simulation, gear mesh stiffness, simultaneous tooth cracks, spur gear, vibration-based fault detection
Procedia PDF Downloads 202623 The Influence of Morphology and Interface Treatment on Organic 6,13-bis (triisopropylsilylethynyl)-Pentacene Field-Effect Transistors
Authors: Daniel Bülz, Franziska Lüttich, Sreetama Banerjee, Georgeta Salvan, Dietrich R. T. Zahn
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For the development of electronics, organic semiconductors are of great interest due to their adjustable optical and electrical properties. Especially for spintronic applications they are interesting because of their weak spin scattering, which leads to longer spin life times compared to inorganic semiconductors. It was shown that some organic materials change their resistance if an external magnetic field is applied. Pentacene is one of the materials which exhibit the so called photoinduced magnetoresistance which results in a modulation of photocurrent when varying the external magnetic field. Also the soluble derivate of pentacene, the 6,13-bis (triisopropylsilylethynyl)-pentacene (TIPS-pentacene) exhibits the same negative magnetoresistance. Aiming for simpler fabrication processes, in this work, we compare TIPS-pentacene organic field effect transistors (OFETs) made from solution with those fabricated by thermal evaporation. Because of the different processing, the TIPS-pentacene thin films exhibit different morphologies in terms of crystal size and homogeneity of the substrate coverage. On the other hand, the interface treatment is known to have a high influence on the threshold voltage, eliminating trap states of silicon oxide at the gate electrode and thereby changing the electrical switching response of the transistors. Therefore, we investigate the influence of interface treatment using octadecyltrichlorosilane (OTS) or using a simple cleaning procedure with acetone, ethanol, and deionized water. The transistors consist of a prestructured OFET substrates including gate, source, and drain electrodes, on top of which TIPS-pentacene dissolved in a mixture of tetralin and toluene is deposited by drop-, spray-, and spin-coating. Thereafter we keep the sample for one hour at a temperature of 60 °C. For the transistor fabrication by thermal evaporation the prestructured OFET substrates are also kept at a temperature of 60 °C during deposition with a rate of 0.3 nm/min and at a pressure below 10-6 mbar. The OFETs are characterized by means of optical microscopy in order to determine the overall quality of the sample, i.e. crystal size and coverage of the channel region. The output and transfer characteristics are measured in the dark and under illumination provided by a white light LED in the spectral range from 450 nm to 650 nm with a power density of (8±2) mW/cm2.Keywords: organic field effect transistors, solution processed, surface treatment, TIPS-pentacene
Procedia PDF Downloads 438622 Effect of Enzymatic Hydrolysis and Ultrasounds Pretreatments on Biogas Production from Corn Cob
Authors: N. Pérez-Rodríguez, D. García-Bernet, A. Torrado-Agrasar, J. M. Cruz, A. B. Moldes, J. M. Domínguez
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World economy is based on non-renewable, fossil fuels such as petroleum and natural gas, which entails its rapid depletion and environmental problems. In EU countries, the objective is that at least 20% of the total energy supplies in 2020 should be derived from renewable resources. Biogas, a product of anaerobic degradation of organic substrates, represents an attractive green alternative for meeting partial energy needs. Nowadays, trend to circular economy model involves efficiently use of residues by its transformation from waste to a new resource. In this sense, characteristics of agricultural residues (that are available in plenty, renewable, as well as eco-friendly) propitiate their valorisation as substrates for biogas production. Corn cob is a by-product obtained from maize processing representing 18 % of total maize mass. Corn cob importance lies in the high production of this cereal (more than 1 x 109 tons in 2014). Due to its lignocellulosic nature, corn cob contains three main polymers: cellulose, hemicellulose and lignin. Crystalline, highly ordered structures of cellulose and lignin hinders microbial attack and subsequent biogas production. For the optimal lignocellulose utilization and to enhance gas production in anaerobic digestion, materials are usually submitted to different pretreatment technologies. In the present work, enzymatic hydrolysis, ultrasounds and combination of both technologies were assayed as pretreatments of corn cob for biogas production. Enzymatic hydrolysis pretreatment was started by adding 0.044 U of Ultraflo® L feruloyl esterase per gram of dry corncob. Hydrolyses were carried out in 50 mM sodium-phosphate buffer pH 6.0 with a solid:liquid proportion of 1:10 (w/v), at 150 rpm, 40 ºC and darkness for 3 hours. Ultrasounds pretreatment was performed subjecting corn cob, in 50 mM sodium-phosphate buffer pH 6.0 with a solid: liquid proportion of 1:10 (w/v), at a power of 750W for 1 minute. In order to observe the effect of the combination of both pretreatments, some samples were initially sonicated and then they were enzymatically hydrolysed. In terms of methane production, anaerobic digestion of the corn cob pretreated by enzymatic hydrolysis was positive achieving 290 L CH4 kg MV-1 (compared with 267 L CH4 kg MV-1 obtained with untreated corn cob). Although the use of ultrasound as the only pretreatment resulted detrimentally (since gas production decreased to 244 L CH4 kg MV-1 after 44 days of anaerobic digestion), its combination with enzymatic hydrolysis was beneficial, reaching the highest value (300.9 L CH4 kg MV-1). Consequently, the combination of both pretreatments improved biogas production from corn cob.Keywords: biogas, corn cob, enzymatic hydrolysis, ultrasound
Procedia PDF Downloads 261621 Computational Fluid Dynamics Design and Analysis of Aerodynamic Drag Reduction Devices for a Mazda T3500 Truck
Authors: Basil Nkosilathi Dube, Wilson R. Nyemba, Panashe Mandevu
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In highway driving, over 50 percent of the power produced by the engine is used to overcome aerodynamic drag, which is a force that opposes a body’s motion through the air. Aerodynamic drag and thus fuel consumption increase rapidly at speeds above 90kph. It is desirable to minimize fuel consumption. Aerodynamic drag reduction in highway driving is the best approach to minimize fuel consumption and to reduce the negative impacts of greenhouse gas emissions on the natural environment. Fuel economy is the ultimate concern of automotive development. This study aims to design and analyze drag-reducing devices for a Mazda T3500 truck, namely, the cab roof and rear (trailer tail) fairings. The aerodynamic effects of adding these append devices were subsequently investigated. To accomplish this, two 3D CAD models of the Mazda truck were designed using the Design Modeler. One, with these, append devices and the other without. The models were exported to ANSYS Fluent for computational fluid dynamics analysis, no wind tunnel tests were performed. A fine mesh with more than 10 million cells was applied in the discretization of the models. The realizable k-ε turbulence model with enhanced wall treatment was used to solve the Reynold’s Averaged Navier-Stokes (RANS) equation. In order to simulate the highway driving conditions, the tests were simulated with a speed of 100 km/h. The effects of these devices were also investigated for low-speed driving. The drag coefficients for both models were obtained from the numerical calculations. By adding the cab roof and rear (trailer tail) fairings, the simulations show a significant reduction in aerodynamic drag at a higher speed. The results show that the greatest drag reduction is obtained when both devices are used. Visuals from post-processing show that the rear fairing minimized the low-pressure region at the rear of the trailer when moving at highway speed. The rear fairing achieved this by streamlining the turbulent airflow, thereby delaying airflow separation. For lower speeds, there were no significant differences in drag coefficients for both models (original and modified). The results show that these devices can be adopted for improving the aerodynamic efficiency of the Mazda T3500 truck at highway speeds.Keywords: aerodynamic drag, computation fluid dynamics, fluent, fuel consumption
Procedia PDF Downloads 127620 Investigation of Mechanical and Tribological Property of Graphene Reinforced SS-316L Matrix Composite Prepared by Selective Laser Melting
Authors: Ajay Mandal, Jitendar Kumar Tiwari, N. Sathish, A. K. Srivastava
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A fundamental investigation is performed on the development of graphene (Gr) reinforced stainless steel 316L (SS 316L) metal matrix composite via selective laser melting (SLM) in order to improve specific strength and wear resistance property of SS 316L. Firstly, SS 316L powder and graphene were mixed in a fixed ratio using low energy planetary ball milling. The milled powder is then subjected to the SLM process to fabricate composite samples at a laser power of 320 W and exposure time of 100 µs. The prepared composite was mechanically tested (hardness and tensile test) at ambient temperature, and obtained results indicate that the properties of the composite increased significantly with the addition of 0.2 wt. % Gr. Increment of about 25% (from 194 to 242 HV) and 70% (from 502 to 850 MPa) is obtained in hardness and yield strength of composite, respectively. Raman mapping and XRD were performed to see the distribution of Gr in the matrix and its effect on the formation of carbide, respectively. Results of Raman mapping show the uniform distribution of graphene inside the matrix. Electron back scatter diffraction (EBSD) map of the prepared composite was analyzed under FESEM in order to understand the microstructure and grain orientation. Due to thermal gradient, elongated grains were observed along the building direction, and grains get finer with the addition of Gr. Most of the mechanical components are subjected to several types of wear conditions. Therefore, it is very necessary to improve the wear property of the component, and hence apart from strength and hardness, a tribological property of composite was also measured under dry sliding condition. Solid lubrication property of Gr plays an important role during the sliding process due to which the wear rate of composite reduces up to 58%. Also, the surface roughness of worn surface reduces up to 70% as measured by 3D surface profilometry. Finally, it can be concluded that SLM is an efficient method of fabricating cutting edge metal matrix nano-composite having Gr like reinforcement, which was very difficult to fabricate through conventional manufacturing techniques. Prepared composite has superior mechanical and tribological properties and can be used for a wide variety of engineering applications. However, due to the unavailability of a considerable amount of literature in a similar domain, more experimental works need to perform, such as thermal property analysis, and is a part of ongoing study.Keywords: selective laser melting, graphene, composite, mechanical property, tribological property
Procedia PDF Downloads 133619 Sports Activities and their Impact on Disability
Authors: Ajved Ahmed
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This research paper explores the intricate relationship between sports activities and disability, aiming to shed light on the multifaceted impacts of sports participation on individuals with disabilities. As the world grapples with the challenges posed by the growing population of people with disabilities, understanding the role of sports in their lives becomes increasingly important. The paper begins by providing a comprehensive overview of the diverse forms of disabilities, emphasizing the wide spectrum of physical, sensory, and cognitive impairments. It then delves into the benefits of sports activities for individuals with disabilities, highlighting the profound physical, psychological, and social advantages that engagement in sports can offer. These benefits encompass improved physical fitness, enhanced self-esteem and mental well-being, increased social integration, and a sense of empowerment and independence. Furthermore, the paper examines the barriers and challenges that individuals with disabilities often encounter when attempting to participate in sports activities, ranging from inaccessible facilities to societal prejudices and stereotypes. It underscores the critical role of inclusive sports programs, adaptive equipment, and policy initiatives in overcoming these barriers and fostering an environment where everyone can enjoy the benefits of sports. Through a comprehensive review of existing research and case studies, the paper also explores specific sports and their suitability for various types of disabilities. It discusses adapted sports like wheelchair basketball, blind soccer, and para-swimming, showcasing how these tailored activities not only accommodate disabilities but also promote excellence and competition at the highest levels. Additionally, the research paper delves into the economic and societal implications of increased sports participation among individuals with disabilities. It explores the potential for greater inclusion in the workforce, reduced healthcare costs, and the fostering of a more inclusive and accepting society. This research paper underscores the profound impact of sports activities on individuals with disabilities, highlighting their potential to improve physical health, mental well-being, and social integration. It calls for continued efforts to break down barriers and promote inclusive sports programs to ensure that everyone, regardless of their abilities, can access the transformative power of sports. Ultimately, this study contributes to a broader understanding of disability and sports, emphasizing the importance of inclusivity and accessibility in creating a more equitable and healthier society.Keywords: sports and health, sports and disability, curing disability through sports, health benefits of sports
Procedia PDF Downloads 54618 Ribotaxa: Combined Approaches for Taxonomic Resolution Down to the Species Level from Metagenomics Data Revealing Novelties
Authors: Oshma Chakoory, Sophie Comtet-Marre, Pierre Peyret
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Metagenomic classifiers are widely used for the taxonomic profiling of metagenomic data and estimation of taxa relative abundance. Small subunit rRNA genes are nowadays a gold standard for the phylogenetic resolution of complex microbial communities, although the power of this marker comes down to its use as full-length. We benchmarked the performance and accuracy of rRNA-specialized versus general-purpose read mappers, reference-targeted assemblers and taxonomic classifiers. We then built a pipeline called RiboTaxa to generate a highly sensitive and specific metataxonomic approach. Using metagenomics data, RiboTaxa gave the best results compared to other tools (Kraken2, Centrifuge (1), METAXA2 (2), PhyloFlash (3)) with precise taxonomic identification and relative abundance description, giving no false positive detection. Using real datasets from various environments (ocean, soil, human gut) and from different approaches (metagenomics and gene capture by hybridization), RiboTaxa revealed microbial novelties not seen by current bioinformatics analysis opening new biological perspectives in human and environmental health. In a study focused on corals’ health involving 20 metagenomic samples (4), an affiliation of prokaryotes was limited to the family level with Endozoicomonadaceae characterising healthy octocoral tissue. RiboTaxa highlighted 2 species of uncultured Endozoicomonas which were dominant in the healthy tissue. Both species belonged to a genus not yet described, opening new research perspectives on corals’ health. Applied to metagenomics data from a study on human gut and extreme longevity (5), RiboTaxa detected the presence of an uncultured archaeon in semi-supercentenarians (aged 105 to 109 years) highlighting an archaeal genus, not yet described, and 3 uncultured species belonging to the Enorma genus that could be species of interest participating in the longevity process. RiboTaxa is user-friendly, rapid, allowing microbiota structure description from any environment and the results can be easily interpreted. This software is freely available at https://github.com/oschakoory/RiboTaxa under the GNU Affero General Public License 3.0.Keywords: metagenomics profiling, microbial diversity, SSU rRNA genes, full-length phylogenetic marker
Procedia PDF Downloads 107617 The Sources of Anti-Immigrant Sentiments in Russia
Authors: Anya Glikman, Anastasia Gorodzeisky
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Since the late 1990th labor immigration and its consequences on the society have become one of the most frequently discussed and debated issues in Russia. Social scientists point that the negative attitudes towards immigrants among Russian majority population is widespread, and their level, at least, twice as high as their level in most other European countries. Moreover, recent study by Gorodzeisky, Glikman and Maskyleison (2014) demonstrates that the two sets of individual level predictors of anti-foreigner sentiment – socio-economic status and conservative views and ideologies – that have been repeatedly proved in research in Western countries are not effective in predicting of anti-foreigner sentiment in Post-Socialist Russia. Apparently, the social mechanisms underlying anti-foreigner sentiment in Western countries, which are characterized by stable regimes and relatively long immigration histories, do not play a significant role in the explanation of anti-foreigner sentiment in Post-Socialist Russia. The present study aims to examine alternative possible sources of anti-foreigner sentiment in Russia while controlling for socio-economic position of individuals and conservative views. More specifically, following the research literature on the topic worldwide, we aim to examine whether and to what extent human values (such as tradition, universalism, safety and power), ethnic residential segregation, fear of crime and exposure to mass media affect anti-foreigner sentiments in Russia. To do so, we estimate a series of multivariate regression equations using the data obtained from 2012 European Social Survey. The national representative sample consists of 2337 Russian born respondents. Descriptive results reveal that about 60% percent of Russians view the impact of immigrants on the country in negative terms. Further preliminary analysis show that anti-foreigner sentiments are associated with exposer to mass media as well as with fear of crime. Specifically, respondents who devoted more time watching news on TV channels and respondents who express higher levels of fear of crime tend to report higher levels of anti-immigrants sentiments. The findings would be discussed in light of sociological perspective and the context of Russian society.Keywords: anti-immigrant sentiments, fear of crime, human values, mass media, Russia
Procedia PDF Downloads 449616 Data Clustering Algorithm Based on Multi-Objective Periodic Bacterial Foraging Optimization with Two Learning Archives
Authors: Chen Guo, Heng Tang, Ben Niu
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Clustering splits objects into different groups based on similarity, making the objects have higher similarity in the same group and lower similarity in different groups. Thus, clustering can be treated as an optimization problem to maximize the intra-cluster similarity or inter-cluster dissimilarity. In real-world applications, the datasets often have some complex characteristics: sparse, overlap, high dimensionality, etc. When facing these datasets, simultaneously optimizing two or more objectives can obtain better clustering results than optimizing one objective. However, except for the objectives weighting methods, traditional clustering approaches have difficulty in solving multi-objective data clustering problems. Due to this, evolutionary multi-objective optimization algorithms are investigated by researchers to optimize multiple clustering objectives. In this paper, the Data Clustering algorithm based on Multi-objective Periodic Bacterial Foraging Optimization with two Learning Archives (DC-MPBFOLA) is proposed. Specifically, first, to reduce the high computing complexity of the original BFO, periodic BFO is employed as the basic algorithmic framework. Then transfer the periodic BFO into a multi-objective type. Second, two learning strategies are proposed based on the two learning archives to guide the bacterial swarm to move in a better direction. On the one hand, the global best is selected from the global learning archive according to the convergence index and diversity index. On the other hand, the personal best is selected from the personal learning archive according to the sum of weighted objectives. According to the aforementioned learning strategies, a chemotaxis operation is designed. Third, an elite learning strategy is designed to provide fresh power to the objects in two learning archives. When the objects in these two archives do not change for two consecutive times, randomly initializing one dimension of objects can prevent the proposed algorithm from falling into local optima. Fourth, to validate the performance of the proposed algorithm, DC-MPBFOLA is compared with four state-of-art evolutionary multi-objective optimization algorithms and one classical clustering algorithm on evaluation indexes of datasets. To further verify the effectiveness and feasibility of designed strategies in DC-MPBFOLA, variants of DC-MPBFOLA are also proposed. Experimental results demonstrate that DC-MPBFOLA outperforms its competitors regarding all evaluation indexes and clustering partitions. These results also indicate that the designed strategies positively influence the performance improvement of the original BFO.Keywords: data clustering, multi-objective optimization, bacterial foraging optimization, learning archives
Procedia PDF Downloads 128615 Acerola and Orange By-Products as Sources of Bioactive Compounds for Probiotic Fermented Milks
Authors: Tatyane Lopes de Freitas, Antonio Diogo S. Vieira, Susana Marta Isay Saad, Maria Ines Genovese
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The fruit processing industries generate a large volume of residues to produce juices, pulps, and jams. These residues, or by-products, consisting of peels, seeds, and pulps, are routinely discarded. Fruits are rich in bioactive compounds, including polyphenols, which have positive effects on health. Dry residues from two fruits, acerola (M. emarginata D. C.) and orange (C. sinensis), were characterized in relation to contents of ascorbic acid, minerals, total dietary fibers, moisture, ash, lipids, proteins, and carbohydrates, and also high performance liquid chromatographic profile of flavonoids, total polyphenols and proanthocyanidins contents, and antioxidant capacity by three different methods (Ferric reducing antioxidant power assay-FRAP, Oxygen Radical Absorbance Capacity-ORAC, 1,1-diphenyl-2-picrylhydrazil (DPPH) radical scavenging activity). Acerola by-products presented the highest acid ascorbic content (605 mg/100 g), and better antioxidant capacity than orange by-products. The dry residues from acerola demonstrated high contents of proanthocyanidins (617 µg CE/g) and total polyphenols (2525 mg gallic acid equivalents - GAE/100 g). Both presented high total dietary fiber (above 60%) and protein contents (acerola: 10.4%; orange: 9.9%), and reduced fat content (acerola: 1.6%; orange: 2.6%). Both residues showed high levels of potassium, calcium, and magnesium, and were considered sources of these minerals. With acerola by-product, four formulations of probiotics fermented milks were produced: F0 (without the addition of acerola residue (AR)), F2 (2% AR), F5 (5% AR) and F10 (10% AR). The physicochemical characteristics of the fermented milks throughout of storage were investigated, as well as the impact of in vitro simulated gastrointestinal conditions on flavonoids and probiotics. The microorganisms analyzed maintained their populations around 8 log CFU/g during storage. After the gastric phase of the simulated digestion, the populations decreased, and after the enteric phase, no colonies were detected. On the other hand, the flavonoids increased after the gastric phase, maintaining or suffering small decrease after enteric phase. Acerola by-products powder is a valuable ingredient to be used in functional foods because is rich in vitamin C, fibers and flavonoids. These flavonoids appear to be highly resistant to the acids and salts of digestion.Keywords: acerola, orange, by-products, fermented milk
Procedia PDF Downloads 124614 Increased Efficiency during Oxygen Carrier Aided Combustion of Municipal Solid Waste in an Industrial Scaled Circulating Fluidized Bed-Boiler
Authors: Angelica Corcoran, Fredrik Lind, Pavleta Knutsson, Henrik Thunman
Abstract:
Solid waste volumes are at current predominately deposited on landfill. Furthermore, the impending climate change requires new solutions for a sustainable future energy mix. Currently, solid waste is globally utilized to small extent as fuel during combustion for heat and power production. Due to its variable composition and size, solid waste is considered difficult to combust and requires a technology with high fuel flexibility. One of the commercial technologies used for combustion of such difficult fuels is circulating fluidized beds (CFB). In a CFB boiler, fine particles of a solid material are used as 'bed material', which is accelerated by the incoming combustion air that causes the bed material to fluidize. The chosen bed material has conventionally been silica sand with the main purpose of being a heat carrier, as it transfers heat released by the combustion to the heat-transfer surfaces. However, the release of volatile compounds occurs rapidly in comparison with the lateral mixing in the combustion chamber. To ensure complete combustion a surplus of air is introduced, which decreases the total efficiency of the boiler. In recent years, the concept of partly or entirely replacing the silica sand with an oxygen carrier as bed material has been developed. By introducing an oxygen carrier to the combustion chamber, combustion can be spread out both temporally and spatially in the boiler. Specifically, the oxygen carrier can take up oxygen from the combustion air where it is in abundance and release it to combustible gases where oxygen is in deficit. The concept is referred to as oxygen carrier aided combustion (OCAC) where the natural ore ilmenite (FeTiO3) has been the oxygen carrier used. The authors have validated the oxygen buffering ability of ilmenite during combustion of biomass in Chalmers 12-MWth CFB boiler in previous publications. Furthermore, the concept has been demonstrated on full industrial scale during combustion of municipal solid waste (MSW) in E.ON’s 75 MWth CFB boiler. The experimental campaigns have showed increased mass transfer of oxygen inside the boiler when combustion both biomass and MSW. As a result, a higher degree of burnout is achieved inside the combustion chamber and the plant can be operated at a lower surplus of air. Moreover, the buffer of oxygen provided by the oxygen carrier makes the system less sensitive to disruptions in operation. In conclusion, combusting difficult fuels with OCAC results in higher operation stability and an increase in boiler efficiency.Keywords: OCAC, ilmenite, combustion, CFB
Procedia PDF Downloads 233