Search results for: peak frequency

Authors: Ghulam Mustafa Peerzada, Shagufta Rashid, Nadeem Bashir

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These the influence of initial reagent concentrations on the Belousov-Zhabotinsky (BZ) system with Mn2+/Mn3+ as redox catalyst, inorganic bromate as oxidant and pyrogallol as organic substrate was studied. The reactions were monitored by potentiometery in oxidation reduction potential (ORP) mode. The aforesaid reagents were mixed with varying concentrations to evolve the optimal concentrations at which the reaction system exhibited better oscillations. The various oscillatory parameters such as induction period (tin), time period (tp), frequency (v), amplitude (A) and number of oscillations (n) were derived and the dependence of concentration of the reacting species on these oscillatory parameters was interpreted on the basis of the Field-Koros-Noyes mechanism. Ferroin based BZ system with pyrogallol as organic substrate was optimized under CSTR condition at temperature of 30±0.1oC Effect of molecules like monomer and polymer as additives to the system was checked and their interaction with the system was also studied. It has been observed that the monomer affects the time period, while the polymer has its effect on the amplitude of oscillations because of monomer’s interaction with the bromine and polymer’s with that of the Ferroin.

Keywords: Belousov Zhabotinsky reaction, oscillatory parameters, polymer, pyrogallol

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Authors: Alok Tiwari, Ming Show Wong

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Lanthanum (La) doped Barium Tin Oxide (BaSnO₃) film is an excellent alternative for expensive Transparent Conducting Oxides (TCOs) film such as Indium Tin Oxide (ITO). However single crystal film of La-doped BaSnO₃ has been reported with a good amount of conductivity and transparency but in order to improve its reachability, it is important to grow doped BaSO₃ films on an inexpensive substrate. La-doped BaSnO₃ thin films have been grown on quartz substrate by Radio Frequency (RF) sputtering at a different substrate temperature (from 200⁰C to 750⁰C). The thickness of the film measured was varying from 360nm to 380nm with varying substrate temperature. Structure, optical and electrical properties have been studied. The carrier concentration is seen to be decreasing as we enhance the substrate temperature while mobility found to be increased up to 9.3 cm²/V-S. At low substrate temperature resistivity found was lower (< 3x10⁻³ ohm-cm) while sudden enhancement was seen as substrate temperature raises and the trend continues further with increasing substrate temperature. Optical transmittance is getting better with higher substrate temperature from 70% at 200⁰C to > 80% at 750⁰C. Overall, understanding of changes in microstructure, electrical and optical properties of a thin film by varying substrate temperature has been reported successfully.

Keywords: conductivity, perovskite, mobility, TCO film

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Authors: Chia-Ju Peng, Shih-Jui Chen

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This paper proposes a method to discriminate electroencephalogram (EEG) signals between different concentration states using empirical mode decomposition (EMD). Brain-computer interface (BCI), also called brain-machine interface, is a direct communication pathway between the brain and an external device without the inherent pathway such as the peripheral nervous system or skeletal muscles. Attention level is a common index as a control signal of BCI systems. The EEG signals acquired from people paying attention or in relaxation, respectively, are decomposed into a set of intrinsic mode functions (IMF) by EMD. Fast Fourier transform (FFT) analysis is then applied to each IMF to obtain the frequency spectrums. By observing power spectrums of IMFs, the proposed method has the better identification of EEG attention level than the original EEG signals between different concentration states. The band power of IMF3 is the most obvious especially in β wave, which corresponds to fully awake and generally alert. The signal processing method and results of this experiment paves a new way for BCI robotic system using the attention-level control strategy. The integrated signal processing method reveals appropriate information for discrimination of the attention and relaxation, contributing to a more enhanced BCI performance.

Keywords: biomedical engineering, brain computer interface, electroencephalography, rehabilitation

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Authors: Mozhgan Aliakbari, Sara Moridpour

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In recent years, much attention has been given to truck drivers’ fatigue management. Long working hours negatively influence truck drivers’ physiology, health, and safety. However, there is little empirical research in the heavy vehicle transport sector in Australia to identify the influence of working hours’ management on drivers’ fatigue and consequently, on the risk of crashes and injuries. There is no national legislation regulating the number of hours or kilometres travelled by truck drivers. Consequently, it is almost impossible to define a standard number of hours or kilometres for truck drivers in a safety management system. This paper reviews the existing studies concerning safe system interventions such as tachographs in relation to fatigue caused by long working hours. This paper also reviews the literature to identify the influence of frequency of rest breaks on the reduction of work-related road transport accidents involving trucks. A framework is presented to manage truck drivers’ fatigue, which may result in the reduction of injuries and fatalities involving heavy vehicles.

Keywords: fatigue, time management, trucks, traffic safety

Procedia PDF Downloads 291

Authors: S. Kampeephat, P. Krachodnok, R. Wongsan

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The conventional rectangular horn has been used for microwave antenna a long time. Its gain can be increased by enlarging the construction of horn to flare exponentially. This paper presents a study of the shaped woodpile Electromagnetic Band Gap (EBG) to improve its gain for conventional horn without construction enlargement. The gain enhancement synthesis method for shaped woodpile EBG that has to transfer the electromagnetic fields from aperture of a horn antenna through woodpile EBG is presented by using the variety of shaped woodpile EBGs such as planar, triangular, quadratic, circular, gaussian, cosine, and squared cosine structures. The proposed technique has the advantages of low profile, low cost for fabrication and light weight. The antenna characteristics such as reflection coefficient (S11), radiation patterns and gain are simulated by utilized A Computer Simulation Technology (CST) software. With the proposed concept, an antenna prototype was fabricated and experimented. The S11 and radiation patterns obtained from measurements show a good impedance matching and a gain enhancement of the proposed antenna. The gain at dominant frequency of 10 GHz is 25.6 dB, application for X- and Ku-Band Radar, that higher than the gain of the basic rectangular horn antenna around 8 dB with adding only one appropriated EBG structures.

Keywords: conventional rectangular horn antenna, electromagnetic band gap, gain enhancement, X- and Ku-band radar

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Authors: Andrew Anis Fakhrey Mosaad

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Introduction: Sports- and physical activity-related injuries may be more likely if there is a genetic predisposition, improper coaching and/or training, and no follow-up care from sports medicine. Goal: To evaluate the frequency of injuries among athletes receiving care at a sportsfocused physical therapy clinic. Methods: The survey of injuries in athletes' treatment records over a period of eight years of activity was done to obtain data. The data collected included: the patient's features, the sport, the type of injury, the injury's characteristics, and the body portion injured. Results: The athletes were drawn from 1090 patient/athlete records, had an average age of 25, participated in 44 different sports, and were 75% men on average. Joint injuries were the most frequent type of injury, then damage to the muscles and bones. The most prevalent type of injury was chronic (47%), while the knee, ankle, and shoulder were the most frequently damaged body parts. The most injured athletes were seen in soccer, futsal, and track and field, respectively, out of all the sports. Conclusion: The most popular sport among injured players was soccer, and the most common injury type was joint damage, with the knee being the most often damaged body area. The majority of the injuries were chronic.

Keywords: sports injuries, athletes, joint injuries, injured players

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Authors: Ramadhani Yasyfi Cysela, Adinda Syifa Azhari, Eleonora Agustine

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The World Health Organization (WHO) estimates that about a quarter of the diseases facing mankind today occur due to environmental pollution. The soil is a part of environment that have a widespread problem. The contaminated soil should no longer be used to grow food because the chemicals can leech into the food and harm people who eat it. The chemical fertilizer industry gives specific effect due to soil pollution. To determine ammonia and urea emissions from fertilizer industry, we can use physical characteristic of soil, which is magnetic susceptibility. Rock magnetism is used as a proxy indicator to determine changes in physical properties. Magnetic susceptibilities of samples in low and high frequency have been measured by Bartington MS2B magnetic susceptibility measurement device. The sample was taken from different area which located closer by pollution source and far from the pollution source. The susceptibility values of polluted samples in topsoil were quite low, with range from 187.1- 494.8 [x 10-8 m3 kg-1] when free polluted area’s sample has high values (1188.7- 2237.8 [x 10-8 m3 kg-1 ]). From this studies shows that susceptibility values in areas of the fertilizer industry are lower than the free polluted area.

Keywords: environmental, magnetic susceptibility, rock magnetism, soil pollution

Procedia PDF Downloads 358

Authors: Sunil Kumar Ghosh

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Som plant (Machilus bombycina King) is an important plant in agroforestry system. It is cultivated in north -east part of India. It is cultivated in agricultural land by the marginal farmers for multi-storeyed cultivation with intercropping. Localized cottage industries are involved with this plant like sericulture industry (muga silk worm cultivation). Clothes are produced from this sericulture industry. Leaves of som plants are major food of muga silk worm ( Antherea assama ). Nutritional value of leaves plays an important role in the larval growth and silk productivity. The plant also has timber value. The plant is susceptible to mite pest (Tetranychus sp.) causes heavy damage to tender leaves. Lower population was recorded during 7th to 38th standard week, during 3rd week of February to 4th week of September and higher population was during 46th to 51st standard week, during 3rd week of November to 3rd week of December and peak population (6.06/3 leaves) was recorded on 46th standard week that is on 3rd week of November. Correlation studies revealed that mite population had a significant negative correlation with temperature and non-significant positive correlation with relative humidity. This indicates that activity of mites population increase with the rise of relative humidity and decrease with the rise of temperature. Tobacco leaf extracts was found most effective against mite providing 40.51% suppression, closely followed by extracts of Spilanthes (39.06% suppression). Extracts of Garlic and extracts of Polygonum plant gave moderate results, recording about 38.10% and 37.78% mite suppression respectively. The polygonum (Polygonum hydropiper) plant (floral parts), pongamia (Pongamia pinnata) leaves, garlic (Allium sativum), spilanthes (Spilanthes paniculata) (floral parts) were extracted in methanol. Synthetic insecticides contaminate plant leaves with the toxic chemicals. Plant extracts are of biological origin having low or no hazardous effect on health and environment and so can be incorporated in organic cultivation.

Keywords: Abiotic factors, incidence, botanical extracts, organic cultivation, silk industry

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Authors: Hyo-In Koh, Anders Nordborg, Alex Sievi, Chun-Kwon Park

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The noise source for the interior room of the high speed train is constituted by the rolling contact between the wheel and the rail, aerodynamic noise and structure-borne sound generated through the vibrations of bogie, connection points to the carbody. Air-borne sound is radiated through the panels and structures into the interior room of the trains. The high-speed lines are constructed with slab track systems and many tunnels. The interior noise level and the frequency characteristics vary according to types of the track structure and the infrastructure. In this paper the main sound sources and the transfer paths are studied to find out the contribution characteristics of the sources to the interior noise of a high-speed rail vehicle. For the identification of the acoustic power of each parts of the rolling noise sources a calculation model of wheel/rail noise is developed and used. For the analysis of the transmission of the sources to the interior noise noise and vibration are measured during the operation of the vehicle. According to operation speeds, the mainly contributed sources and the paths could be analyzed. Results of the calculations on the source generation and the results of the measurement with a high-speed train are shown and discussed.

Keywords: rail vehicle, high-speed, interior noise, noise source

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Authors: David W. Hill, Linda W. Glass, Jakob L. Vingren

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Maximal accumulated oxygen deficit (MAOD), the gold standard measure of anaerobic capacity, is the difference between the oxygen cost of exhaustive severe intensity exercise and the accumulated oxygen consumption (O2; mL·kg–1). In theory, MAOD can be estimated as the sum of independent estimates of the phosphocreatine and glycolysis contributions, which we refer to as PCr+glycolysis. Purpose: The purpose was to test the hypothesis that PCr+glycolysis provides a valid measure of anaerobic capacity in cycling and running. Methods: The participants were 27 women (mean ± SD, age 22 ±1 y, height 165 ± 7 cm, weight 63.4 ± 9.7 kg) and 25 men (age 22 ± 1 y, height 179 ± 6 cm, weight 80.8 ± 14.8 kg). They performed two exhaustive cycling and running tests, at speeds and work rates that were tolerable for ~5 min. The rate of oxygen consumption (VO2; mL·kg–1·min–1) was measured in warmups, in the tests, and during 7 min of recovery. Fingerprick blood samples obtained after exercise were analysed to determine peak blood lactate concentration (PeakLac). The VO2 response in exercise was fitted to a model, with a fast ‘primary’ phase followed by a delayed ‘slow’ component, from which was calculated the accumulated O2 and the excess O2 attributable to the slow component. The VO2 response in recovery was fitted to a model with a fast phase and slow component, sharing a common time delay. Oxygen demand (in mL·kg–1·min–1) was determined by extrapolation from steady-state VO2 in warmups; the total oxygen cost (in mL·kg–1) was determined by multiplying this demand by time to exhaustion and adding the excess O2; then, MAOD was calculated as total oxygen cost minus accumulated O2. The phosphocreatine contribution (area under the fast phase of the post-exercise VO2) and the glycolytic contribution (converted from PeakLac) were summed to give PCr+glycolysis. There was not an interaction effect involving sex, so values for anaerobic capacity were examined using a two-way ANOVA, with repeated measures across method (PCr+glycolysis vs MAOD) and mode (cycling vs running). Results: There was a significant effect only for exercise mode. There was no difference between MAOD and PCr+glycolysis: values were 59 ± 6 mL·kg–1 and 61 ± 8 mL·kg–1 in cycling and 78 ± 7 mL·kg–1 and 75 ± 8 mL·kg–1 in running. Discussion: PCr+glycolysis is a valid measure of anaerobic capacity in cycling and running, and it is as valid for women as for men.

Keywords: alactic, anaerobic, cycling, ergometer, glycolysis, lactic, lactate, oxygen deficit, phosphocreatine, running, treadmill

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Authors: Artem A. Krylov

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Instrumental seismological researches in water areas are complicated and expensive, that leads to the lack of strong motion records in most offshore regions. In the same time the number of offshore industrial infrastructure objects, such as oil rigs, subsea pipelines, is constantly increasing. The empirical Green’s function technique proved to be very effective for accelerograms synthesis under the conditions of poorly described seismic wave propagation medium. But the selection of suitable small earthquake record in offshore regions as an empirical Green’s function is a problem because of short seafloor instrumental seismological investigation results usually with weak micro-earthquakes recordings. An approach based on moving average smoothing in the frequency domain is presented for preliminary processing of weak micro-earthquake records before using it as empirical Green’s function. The method results in significant waveform correction for modeled event. The case study for 2009 L’Aquila earthquake was used to demonstrate the suitability of the method. This work was supported by the Russian Foundation of Basic Research (project № 18-35-00474 mol_a).

Keywords: accelerogram synthesis, empirical Green's function, marine seismology, microearthquakes

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Authors: Voss Harrigan, Korey Carter, Mohammad Reza Shaeri

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Detrimental effects of lunar dust on space hardware, spacesuits, and astronauts’ health have been already identified during Apollo missions. Developing effective dust mitigation technologies is critically important for successful space exploration and related missions in NASA applications. In this study, an electrostatic cleaning system (ECS) integrated with a negatively ionized Thunderon brush was developed to mitigate small-sized lunar dust particles with diameters ranging from 0.04 µm to 35 µm, and the mean and median size of 7 µm and 5 µm, respectively. It was found that the frequency pulses of the negative ion generator caused particles to stick to the Thunderon bristles and repel between the pulses. The brush was used manually to ensure that particles were removed from areas where the ECS failed to mitigate the lunar simulant. The acquired data demonstrated that the developed system removed over 91-96% of the lunar dust particles. The present study was performed as a proof-of-concept to enhance the cleaning performance of ECSs by integrating a brushing process. Suggestions were made to further improve the performance of the developed technology through future research.

Keywords: lunar dust mitigation, electrostatic cleaning system, Brushing, Thunderon brush, cleaning rate

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Authors: Jennifer de Jesus, Ares Baron Talusan, Steven Valerio

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This paper aims to conduct an evaluation of the drainage system in a specific village in Apalit, Pampanga using the geographic information system to easily identify inadequate drainage lines that needs rehabilitation to aid in flooding problem in the area. The researchers will be utilizing two methods and software to be able to strategically assess each drainage line in the village– the two methods were the rational method and the Manning's Formula for Open Channel Flow and compared it to each other, and the software to be used was Google Earth Pro by 2020 Google LLC. The results must satisfy the statement QManning > QRational to be able to see if the specific line and section is adequate; otherwise, it is inadequate; dimensions needed to be recomputed until it became adequate. The use of the software is the visualization of data collected from the computations to clearly see in which areas the drainage lines were adequate or not. The researchers were then able to conclude that the drainage system should be considered inadequate, seeing as most of the lines are unable to accommodate certain intensities of rainfall. The researchers have also concluded that line rehabilitation is a must to proceed.

Keywords: strategic evaluation, drainage system, as-built plans, inadequacy, rainfall intensity-duration-frequency data, rational method, manning’s equation for open channel flow

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Authors: Noratiqah Mohd Ariff, Abdul Aziz Jemain, Mohd Aftar Abu Bakar

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The construction of Intensity-Duration-Frequency (IDF) curves is one of the most common and useful tools in order to design hydraulic structures and to provide a mathematical relationship between rainfall characteristics. IDF curves, especially those in Peninsular Malaysia, are often built using moving windows of rainfalls. However, these windows do not represent the actual rainfall events since the duration of rainfalls is usually prefixed. Hence, instead of using moving windows, this study aims to find regionalized distributions for IDF curves of extreme rainfalls based on storm events. Homogeneity test is performed on annual maximum of storm intensities to identify homogeneous regions of storms in Peninsular Malaysia. The L-moment method is then used to regionalized Generalized Extreme Value (GEV) distribution of these annual maximums and subsequently. IDF curves are constructed using the regional distributions. The differences between the IDF curves obtained and IDF curves found using at-site GEV distributions are observed through the computation of the coefficient of variation of root mean square error, mean percentage difference and the coefficient of determination. The small differences implied that the construction of IDF curves could be simplified by finding a general probability distribution of each region. This will also help in constructing IDF curves for sites with no rainfall station.

Keywords: IDF curves, L-moments, regionalization, storm events

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Authors: Ajay Panchal

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This research introduces the Law of Activity Dominancy (LAD), a foundational theory in neuroscience postulating that simultaneous brain-regulated activities cannot share identical brain wave frequencies. The study explores the LAD through comprehensive observational and statistical analyses, illustrating its applicability across all cognitive functions. Utilizing brain wave frequency data across diverse scenarios, the research derives probabilistic models to predict the likelihood of concurrent cognitive activities. The LAD theory's predictive power extends to all neurological conditions, offering insights into Alzheimer's disease, major depressive disorder, epilepsy, schizophrenia, anxiety disorders, OCD, ASD, ADHD etc... By analyzing EEG patterns, the research demonstrates how overlapping brain wave frequencies disrupt specific cognitive and motor functions, aligning with clinical observations. This study also outlines the statistical properties of the LAD, presenting equations to calculate activity probabilities and emphasizing its utility in personalizing cognitive assessments, early disease detection, tailored therapies, optimizing cognitive performance etc... By bridging theoretical neuroscience with practical applications, the research establishes the LAD as a pivotal framework for understanding and enhancing human cognitive functions.

Keywords: Ajay Panchal, cognitive neuroscience, computational neuroscience, theoretical neuroscience

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Authors: P. Ramesh, Aby Joseph, Arya G. Lal, U. S. Aji

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Integration of distributed green renewable energy sources in addition with battery energy storage is an inevitable requirement in a smart grid environment. To achieve this, an Intelligent Green Energy Management System (i-GEMS) needs to be incorporated to ensure coordinated operation between supply and load demand based on the hierarchy of Renewable Energy Sources (RES), battery energy storage and distribution grid. A bi-directional energy harvester is an integral component facilitating Intelligent Green Energy Management System (i-GEMS) and it is required to meet the technical challenges mentioned as follows: (1) capability for bi-directional mode of operation (buck/boost) (2) reduction of circuit parasitic to suppress voltage spikes (3) converter startup problem (4) high frequency magnetics (5) higher power density (6) mode transition issues during battery charging and discharging. This paper is focused to address the above mentioned issues and targeted to design, develop and implement a bi-directional energy harvester with galvanic isolation. In this work, the hardware architecture for bi-directional energy harvester rated 3.5 kW is developed with Isolated Full Bridge Boost Converter (IFBBC) as well as Dual Active Bridge (DAB) Converter configuration using modular power electronics hardware which is identical for both solar PV array and battery energy storage. In IFBBC converter, the current fed full bridge circuit is enabled and voltage fed full bridge circuit is disabled through Pulse Width Modulation (PWM) pulses for boost mode of operation and vice-versa for buck mode of operation. In DAB converter, all the switches are in active state so as to adjust the phase shift angle between primary full bridge and secondary full bridge which in turn decides the power flow directions depending on modes (boost/buck) of operation. Here, the control algorithm is developed to ensure the regulation of the common DC link voltage and maximum power extraction from the renewable energy sources depending on the selected mode (buck/boost) of operation. The circuit analysis and simulation study are conducted using PSIM 9.0 in three scenarios which are - 1.IFBBC with passive clamp, 2. IFBBC with active clamp, 3. DAB converter. In this work, a common hardware prototype for bi-directional energy harvester with 3.5 kW rating is built for IFBBC and DAB converter configurations. The power circuit is equipped with right choice of MOSFETs, gate drivers with galvanic isolation, high frequency transformer, filter capacitors, and filter boost inductor. The experiment was conducted for IFBBC converter with passive clamp under boost mode and the prototype confirmed the simulation results showing the measured efficiency as 88% at 2.5 kW output power. The digital controller hardware platform is developed using floating point microcontroller TMS320F2806x from Texas Instruments. The firmware governing the operation of the bi-directional energy harvester is written in C language and developed using code composer studio. The comprehensive analyses of the power circuit design, control strategy for battery charging/discharging under buck/boost modes and comparative performance evaluation using simulation and experimental results will be presented.

Keywords: bi-directional energy harvester, dual active bridge, isolated full bridge boost converter, intelligent green energy management system, maximum power point tracking, renewable energy sources

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Authors: Pavlo Selyshchev

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A theoretical approach to describe kinetic of heat transfer between an irradiated sample and environment is developed via formalism of the Complex systems and kinetic equations. The irradiated material is a metastable system with non-linear feedbacks, which can give rise to different regimes of buildup and annealing of radiation-induced defects, heating and heat transfer with environment. Irradiation with energetic particles heats the sample and produces defects of the crystal lattice of the sample. The crystal with defects accumulates extra (non-thermal) energy, which is transformed into heat during the defect annealing. Any increase of temperature leads to acceleration of defect annealing, to additional transformation of non-thermal energy into heat and to further growth of the temperature. Thus a non-linear feedback is formed. It is shown that at certain conditions of irradiation this non-linear feedback leads to self-oscillations of the defect density, the temperature of the irradiated sample and the heat transfer between the sample and environment. Simulation and analysis of these phenomena is performed. The frequency of the self-oscillations is obtained. It is determined that the period of the self-oscillations is varied from minutes to several hours depending on conditions of irradiation and properties of the sample. Obtaining results are compared with experimental ones.

Keywords: irradiation, heat transfer, non-linear feed-back, self-oscillations

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Authors: T. D. Tran, H. Schlegel, R. Neugebauer

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Ball screws are an important component in machine tools. In mechatronic systems and machine tools, a ball screw has to work usually at a high speed. Otherwise the axial compliance of the ball screw, in combination with the inertia of the slide, the motor, the coupling and the screw, will cause an oscillation resonance, which limits the systems bandwidth and consequently influences performance of the motion controller. In this paper, the modal analysis method by measuring and analysing the vibrating parameters of the ball screw system to determine the dynamic characteristic of existing structures is used. On the one hand, the results of this study were obtained by the theoretical analysis and the modal testing of a ball screw system test station with the help of an impact hammer, respectively using excitation by motor. The experimental study showed oscillating forms of the ball screw for each frequency and obtained eigenfrequencies of the ball screw system. On the other hand, in this research a simulation with the help of the numerical modal analysis in order to analyse the oscillation and to find the eigenfrequencies of the ball screw system is used. Furthermore, the model order reduction by modal reduction and also according to Guyan is carried out. On the basis of these results a secure and also rapid commissioning of the control loops with regard to operating in their optimal function is targeted.

Keywords: modal analysis, ball screw, controller system, machine tools

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Authors: Anish Bhargava

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By 2050, there will be more plastic than fish in our oceans. 51 trillion micro-plastics pollute our waters and contaminate the food on our plates, increasing the risk of tumours and diseases such as cancer. Our product is a solution to the ever-growing problem of plastic pollution. We call it the SmartBin. The SmartBin is a cylindrical device which will float just below the surface of the water, able to move with the aid of 4 water thrusters situated on the sides. As it floats, our SmartBin will suck water into itself and pump it out through the bottom. All waste is collected into a reusable filter including microplastics measuring down to 1.5mm. A speaker emitting sound at a frequency of 9 hertz ensures marine life stays away from the SmartBin. Featured along with our product is a smartphone app which will enable the user to designate an area for the SmartBin to cover on a satellite image. The SmartBin will then return to its start position near the shore, configured through the app. As global pressure to tackle water pollution continues to increase, environmental spending increases too. As our product provides an effective solution to this issue, we can seize the opportunity and scale our company. Our product is unparalleled. It can move at a high speed, covering a wide area rather than being restricted to one position. We target not only oceans and sea-shores, but also rivers, lakes, reservoirs and canals, as they are much easier to access and control.

Keywords: water, plastic, pollution, solution, hydroclean, smartbin, cleanup

Procedia PDF Downloads 206

Authors: Vikas Kumar

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Portable batteries are reliable source of mobile energy to power smart wearable electronics, medical devices, communications, and others internet of thing (IoT) devices. There is a continuous increase in demand for thinner, more flexible battery with high energy density and reliability to meet the requirement. For a flexible battery, factors that affect these properties are the stability of current collectors, electrode materials and their interfaces with the corrosive electrolytes. State-of-the-art conventional and flexible batteries utilise carbon as an electrode and current collectors which cause high internal resistance (~100 ohms) and limit the peak current to ~1mA. This makes them unsuitable for a wide range of applications. Replacing the carbon parts with metallic components would reduce the internal resistance (and hence reduce parasitic loss), but significantly increases the risk of corrosion due to galvanic interactions within the battery. To overcome these challenges, low cost electroplated nickel (Ni) on copper (Cu) was studied as a potential anode current collector for a zinc-manganese oxide primary battery with different concentration of NH4Cl/ZnCl2 electrolyte. Using electrical impedance spectroscopy (EIS), we monitored the open circuit potential (OCP) of electroplated nickel (different thicknesses) in different concentration of electrolytes to optimise the thickness of Ni coating. Our results show that electroless Ni coating suffer excessive corrosion in these electrolytes. Corrosion rates of Ni coatings for different concentrations of electrolytes have been calculated with Tafel analysis. These results suggest that for electroplated Ni, channelling and/or open porosity is a major issue, which was confirmed by morphological analysis. These channels are an easy pathway for electrolyte to penetrate thorough Ni to corrode the Ni/Cu interface completely. We further investigated the incorporation of a special printed graphene layer on Ni to provide corrosion protection in this corrosive electrolyte medium. We find that the incorporation of printed graphene layer provides the corrosion protection to the Ni and enhances the chemical bonding between the active materials and current collector and also decreases the overall internal resistance of the battery system.

Keywords: corrosion, electrical impedance spectroscopy, flexible battery, graphene, metal current collector

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Authors: V. S. S. Kumar, V. Ramya

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In the modern electronic warfare, the signal scenario is changing at a rapid pace with the introduction of Low Probability of Intercept (LPI) radars. In the modern battlefield, radar system faces serious threats from passive intercept receivers such as Electronic Attack (EA) and Anti-Radiation Missiles (ARMs). To perform necessary target detection and tracking and simultaneously hide themselves from enemy attack, radar systems should be LPI. These LPI radars use a variety of complex signal modulation schemes together with pulse compression with the aid of advancement in signal processing capabilities of the radar such that the radar performs target detection and tracking while simultaneously hiding enemy from attack such as EA etc., thus posing a major challenge to the ES/ELINT receivers. Today an increasing number of LPI radars are being introduced into the modern platforms and weapon systems so these LPI radars created a requirement for the armed forces to develop new techniques, strategies and equipment to counter them. This paper presents various modulation techniques used in generation of LPI signals and development of Time Frequency Algorithms to analyse those signals.

Keywords: anti-radiation missiles, cross terms, electronic attack, electronic intelligence, electronic warfare, intercept receiver, low probability of intercept

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Authors: Weiwei Cui, Dejian Lin, Leigang Zhang, Yao Wang, Zheng Sun, Lianfeng Li

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Built-in test (BIT) is an important technology in testability field, and it is widely used in state monitoring and fault diagnosis. With the improvement of modern equipment performance and complexity, the scope of BIT becomes larger, and it leads to the emergence of false alarm problem. The false alarm makes the health assessment unstable, and it reduces the effectiveness of BIT. The conventional false alarm suppression methods such as repeated test and majority voting cannot meet the requirement for a complicated system, and the intelligence algorithms such as artificial neural networks (ANN) are widely studied and used. However, false alarm has a very low frequency and small sample, yet a method based on ANN requires a large size of training sample. To recognize the false alarm, we propose a method based on multi-classification support vector machine (SVM) in this paper. Firstly, we divide the state of a system into three states: healthy, false-alarm, and faulty. Then we use multi-classification with '1 vs 1' policy to train and recognize the state of a system. Finally, an example of fault injection system is taken to verify the effectiveness of the proposed method by comparing ANN. The result shows that the method is reasonable and effective.

Keywords: false alarm, fault diagnosis, SVM, k-means, BIT

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Authors: Dalma Dojcsák, Csaba Váradi, Flóra Farkas, Tamás Farkas, János Papp, Béla Viskolcz

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Background: Appendicitis is a common acute inflammatory condition in both children and adults, but current laboratory markers such as C-reactive protein (CRP), white blood cell count (WBC), absolute neutrophil count (ANC), and red blood cell count (RNC) lack specificity in detecting appendicitis-related inflammation. N-glycosylation, an asparagine-linked glycosylation process, plays a vital role in cellular interactions, angiogenesis, immune response, and effector functions. Altered N-glycosylation impacts tumor growth and both acute and chronic inflammatory processes. IgG, the second most abundant glycoprotein in serum, shows altered glycosylation patterns during inflammation, suggesting that IgG glycan modifications may serve as potential biomarkers for appendicitis. Specifically, increased levels of agalactosylated IgG glycans are a known feature of various inflammatory conditions, potentially including appendicitis. Identifying pediatric appendicitis remains challenging due to the absence of specific biomarkers, which makes diagnosis reliant on clinical symptoms, imaging such as ultrasound, and nonspecific lab indicators (e.g., CRP, WBC, ANC). In this study, we analyzed the IgG derived N-glycome in pediatric patients with appendicitis compared with healthy controls. Methodology: The N-glycome was analyzed by high-performance liquid-chromatography combined with mass spectrometry. IgG was isolated from serum samples by Protein G column. The IgG derived glycans were released by enzymatic deglycosylation and fluorescent tags were attached to each glycan moiety, which made necessitates the sample clean-up for further reliable quantitation. Overall, 38 controls and 40 serum samples diagnosed with pediatric appendicitis were analyzed by HILIC-MS methods. Multivariate statistical tests were performed with area percentage under the peak data derived from the integrated peaks, which were obtained from the chromatograms. Conclusions: Our results represented the altered N-glycome of IgG in pediatric appendicitis is similar with other observations. The glycosylation pattern reported so far for IgG is characterized by decreased galactosylation and sialylation, and an increase in fucosylation.

Keywords: N-glycosylation, liquid chromatography, mass spectrometry, inflammation, appendicitis, immunoglobulin G

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Authors: Mahmoud Enayati, Sirous Mohammadi

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In this paper, a novel procedure to find the firing angles of the multilevel inverters of supply voltage and, consequently, to decline the total harmonic distortion (THD), has been presented. In order to eliminate more harmonics in the multilevel inverters, its number of levels can be lessened or pulse width modulation waveform, in which more than one switching occur in each level, be used. Both cases complicate the non-algebraic equations and their solution cannot be performed by the conventional methods for the numerical solution of nonlinear equations such as Newton-Raphson method. In this paper, Cuckoo algorithm is used to compute the optimal firing angle of the pulse width modulation voltage waveform in the multilevel inverter. These angles should be calculated in such a way that the voltage amplitude of the fundamental frequency be generated while the total harmonic distortion of the output voltage be small. The simulation and theoretical results for the 9-levels inverter offer the high applicability of the proposed algorithm to identify the suitable firing angles for declining the low order harmonics and generate a waveform whose total harmonic distortion is very small and it is almost a sinusoidal waveform.

Keywords: evolutionary algorithms, multilevel inverters, total harmonic content, Cuckoo Algorithm

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Authors: Aaron Huber, Manoj Karwa

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Floods, heat waves, drought, wildfires, tornadoes and other environmental disasters are a snapshot of looming national problems that can create increasing demands on the national grid. With nearly 500,000 school buses on the road and the environmental protection agency (EPA) providing nearly $1B for electric school buses, there is a solution for this national issue. Bidirectional batteries in electric school buses enable a future proof solution to sustain the power grid during adverse environmental conditions and other periods of high demand. School buses have larger batteries than standard electric vehicles. When they are not transporting students, these buses can spend peak solar hours parked and plugged into bi-directional direct current fast chargers (DCFC). A partnership with Highland Electric, Proterra and Rhombus enabled over 7 MWh of energy servicing Massachusetts and Vermont grids. The buses were part of a vehicle to grid (V2G) program with National Grid and Green Mountain Power that can charge an average American home for one month with a single bus. V2G infrastructure enables school systems to future proof their charging strategies, strengthen their local grids and can create additional revenue streams with their EV fleets. A bidirectional ecosystem with Highland, Proterra and Rhombus can enable grid resiliency or the ability to withstand power outages caused by excessive demands, natural disasters or rogue nation's attacks with no loss of service. A fleet of school buses is a standalone resilient asset that can be accessed across a city to keep its citizens safe without having any toxic fumes. Nearly 95% of all school buses across USA are powered by diesel internal combustion engines. Diesel exhaust has been classified as a human carcinogen, and it can lead to and exacerbate respiratory conditions. Bidirectional school buses and chargers enable energy justice by providing backup power in case of emergencies or high demand for marginalized communities and aim to make energy more accessible, affordable, clean, and democratically managed.

Keywords: V2G, vehicle to grid, electric buses, eBuses, DC fast chargers, DCFC

Procedia PDF Downloads 77

Authors: Keke Gao, Tao Lin, Yonghui Xie, Di Zhang

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Complicated unsteady flow in axial turbines produces high-frequency unsteady aerodynamic exciting force, which threatens the safe operation of turbines. This paper illustrates how negative-bowed stator reduces the rotor unsteady aerodynamic exciting force by unsteady flow field. With the support of three-dimensional viscous compressible Navier-Stokes equation, the single axial turbines with 0, -10 and -20 degree bowed stator are comparably investigated, aiming to identify the flow field structure difference caused by various negative-bowed degrees. The results show that negative-bowed stator strengthens the turbulence kinetic energy, which is further strengthened with the increase of negative-bowed degree. Meanwhile, the flow phenomenon including stator wakes and passage vortex is shown. In addition, the interaction of upstream negative-bowed wakes contributes to the reduction of unsteady blade load fluctuation. Furthermore, the aerodynamic exciting force decreases with the increasing negative bowed degree, while the efficiency is correspondingly reduced. This paper provides the reference for the alleviation of the harmful impact caused by unsteady interaction with the method of wake control.

Keywords: unsteady flow, axial turbine, wake, aerodynamic force, loss

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Authors: Falek Kamel

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Various approaches are usually used in the dynamic analysis of beams vibrating transversally. For this, numerical methods allowing the solving of the general eigenvalue problem are utilized. The equilibrium equations describe the movement resulting from the solution of a fourth-order differential equation. Our investigation is based on the finite element method. The findings of these investigations are the vibration frequencies obtained by the Jacobi method. Two types of the elementary mass matrix are considered, representing a uniform distribution of the mass along with the element and concentrated ones located at fixed points whose number is increased progressively separated by equal distances at each evaluation stage. The studied beams have different boundary constraints representing several classical situations. Comparisons are made for beams where the distributed mass is replaced by n concentrated masses. As expected, the first calculus stage is to obtain the lowest number of beam parts that gives a frequency comparable to that issued from the Rayleigh formula. The obtained values are then compared to theoretical results based on the assumptions of the Bernoulli-Euler theory. These steps are used for the second type of mass representation in the same manner.

Keywords: structural elements, beams vibrating, dynamic analysis, finite element method, Jacobi method

Procedia PDF Downloads 165

Authors: Hamid Oumer Seid

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Piled raft foundation (PRF) is a union of pile and raft working together through the interaction of soil-pile, pile-raft, soil-raft and pile-pile to provide adequate bearing capacity and controlled settlement. A uniform pile positioning is used in PRF; however, there is a wide room for optimization through parametric study under vertical load to result in a safer and economical foundation. Addis Ababa is found in seismic zone 3 with a peak ground acceleration (PGA) above the threshold of damage, which makes investigating the performance of PRF under seismic load considering the dynamic kinematic soil structure interaction (SSI) vital. The study area is located in Addis Ababa around Mexico (commercial bank) and Kirkos (Nib, Zemen and United Bank) in which input parameters (pile length, pile diameter, pile spacing, raft area, raft thickness and load) are taken. A finite difference-based numerical software, FLAC3D V6, was used for the analysis. The Kobe (1995) and Northridge (1994) earthquakes were selected, and deconvolution analysis was done. A close load sharing between pile and raft was achieved at a spacing of 7D with different pile lengths and diameters. The maximum settlement reduction achieved is 9% for a pile of 2m diameter by increasing length from 10m to 20m, which shows pile length is not effective in reducing settlement. The installation of piles results in an increase in the negative bending moment of the raft compared with an unpiled raft. Hence, the optimized design depends on pile spacing and the raft edge length, while pile length and diameter are not significant parameters. An optimized piled raft configuration (𝐴𝐺/𝐴𝑅 = 0.25 at the center and piles provided around the edge) has reduced pile number by 40% and differential settlement by 95%. The dynamic analysis shows acceleration plot at the top of the piled raft has PGA of 0.25𝑚2/𝑠𝑒𝑐 and 0.63𝑚2/𝑠𝑒𝑐 for Northridge (1994) and Kobe (1995) earthquakes, respectively, due to attenuation of seismic waves. Pile head displacement (maximum is 2mm, and it is under the allowable limit) is affected by the PGA rather than the duration of an earthquake. End bearing and friction PRF performed similarly under two different earthquakes except for their vertical settlement considering SSI. Hence, PRF has shown adequate resistance to seismic loads.

Keywords: FLAC3D V6, earthquake, optimized piled raft foundation, pile head department

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Authors: Mina Rouhollahi, J. Boland

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Changes in cities’ heat balance due to rapid urbanization and the urban heat island (UHI) have increased energy demands for space cooling and have resulted in uncomfortable living conditions for urban residents. Climate resilience and comfortable living spaces can be addressed through well-designed urban development. The sustainable housing can be more effective in controlling high levels of urban heat. In Australia, to mitigate the effects of UHIs and summer heat waves, one solution to sustainable housing has been the trend to compact housing design and the construction of energy efficient dwellings. This paper analyses whether current housing configurations and orientations are effective in avoiding increased demands for air conditioning and having an energy efficient residential neighborhood. A significant amount of energy is consumed to ensure thermal comfort in houses. This paper reports on the modelling of heat transfer within the homes using the measurements of radiation, convection and conduction between exterior/interior wall surfaces and outdoor/indoor environment respectively. The simulation was tested on selected 7.5-star energy efficient houses constructed of typical material elements and insulation in Adelaide, Australia. The chosen design dwellings were analyzed in extremely hot weather through one year. The data were obtained via a thermal circuit to accurately model the fundamental heat transfer mechanisms on both boundaries of the house and through the multi-layered wall configurations. The formulation of the Lumped capacitance model was considered in discrete time steps by adopting a non-linear model method. The simulation results focused on the effects of orientation of the solar radiation on the dynamic thermal characteristics of the houses orientations. A high star rating did not necessarily coincide with a decrease in peak demands for cooling. A more effective approach to avoid increasing the demands for air conditioning and energy may be to integrate solar–climatic data to evaluate the performance of energy efficient houses.

Keywords: energy-efficient residential building, heat transfer, neighborhood orientation, solar–climatic data

Procedia PDF Downloads 133

Authors: Farida Eid, Hala Nasseif, Hana Mokhtar, Labib Riachi, Mudhar Hasan

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Bladder Endometriosis is a rare form of endometriosis and is defined as the presence of endometriotic tissue in the detrusor muscle of the bladder, either in full or partial thickness. Women typically present with dysuria, urinary frequency, hematuria, and recurrent urinary tract infections. Bladder endometriosis is typically found at the bladder base and bladder dome. Transvaginal ultrasound is considered first-line imaging, and the condition is typically managed with laparoscopic partial cystectomy. A 33-year-old nulliparous woman presented with chronic pelvic pain, severe dysmenorrhea, and metrorrhagia. The patient was previously diagnosed with bladder endometriomas two years ago with multiple recurrences. MRI revealed urinary bladder endometriosis measuring 3 x 2 x 1.5 cm. Accordingly, the patient underwent a cystoscopy-guided robotic-assisted excision of the endometriotic implant in the bladder with cystotomy and repair of the bladder mucosa. The operation was tolerated well, and the postoperative period was uneventful. Bladder Endometriosis (BE) typically presents with urinary symptoms and can be mistaken for a bladder tumor upon further imaging. The case was successfully managed with cystoscopy-guided, robotic-assisted excision and fulguration of the endometriotic implant in the bladder.

Keywords: endometriosis, bladder endometriosis (BE), urinary tract endometriosis (UTE), robotic-assisted surgery

Procedia PDF Downloads 32