Search results for: electrical arc furnace dust
1177 Digital Subsistence of Cultural Heritage: Digital Media as a New Dimension of Cultural Ecology
Authors: Dan Luo
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With the climate change can exacerbate exposure of cultural heritage to climatic stressors, scholars pin their hope on digital technology can help the site avoid surprises. Virtual museum has been regarded as a highly effective technology that enables people to gain enjoyable visiting experience and immersive information about cultural heritage. The technology clearly reproduces the images of the tangible cultural heritage, and the aesthetic experience created by new media helps consumers escape from the realistic environment full of uncertainty. The new cultural anchor has appeared outside the cultural sites. This article synthesizes the international literature on the virtual museum by developing diagrams of Citespace focusing on the tangible cultural heritage and the alarmingly situation has emerged in the process of resolving climate change: (1) Digital collections are the different cultural assets for public. (2) The media ecology change people ways of thinking and meeting style of cultural heritage. (3) Cultural heritage may live forever in the digital world. This article provides a typical practice information to manage cultural heritage in a changing climate—the Dunhuang Mogao Grottoes in the far northwest of China, which is a worldwide cultural heritage site famous for its remarkable and sumptuous murals. This monument is a typical synthesis of art containing 735 Buddhist temples, which was listed by UNESCO as one of the World Cultural Heritage sites. The caves contain some extraordinary examples of Buddhist art spanning a period of 1,000 years - the architectural form, the sculptures in the caves, and the murals on the walls, all together constitute a wonderful aesthetic experience. Unfortunately, this magnificent treasure cave has been threatened by increasingly frequent dust storms and precipitation. The Dunhuang Academy has been using digital technology since the last century to preserve these immovable cultural heritages, especially the murals in the caves. And then, Dunhuang culture has become a new media culture after introduce the art to the world audience through exhibitions, VR, video, etc. The paper chooses qualitative research method that used Nvivo software to encode the collected material to answer this question. The author paid close attention to the survey in Dunhuang City, including participated in 10 exhibition and 20 salons that are Dunhuang-themed on network. What’s more, 308 visitors were interviewed who are fans of the art and have experienced Dunhuang culture online(6-75 years).These interviewees have been exposed to Dunhuang culture through different media, and they are acutely aware of the threat to this cultural heritage. The conclusion is that the unique halo of the cultural heritage was always emphasized, and digital media breeds twin brothers of cultural heritage. In addition, the digital media make it possible for cultural heritage to reintegrate into the daily life of the masses. Visitors gain the opportunity to imitate the mural figures through enlarged or emphasized images but also lose the perspective of understanding the whole cultural life. New media construct a new life aesthetics apart from the Authorized heritage discourse.Keywords: cultural ecology, digital twins, life aesthetics, media
Procedia PDF Downloads 811176 Modern Pedagogy Techniques for DC Motor Speed Control
Authors: Rajesh Kumar, Roopali Dogra, Puneet Aggarwal
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Based on a survey conducted for second and third year students of the electrical engineering department at Maharishi Markandeshwar University, India, it was found that around 92% of students felt that it would be better to introduce a virtual environment for laboratory experiments. Hence, a need was felt to perform modern pedagogy techniques for students which consist of a virtual environment using MATLAB/Simulink. In this paper, a virtual environment for the speed control of a DC motor is performed using MATLAB/Simulink. The various speed control methods for the DC motor include the field resistance control method and armature voltage control method. The performance analysis of the DC motor is hence analyzed.Keywords: DC Motor, field control, pedagogy techniques, speed control, virtual environment, voltage control
Procedia PDF Downloads 4401175 Design and Development of Automatic Onion Harvester
Authors: P. Revathi, T. Mrunalini, K. Padma Priya, P. Ramya, R. Saranya
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During the tough times of covid, those people who were hospitalized found it difficult to always convey what they wanted to or needed to the attendee. Sometimes the attendees might also not be there. In that case, the patients can use simple hand gestures to control electrical appliances (like its set it for a zero watts bulb)and three other gestures for voice note intimation. In this AI-based hand recognition project, NodeMCU is used for the control action of the relay, and it is connected to the firebase for storing the value in the cloud and is interfaced with the python code via raspberry pi. For three hand gestures, a voice clip is added for intimation to the attendee. This is done with the help of Google’s text to speech and the inbuilt audio file option in the raspberry pi 4. All the 5 gestures will be detected when shown with their hands via a webcam which is placed for gesture detection. A personal computer is used for displaying the gestures and for running the code in the raspberry pi imager.Keywords: onion harvesting, automatic pluging, camera, raspberry pi
Procedia PDF Downloads 1961174 Sustainable Underground Structures Through Soil-Driven Bio-Protection of Concrete
Authors: Abdurahim Abogdera, Omar Hamza, David Elliott
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The soil bacteria can be affected by some factors such as pH, calcium ions and Electrical conductivity. Fresh concrete has high pH value, which is between 11 and 13 and these values will be prevented the bacteria to produce CO₂ to participate with Calcium ions that released from the concrete to get calcite. In this study we replaced 15% and 25% of cement with Fly ash as the fly ash reduce the value of the pH at the concrete. The main goal of this study was investigated whether bacteria can be used on the soil rather than in the concrete to avoid the challenges and limitations of containing bacteria inside the concrete. This was achieved by incubating cracked cement mortar specimens into fully saturated sterilized and non-sterilized soil. The crack sealing developed in the specimens during the incubation period in both soil conditions were evaluated and compared. Visual inspection, water absorption test, scanning electron microscopy (SEM), and Energy Dispersive X-ray (EDX) were conducted to evaluate the healing process.Keywords: pH, calcium ions, MICP, salinity
Procedia PDF Downloads 1121173 Fault Location Identification in High Voltage Transmission Lines
Authors: Khaled M. El Naggar
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This paper introduces a digital method for fault section identification in transmission lines. The method uses digital set of the measured short circuit current to locate faults in electrical power systems. The digitized current is used to construct a set of overdetermined system of equations. The problem is then constructed and solved using the proposed digital optimization technique to find the fault distance. The proposed optimization methodology is an application of simulated annealing optimization technique. The method is tested using practical case study to evaluate the proposed method. The accurate results obtained show that the algorithm can be used as a powerful tool in the area of power system protection.Keywords: optimization, estimation, faults, measurement, high voltage, simulated annealing
Procedia PDF Downloads 3911172 Arc Plasma Thermochemical Preparation of Coal to Effective Combustion in Thermal Power Plants
Authors: Vladimir Messerle, Alexandr Ustimenko, Oleg Lavrichshev
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This work presents plasma technology for solid fuel ignition and combustion. Plasma activation promotes more effective and environmentally friendly low-rank coal ignition and combustion. To realise this technology at coal fired power plants plasma-fuel systems (PFS) were developed. PFS improve efficiency of power coals combustion and decrease harmful emission. PFS is pulverized coal burner equipped with arc plasma torch. Plasma torch is the main element of the PFS. Plasma forming gas is air. It is blown through the electrodes forming plasma flame. Temperature of this flame is varied from 5000 to 6000 K. Plasma torch power is varied from 100 to 350 kW and geometrical sizes are the following: the height is 0.4-0.5 m and diameter is 0.2-0.25 m. The base of the PFS technology is plasma thermochemical preparation of coal for burning. It consists of heating of the pulverized coal and air mixture by arc plasma up to temperature of coal volatiles release and char carbon partial gasification. In the PFS coal-air mixture is deficient in oxygen and carbon is oxidised mainly to carbon monoxide. As a result, at the PFS exit a highly reactive mixture is formed of combustible gases and partially burned char particles, together with products of combustion, while the temperature of the gaseous mixture is around 1300 K. Further mixing with the air promotes intensive ignition and complete combustion of the prepared fuel. PFS have been tested for boilers start up and pulverized coal flame stabilization in different countries at power boilers of 75 to 950 t/h steam productivity. They were equipped with different types of pulverized coal burners (direct flow, muffle and swirl burners). At PFS testing power coals of all ranks (lignite, bituminous, anthracite and their mixtures) were incinerated. Volatile content of them was from 4 to 50%, ash varied from 15 to 48% and heat of combustion was from 1600 to 6000 kcal/kg. To show the advantages of the plasma technology before conventional technologies of coal combustion numerical investigation of plasma ignition, gasification and thermochemical preparation of a pulverized coal for incineration in an experimental furnace with heat capacity of 3 MW was fulfilled. Two computer-codes were used for the research. The computer simulation experiments were conducted for low-rank bituminous coal of 44% ash content. The boiler operation has been studied at the conventional mode of combustion and with arc plasma activation of coal combustion. The experiments and computer simulation showed ecological efficiency of the plasma technology. When a plasma torch operates in the regime of plasma stabilization of pulverized coal flame, NOX emission is reduced twice and amount of unburned carbon is reduced four times. Acknowledgement: This work was supported by Ministry of Education and Science of the Republic of Kazakhstan and Ministry of Education and Science of the Russian Federation (Agreement on grant No. 14.613.21.0005, project RFMEFI61314X0005).Keywords: coal, ignition, plasma-fuel system, plasma torch, thermal power plant
Procedia PDF Downloads 2771171 Road Map to Health: Palestinian Workers in Israel's Construction Sector
Authors: Maya de Vries Kedem, Abir Jubran, Diana Baron
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Employment in Israel offers Palestinian workers an income double what they can earn in the West Bank. The need to support their families leads many educated Palestinians to forgo finding work in their profession in the Palestinian Authority and instead look for employment in those sectors open to them in Israel, particularly the construction, agriculture, and industry sectors. The International Labor Organization estimated that about 1,200 workers in Israel die every year because of occupational diseases (diseases caused by working conditions). Construction workers in Israel are constantly exposed to dust, noise, chemical materials, and work in awkward postures, which require prolonged bending, repetitive motion, and other risk factors that can lead to illnesses and death. Occupational health is vastly neglected in Israel and construction workers are particularly at risk . As of June 2022, the Israeli quota in the construction sector for Palestinian workers stood at 80,000. Kav LaOved released a new study on the state of occupational health among Palestinian workers employed in construction in Israel. The study Roadmap to Health: Palestinian Workers in Israel's Construction Sector reviews the extent to which the health of Palestinian workers is protected at work in Israel. The report includes analysis of a survey administered to 256 workers as well as interviews with 10 workers and with 5 Israeli occupational health experts. Report highlights: • Among survey respondents, 63.9% stated that safety procedures to protect their health are rarely followed in their workplace (e.g., taking breaks, using protective gear, following restrictions on lifting heavy items, and having inspectors regularly on site to monitor safety). • All 256 Palestinian workers who participated to the survey said that their health has been directly or indirectly harmed by working in Israel and reported suffering from the following problems: orthopedic problems such as joint, hand, leg or knee problems (100%); headaches (75%); back problems (36.3%); eye problems (23.8%); breathing problems (17.6%); chronic pain (14.8%); heart problems (7.8%); and skin problems (3.5%). • Workers who are injured or do not feel well often continue working for fear of losing their payment for that day. About half of the 256 survey respondents reported that they pay brokerage fees to find an employer with a work permit, often paying between 2,000 and 3,000 NIS per month. “I have an obligation—I pay about NIS 120 a day for my permit, [and] I have to pay for it whether I work or not" a worker said. • Most Palestinian construction workers suffer from stress and mental health problems. Workers pointed to several issues that greatly affect their mood and mental state: daily crossings at crowded checkpoints where workers stand for hours; lack of sleep due to leaving home daily at 3:00-3:30 am; commuting two to four hours to work in each direction; and abusive work environments. A worker told KLO that the sight of thousands of workers standing together at the checkpoint causes “high blood pressure and the feeling that you are going to be squeezed.” Another said, “I felt that my bones would break.” In the survey workers reported suffering from insomnia (70.1%), breathing difficulties (35.8%), chest pressure (27.6%), or rapid pulse rate (12.2%).Keywords: construction sector, palestinian workers, occupational health, Israel, occupation
Procedia PDF Downloads 871170 Powering Pacemakers from Heart Pressure Variation with Piezoelectric Energy Harvesters
Authors: A. Mathieu, B. Aubry, E. Chhim, M. Jobe, M. Arnaud
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Present project consists in a study and a development of piezoelectric devices for supplying power to new generation pacemakers. They are miniaturized leadless implants without battery placed directly in right ventricle. Amongst different acceptable energy sources in cardiac environment, we choose the solution of a device based on conversion of the energy produced by pressure variation inside the heart into electrical energy. The proposed energy harvesters can meet the power requirements of pacemakers, and can be a good solution to solve the problem of regular surgical operation. With further development, proposed device should provide enough energy to allow pacemakers autonomy, and could be good candidate for next pacemaker generation.Keywords: energy harvester, heart, leadless pacemaker, piezoelectric cells, pressure variation
Procedia PDF Downloads 4441169 Field Experience with Sweep Frequency Response Analysis for Power Transformer Diagnosis
Authors: Ambuj Kumar, Sunil Kumar Singh, Shrikant Singh, Zakir Husain, R. K. Jarial
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Sweep frequency response analysis has been turning out a powerful tool for investigation of mechanical as well as electrical integration of transformers. In this paper various aspect of practical application of SFRA has been studied. Open circuit and short circuit measurement were done on different phases of high voltage and low voltage winding. A case study was presented for the transformer of rating 31.5 MVA for various frequency ranges. A clear picture was presented for sub- frequency ranges for HV as well as LV winding. The main motive of work is to investigate high voltage short circuit response. The theoretical concept about SFRA responses is validated with expert system software results.Keywords: transformer winding, SFRA, OCT & SCT, frequency deviation
Procedia PDF Downloads 9541168 Economic and Technical Study for Hybrid (PV/Wind) Power System in the North East of Algeria
Authors: Nabila Louai, Fouad Khaldi, Houria Benharchache
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In this paper, the case of meeting a household’s electrical energy demand with hybrid systems has been examined. The objective is to study technological feasibility and economic viability of the electrification project by a hybrid system (PV/ wind) of a residential home located in Batna-Algeria and to reduce the emissions from traditional power by using renewable energy. An autonomous hybrid wind/photovoltaic (PV)/battery power system and a PV/Wind grid connected system, has been carried out using Hybrid Optimization Model for Electric Renewable (HOMER) simulation software. As a result, it has been found that electricity from the grid can be supplied at a lower price than electricity from renewable energy at this moment.Keywords: batna, household, hybrid system, renewable energy, techno-economy
Procedia PDF Downloads 5981167 HRV Analysis Based Arrhythmic Beat Detection Using kNN Classifier
Authors: Onder Yakut, Oguzhan Timus, Emine Dogru Bolat
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Health diseases have a vital significance affecting human being's life and life quality. Sudden death events can be prevented owing to early diagnosis and treatment methods. Electrical signals, taken from the human being's body using non-invasive methods and showing the heart activity is called Electrocardiogram (ECG). The ECG signal is used for following daily activity of the heart by clinicians. Heart Rate Variability (HRV) is a physiological parameter giving the variation between the heart beats. ECG data taken from MITBIH Arrhythmia Database is used in the model employed in this study. The detection of arrhythmic heart beats is aimed utilizing the features extracted from the HRV time domain parameters. The developed model provides a satisfactory performance with ~89% accuracy, 91.7 % sensitivity and 85% specificity rates for the detection of arrhythmic beats.Keywords: arrhythmic beat detection, ECG, HRV, kNN classifier
Procedia PDF Downloads 3501166 Plasma Systems Application in Treating Automobile Exhaust Gases for a Clean Environment (Case Study)
Authors: Tahsen Abdalwahab Ibraheem Albehege
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Exhaust fuel purification is of great importance to prevent the emission of major pollutants into the atmosphere such as diesel particulates and nitrogen oxides and meet environmental regulations, so environmental impacts are a primary concern of Diesel Exhaust Gas (DEG) which contains hazardous substances harmful to the environment as well as human health.We can not plasma formed through directing electrical energy to create free electrons, which in turn can react with gaseous species, but we can by used to treat engine exhaust gases. . By NO that has been reportedly oxidized to HNO3 and then into ammonium nitrate, and then condensed and removed. In general, thermal plasmas are formed by heating a system to high temperatures 2,000 degrees C, however this can be inefficient and can require extensive thermal management.Keywords: plasma system application, project physics, oxidizing environment, electromagnetically
Procedia PDF Downloads 971165 Advanced Simulation of Power Consumption of Electric Vehicles
Authors: Ilya Kavalchuk, Hayrettin Arisoy, Alex Stojcevski, Aman Maun Than Oo
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Electric vehicles are one of the most complicated electric devices to simulate due to the significant number of different processes involved in electrical structure of it. There are concurrent processes of energy consumption and generation with different onboard systems, which make simulation tasks more complicated to perform. More accurate simulation on energy consumption can provide a better understanding of all energy management for electric transport. As a result of all those processes, electric transport can allow for a more sustainable future and become more convenient in relation to the distance range and recharging time. This paper discusses the problems of energy consumption simulations for electric vehicles using different software packages to provide ideas on how to make this process more precise, which can help engineers create better energy management strategies for electric vehicles.Keywords: electric vehicles, EV, power consumption, power management, simulation
Procedia PDF Downloads 5131164 An Automated Sensor System for Cochlear Implants Electrode Array Insertion
Authors: Lei Hou, Xinli Du, Nikolaos Boulgouris
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A cochlear implant, referred to as a CI, is a small electronic device that can provide direct electrical stimulation to the auditory nerve. During cochlear implant surgery, atraumatic electrode array insertion is considered to be a crucial step. However, during implantation, the mechanical behaviour of an electrode array inside the cochlea is not known. The behaviour of an electrode array inside of the cochlea is hardly identified by regular methods. In this study, a CI electrode array capacitive sensor system is proposed. It is able to automatically determine the array state as a result of the capacitance variations. Instead of applying sensors to the electrode array, the capacitance information from the electrodes will be gathered and analysed. Results reveal that this sensing method is capable of recognising different states when fed into a pre-shaped model.Keywords: cochlear implant, electrode, hearing preservation, insertion force, capacitive sensing
Procedia PDF Downloads 2351163 Additive White Gaussian Noise Filtering from ECG by Wiener Filter and Median Filter: A Comparative Study
Authors: Hossein Javidnia, Salehe Taheri
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The Electrocardiogram (ECG) is the recording of the heart’s electrical potential versus time. ECG signals are often contaminated with noise such as baseline wander and muscle noise. As these signals have been widely used in clinical studies to detect heart diseases, it is essential to filter these noises. In this paper we compare performance of Wiener Filtering and Median Filtering methods to filter Additive White Gaussian (AWG) noise with the determined signal to noise ratio (SNR) ranging from 3 to 5 dB applied to long-term ECG recordings samples. Root mean square error (RMSE) and coefficient of determination (R2) between the filtered ECG and original ECG was used as the filter performance indicator. Experimental results show that Wiener filter has better noise filtering performance than Median filter.Keywords: ECG noise filtering, Wiener filtering, median filtering, Gaussian noise, filtering performance
Procedia PDF Downloads 5271162 Umm Arrazam, Libyan Driling Fluid Resistivity Evaluation
Authors: Omar Hussein El Ayadi, Ali Mustafa Alkekly, Nader Ahmad Musa
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Search and evaluate locale source of raw material which can be used as drilling fluid is one of most important economical target. Hopefully, to use Libyan clay that cost less than importing it from outside. Resistivity measurement and control is of primary concern in connection with electrical logging. The influences of resistivity utilizing Umm Arrazam clay were laboratory investigated at ambient condition (room temperature, atmospheric pressure) to fulfill the aim of the study. Several tests were carried-out on three sets of mud mixture with different densities (8.7, 9.0, and 9.3 ppg) as base mud. The resistivity of mud, mud filtrate, and mud cake were measured using resistivity- meter. Mud water losses were also measured. Several results obtained to describe the relationship between the resistivity ratios of mud filtrate to the mud, and the mud cake to mud. The summary of conclusion is that there are no great differences were obtained during comparison of resistivity and water loss of Umm Arrazam and Wyoming Clay.Keywords: petroleum, drilling, mug, geological engineering
Procedia PDF Downloads 4721161 Lithium-Ion Battery State of Charge Estimation Using One State Hysteresis Model with Nonlinear Estimation Strategies
Authors: Mohammed Farag, Mina Attari, S. Andrew Gadsden, Saeid R. Habibi
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Battery state of charge (SOC) estimation is an important parameter as it measures the total amount of electrical energy stored at a current time. The SOC percentage acts as a fuel gauge if it is compared with a conventional vehicle. Estimating the SOC is, therefore, essential for monitoring the amount of useful life remaining in the battery system. This paper looks at the implementation of three nonlinear estimation strategies for Li-Ion battery SOC estimation. One of the most common behavioral battery models is the one state hysteresis (OSH) model. The extended Kalman filter (EKF), the smooth variable structure filter (SVSF), and the time-varying smoothing boundary layer SVSF are applied on this model, and the results are compared.Keywords: state of charge estimation, battery modeling, one-state hysteresis, filtering and estimation
Procedia PDF Downloads 4411160 Influence of Torrefied Biomass on Co-Combustion Behaviors of Biomass/Lignite Blends
Authors: Aysen Caliskan, Hanzade Haykiri-Acma, Serdar Yaman
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Co-firing of coal and biomass blends is an effective method to reduce carbon dioxide emissions released by burning coals, thanks to the carbon-neutral nature of biomass. Besides, usage of biomass that is renewable and sustainable energy resource mitigates the dependency on fossil fuels for power generation. However, most of the biomass species has negative aspects such as low calorific value, high moisture and volatile matter contents compared to coal. Torrefaction is a promising technique in order to upgrade the fuel properties of biomass through thermal treatment. That is, this technique improves the calorific value of biomass along with serious reductions in the moisture and volatile matter contents. In this context, several woody biomass materials including Rhododendron, hybrid poplar, and ash-tree were subjected to torrefaction process in a horizontal tube furnace at 200°C under nitrogen flow. In this way, the solid residue obtained from torrefaction that is also called as 'biochar' was obtained and analyzed to monitor the variations taking place in biomass properties. On the other hand, some Turkish lignites from Elbistan, Adıyaman-Gölbaşı and Çorum-Dodurga deposits were chosen as coal samples since these lignites are of great importance in lignite-fired power stations in Turkey. These lignites were blended with the obtained biochars for which the blending ratio of biochars was kept at 10 wt% and the lignites were the dominant constituents in the fuel blends. Burning tests of the lignites, biomasses, biochars, and blends were performed using a thermogravimetric analyzer up to 900°C with a heating rate of 40°C/min under dry air atmosphere. Based on these burning tests, properties relevant to burning characteristics such as the burning reactivity and burnout yields etc. could be compared to justify the effects of torrefaction and blending. Besides, some characterization techniques including X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) were also conducted for the untreated biomass and torrefied biomass (biochar) samples, lignites and their blends to examine the co-combustion characteristics elaborately. Results of this study revealed the fact that blending of lignite with 10 wt% biochar created synergistic behaviors during co-combustion in comparison to the individual burning of the ingredient fuels in the blends. Burnout and ignition performances of each blend were compared by taking into account the lignite and biomass structures and characteristics. The blend that has the best co-combustion profile and ignition properties was selected. Even though final burnouts of the lignites were decreased due to the addition of biomass, co-combustion process acts as a reasonable and sustainable solution due to its environmentally friendly benefits such as reductions in net carbon dioxide (CO2), SOx and hazardous organic chemicals derived from volatiles.Keywords: burnout performance, co-combustion, thermal analysis, torrefaction pretreatment
Procedia PDF Downloads 3381159 Microstructural and Transport Properties of La0.7Sr0.3CoO3 Thin Films Obtained by Metal-Organic Deposition
Authors: K. Daoudi, Z. Othmen, S. El Helali, M.Oueslati, M. Oumezzine
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La0.7Sr0.3CoO3 thin films have been epitaxially grown on LaAlO3 and SrTiO3 (001) single-crystal substrates by metal organic deposition process. The structural and micro structural properties of the obtained films have been investigated by means of high resolution X-ray diffraction, Raman spectroscopy and transmission microscopy observations on cross-sections techniques. We noted a close dependence of the crystallinity on the used substrate and the film thickness. By increasing the annealing temperature to 1000ºC and the film thickness to 100 nm, the electrical resistivity was decreased by several orders of magnitude. The film resistivity reaches approximately 3~4 x10-4 Ω.cm in a wide interval of temperature 77-320 K, making this material a promising candidate for a variety of applications.Keywords: cobaltite, thin films, epitaxial growth, MOD, TEM
Procedia PDF Downloads 3301158 Strongly Disordered Conductors and Insulators in Holography
Authors: Matthew Stephenson
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We study the electrical conductivity of strongly disordered, strongly coupled quantum field theories, holographically dual to non-perturbatively disordered uncharged black holes. The computation reduces to solving a diffusive hydrostatic equation for an emergent horizon fluid. We demonstrate that a large class of theories in two spatial dimensions have a universal conductivity independent of disorder strength, and rigorously rule out disorder-driven conductor-insulator transitions in many theories. We present a (fine-tuned) axion-dilaton bulk theory which realizes the conductor-insulator transition, interpreted as a classical percolation transition in the horizon fluid. We address aspects of strongly disordered holography that can and cannot be addressed via mean-field modeling, such as massive gravity.Keywords: theoretical physics, black holes, holography, high energy
Procedia PDF Downloads 1761157 Metal Contents in Bird Feathers (Columba livia) from Mt Etna Volcano: Volcanic Plume Contribution and Biological Fractionation
Authors: Edda E. Falcone, Cinzia Federico, Sergio Bellomo, Lorenzo Brusca, Manfredi Longo, Walter D’Alessandro
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Although trace metals are an essential element for living beings, they can become toxic at high concentrations. Their potential toxicity is related not only to the total content in the environment but mostly upon their bioavailability. Volcanoes are important natural metal emitters and they can deeply affect the quality of air, water and soils, as well as the human health. Trace metals tend to accumulate in the tissues of living organisms, depending on the metal contents in food, air and water and on the exposure time. Birds are considered as bioindicators of interest, because their feathers directly reflects the metals uptake from the blood. Birds are exposed to the atmospheric pollution through the contact with rainfall, dust, and aerosol, and they accumulate metals over the whole life cycle. We report on the first data combining the rainfall metal content in three different areas of Mt Etna, variably fumigated by the volcanic plume, and the metal contents in the feathers of pigeons, collected in the same areas. Rainfall samples were collected from three rain gauges placed at different elevation on the Eastern flank of the volcano, the most exposed to airborne plume, filtered, treated with HNO₃ Suprapur-grade and analyzed for Fe, Cr, Co, Ni, Se, Zn, Cu, Sr, Ba, Cd and As by ICP-MS technique, and major ions by ion chromatography. Feathers were collected from single individuals, in the same areas where the rain gauges were installed. Additionally, some samples were collected in an urban area, poorly interested by the volcanic plume. The samples were rinsed in MilliQ water and acetone, dried at 50°C until constant weight and digested in a mixture of 2:1 HNO₃ (65%) - H₂O₂ (30%) Suprapur-grade for 25-50 mg of sample, in a bath at near-to-boiling temperature. The solutions were diluted up to 20 ml prior to be analyzed by ICP-MS. The rainfall samples most contaminated by the plume were collected at close distance from the summit craters (less than 6 km), and show lower pH values and higher concentrations for all analyzed metals relative to those from the sites at lower elevation. Analyzed samples are enriched in both metals directly emitted by the volcanic plume and transported by acidic gases (SO₂, HCl, HF), and metals leached from the airborne volcanic ash. Feathers show different patterns in the different sites related to the exposure to natural or anthropogenic pollutants. They show abundance ratios similar to rainfall for lithophile elements (Ba, Sr), whereas are enriched in Zn and Se, known for their antioxidant properties, probably as adaptive response to oxidative stress induced by toxic metal exposure. The pigeons revealed a clear heterogeneity of metal uptake in the different parts of the volcano, as an effect of volcanic plume impact. Additionally, some physiological processes can modify the fate of some metals after uptake and this offer some insights for translational studies.Keywords: bioindicators, environmental pollution, feathers, trace metals, volcanic plume
Procedia PDF Downloads 1421156 Optimization of Hydrogel Conductive Nanocomposite as Solar Cell
Authors: Shimaa M. Elsaeed, Reem K. Farag, Ibrahim M. Nassar
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Hydrogel conductive polymer nanocomposite fabricated via in-situ polymerization of polyaniline (PANI) inside thermosensitive hydrogels based on hydroxy ethyl meth acrylate (HEMA) copolymer with 2-acrylamido-2-methyl propane sulfonic acid (AMPS). SEM micrographs show the nanometric size of the conductive material (polyaniline, PANI) dispersed in the hydrogel matrix. The swelling parameters of hydrogel are measured. The incorporation of PANI improves the mechanical properties and swelling up to 30,000% without breaking. X-ray diffraction shows that typical polyaniline crystallization is formed in composite, which is advantageous to increase the electrical conductivity of the composite hydrogel. Open-circuit voltage (I-V) curve fill factor of the highest photo-conversion efficiency and enhanced to use in solar cell.Keywords: hydrogel, solar cell, conductive polymer, nanocomposite
Procedia PDF Downloads 3981155 Design and Simulation on Technology Capabilities in Developing countries, Design and Engineering Approach
Authors: S. Abedi, M. R. Soroush, M. Mousakhani
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According to studies in the field of technology capabilities we identify the most important indicators to evaluate the level of "Design and Engineering" capabilities. Since the technology development correlates with the level of technology capabilities trying to promote its key importance. In this research by using FDM, the right combination of D&E capabilities indicators according to the auto industry is presented. Finally, with modeling evaluation of D&E capabilities by using FIS and check its reliability, five levels were determined to evaluate the D&E capabilities. We have analyzed 80 companies in auto industry and determined D&E capabilities of each level. Field of company activity indicators has been divided into four categories, Suspension group, Electrical group, Engine groups and trims group. The results show that half of the surveyed companies had D&E capabilities in Level 1 and 2 or in other words very low and low level of D&E.Keywords: developing countries, D&E capabilities, technology capabilities, auto industry
Procedia PDF Downloads 5341154 Structural, Optical and Electrical Properties of PbS Thin Films Deposited by CBD at Different Bath pH
Authors: Lynda Beddek, Nadhir Attaf, Mohamed Salah Aida
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PbS thin films were grown on glass substrates by chemical bath deposition (CBD). The precursor aqueous bath contained 1 mole of lead nitrate, 1 mole of Thiourea and complexing agents (triethanolamine (TEA) and NaOH). Bath temperature and deposition time were fixed at 60°C and 3 hours, respectively. However, the PH of bath was varied from 10.5 to 12.5. Structural properties of the deposited films were characterized by X-ray diffraction and Raman spectroscopy. The preferred direction was revealed to be along (111) and the PbS crystal structure was confirmed. Strains and grains sizes were also calculated. Optical studies showed that films thicknesses do not exceed 600nm. Energy band gap values of films decreases with increase in pH and reached a value ~ 0.4eV at pH equal 12.5. The small value of the energy band gap makes PbS one of the most interesting candidate for solar energy conversion near the infrared ray.Keywords: CBD, PbS, pH, thin films, x-ray diffraction
Procedia PDF Downloads 4401153 Modeling of Bioelectric Activity of Nerve Cells Using Bond Graph Method
Authors: M. Ghasemi, F. Eskandari, B. Hamzehei, A. R. Arshi
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Bioelectric activity of nervous cells might be changed causing by various factors. This alteration can lead to unforeseen circumstances in other organs of the body. Therefore, the purpose of this study was to model a single neuron and its behavior under an initial stimulation. This study was developed based on cable theory by means of the Bond Graph method. The numerical values of the parameters were derived from empirical studies of cellular electrophysiology experiments. Initial excitation was applied through square current functions, and the resulted action potential was estimated along the neuron. The results revealed that the model was developed in this research adapted with the results of experimental studies and demonstrated the electrical behavior of nervous cells properly.Keywords: bond graph, stimulation, nervous cells, modeling
Procedia PDF Downloads 4251152 The Uniting Control Lyapunov Functions in Permanent Magnet Synchronous Linear Motor
Authors: Yi-Fei Yang, Nai-Bao He, Shao-Bang Xing
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This study investigates the permanent magnet synchronous linear motor (PMSLM) chaotic motion under the specific physical parameters, the stability and the security of motor-driven system will be unavoidably influenced. Therefore, it is really necessary to investigate the methods of controlling or suppressing chaos in PMSLM. Firstly, we derive a chaotic model of PMSLM in the closed-loop system. Secondly, in order to realize the local asymptotic stabilization of the mechanical subsystem and the global stabilization of the motor-driven system including electrical subsystem, we propose an improved uniting control lyapunov functions by introducing backstepping approach. Finally, an illustrated example is also given to show the electiveness of the obtained results.Keywords: linear motor, lyapunov functions, chao control, hybrid controller
Procedia PDF Downloads 3351151 Backstepping Controller for a Variable Wind Speed Energy Conversion System Based on a DFIG
Authors: Sara Mensou, Ahmed Essadki, Issam Minka, Tamou Nasser, Badr Bououlid Idrissi
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In this paper we present a contribution for the modeling and control of wind energy conversion system based on a Doubly Fed Induction Generator (DFIG). Since the wind speed is random the system has to produce an optimal electrical power to the Network and ensures important strength and stability. In this work, the Backstepping controller is used to control the generator via two converter witch placed a DC bus capacitor and connected to the grid by a Filter R-L, in order to optimize capture wind energy. All is simulated and presented under MATLAB/Simulink Software to show performance and robustness of the proposed controller.Keywords: wind turbine, doubly fed induction generator, MPPT control, backstepping controller, power converter
Procedia PDF Downloads 1881150 Optimization Method of Dispersed Generation in Electrical Distribution Systems
Authors: Mahmoud Samkan
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Dispersed Generation (DG) is a promising solution to many power system problems such as voltage regulation and power loss. This paper proposes a heuristic two-step method to optimize the location and size of DG for reducing active power losses and, therefore, improve the voltage profile in radial distribution networks. In addition to a DG placed at the system load gravity center, this method consists in assigning a DG to each lateral of the network. After having determined the central DG placement, the location and size of each lateral DG are predetermined in the first step. The results are then refined in the second step. This method is tested for 33-bus system for 100% DG penetration. The results obtained are compared with those of other methods found in the literature.Keywords: optimal location, optimal size, dispersed generation (DG), radial distribution networks, reducing losses
Procedia PDF Downloads 4421149 Treatment of Oil Recovery Water Using Direct and Indirect Electrochemical Oxidation
Authors: Tareg Omar Mansour, Khaled Omar Elhaji
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Model solutions of pentanol in the salt water of various concentrations were subjected to electrochemical oxidation using a dimensionally stable anode (DSA) and a platinised titanium cathode. The removal of pentanol was analysed over time using gas chromatography (GC) and by monitoring the total organic carbon (TOC) concentration of the reaction mixture. It was found that the removal of pentanol occurred more efficiently at higher salinities and higher applied electrical current values. When using a salt concentration of 20,000 ppm and an applied current of 100 mA there was a decrease in concentration of pentanol of 15 %. When the salt concentration and applied current were increased to 58,000 ppm and 500 mA respectively, the decrease in concentration was improved to 64 %.Keywords: dimensionally stable anode (DSA), total organic hydrocarbon (TOC), gas chromatography mass spectrometry (GCMS), electrochemical oxidation
Procedia PDF Downloads 3801148 Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing
Authors: M. S. Al-Assiri, M. M. El-Desoky, A. A. Bahgat
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Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process.Keywords: sol-gel, thermoelectric power, XRD, TEM, gas sensing
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