Search results for: single inductor multi output (SIMO)
8626 Assessment of Genotoxic Effects of a Fungicide (Propiconazole) in Freshwater Fish Gambusia Affinis Using Alkaline Single-Cell Gel Electrophoresis (Comet Essay)
Authors: Bourenane Bouhafs Naziha
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ARTEA330EC is a fungicide used to inhibit the growth of many types of fungi on and cereals and rice, it is the single largest selling agrochemical that has been widely detected in surface waters in our area (Northeast Algerian). The studies on long-term genotoxic effects of fugicides in different tissues of fish using genotoxic biomarkers are limited. Therefore, in the present study DNA damage by propiconazole in freshwater fish Gambusia affinis by comet assays was investigated. The LC(50)- 96 h of the fungicide was estimated for the fish in a semi-static system. On this basis of LC(50) value sublethal and nonlethal concentrations were determined (25; 50; 75; and 100 ppm). The DNA damage was measured in erythrocytes as the percentage of DNA in comet tails of fishes exposed to above concentrations the fungicide. In general,non significant effects for both the concentrations and time of exposure were observed in treated fish compared with the controls. However It was found that the highest DNA damage was observed at the highest concentration and the longest time of exposure (day 12). The study indicated comet assay to be sensitive and rapid method to detect genotoxicity of propiconasol and other pesticides in fishes.Keywords: genotoxicity, fungicide, propiconazole, freshwater, Gambusia affinis, alkaline single-cell gel electrophoresis
Procedia PDF Downloads 2988625 Stakeholder Perceptions of Environmental, Social, and Governance Reporting Patterns: A Multi-Method Study
Authors: Samrina Jafrin, Till Talaulicar
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This study investigates stakeholder perceptions of environmental, social, and governance (ESG) reporting patterns and their effectiveness in enhancing trust and transparency. Utilizing a multi-method approach, including experimental research and systematic literature review, insights are gathered from investors, employees, customers, suppliers, managers, and community members. The findings reveal diverse stakeholder expectations and perceptions and emphasize the importance of effective ESG reporting strategies in building credibility and trust. This research contributes to the academic discourse on corporate sustainability reporting and provides practical recommendations for optimizing ESG reporting practices.Keywords: ESG reporting, stakeholder perceptions, corporate sustainability, transparency, trust
Procedia PDF Downloads 198624 Thermodynamic Evaluation of Coupling APR-1400 with a Thermal Desalination Plant
Authors: M. Gomaa Abdoelatef, Robert M. Field, Lee, Yong-Kwan
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Growing human populations have placed increased demands on water supplies and a heightened interest in desalination infrastructure. Key elements of the economics of desalination projects are thermal and electrical inputs. With growing concerns over the use of fossil fuels to (indirectly) supply these inputs, coupling of desalination with nuclear power production represents a significant opportunity. Individually, nuclear and desalination technologies have a long history and are relatively mature. For desalination, Reverse Osmosis (RO) has the lowest energy inputs. However, the economically driven output quality of the water produced using RO, which uses only electrical inputs, is lower than the output water quality from thermal desalination plants. Therefore, modern desalination projects consider that RO should be coupled with thermal desalination technologies (MSF, MED, or MED-TVC) with attendant steam inputs to permit blending to produce various qualities of water. A large nuclear facility is well positioned to dispatch large quantities of both electrical and thermal power. This paper considers the supply of thermal energy to a large desalination facility to examine heat balance impact on the nuclear steam cycle. The APR1400 nuclear plant is selected as prototypical from both a capacity and turbine cycle heat balance perspective to examine steam supply and the impact on electrical output. Extraction points and quantities of steam are considered parametrically along with various types of thermal desalination technologies to form the basis for further evaluations of economically optimal approaches to the interface of nuclear power production with desalination projects. In our study, the thermodynamic evaluation will be executed by DE-TOP which is the IAEA desalination program, it is approved to be capable of analyzing power generation systems coupled to desalination systems through various steam extraction positions, taking into consideration the isolation loop between the APR-1400 and the thermal desalination plant for safety concern.Keywords: APR-1400, desalination, DE-TOP, IAEA, MSF, MED, MED-TVC, RO
Procedia PDF Downloads 5338623 Theoretical Performance of a Sustainable Clean Energy On-Site Generation Device to Convert Consumers into Producers and Its Possible Impact on Electrical National Grids
Authors: Eudes Vera
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In this paper, a theoretical evaluation is carried out of the performance of a forthcoming fuel-less clean energy generation device, the Air Motor. The underlying physical principles that support this technology are succinctly described. Examples of the machine and theoretical values of input and output powers are also given. In addition, its main features like portability, on-site energy generation and delivery, miniaturization of generation plants, efficiency, and scaling down of the whole electric infrastructure are discussed. The main component of the Air Motor, the Thermal Air Turbine, generates useful power by converting in mechanical energy part of the thermal energy contained in a fan-produced airflow while leaving intact its kinetic energy. Due to this fact an air motor can contain a long succession of identical air turbines and the total power generated out of a single airflow can be very large, as well as its mechanical efficiency. It is found using the corresponding formulae that the mechanical efficiency of this device can be much greater than 100%, while its thermal efficiency is always less than 100%. On account of its multiple advantages, the Air Motor seems to be the perfect device to convert energy consumers into energy producers worldwide. If so, it would appear that current national electrical grids would no longer be necessary, because it does not seem practical or economical to bring the energy from far-away distances while it can be generated and consumed locally at the consumer’s premises using just the thermal energy contained in the ambient air.Keywords: electrical grid, clean energy, renewable energy, in situ generation and delivery, generation efficiency
Procedia PDF Downloads 1758622 A Slip Transmission through Alpha/Beta Boundaries in a Titanium Alloy (Ti-6Al-4V)
Authors: Rayan B. M. Ameen, Ian P. Jones, Yu Lung Chiu
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Single alpha-beta colony micro-pillars have been manufactured from a polycrystalline commercial Ti-6Al-4V sample using Focused Ion Beam (FIB). Each pillar contained two alpha lamellae separated by a thin fillet of beta phase. A nano-indenter was then used to conduct uniaxial micro-compression tests on Ti alloy single crystals, using a diamond flat tip as a compression platen. By controlling the crystal orientation along the micro-pillar using Electron back scattering diffraction (EBSD) different slip systems have been selectively activated. The advantage of the micro-compression method over conventional mechanical testing techniques is the ability to localize a single crystal volume which is characterizable after deformation. By matching the stress-strain relations resulting from micro-compression experiments to TEM (Transmission Electron Microscopy) studies of slip transmission mechanisms through the α-β interfaces, some proper constitutive material parameters such as the role of these interfaces in determining yield, strain-hardening behaviour, initial dislocation density and the critical resolved shear stress are suggested.Keywords: α/β-Ti alloy, focused ion beam, micro-mechanical test, nano-indentation, transmission electron diffraction, plastic flow
Procedia PDF Downloads 3868621 Continuous-Time Analysis And Performance Assessment For Digital Control Of High-Frequency Switching Synchronous Dc-Dc Converter
Authors: Rihab Hamdi, Amel Hadri Hamida, Ouafae Bennis, Sakina Zerouali
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This paper features a performance analysis and robustness assessment of a digitally controlled DC-DC three-cell buck converter associated in parallel, operating in continuous conduction mode (CCM), facing feeding parameters variation and loads disturbance. The control strategy relies on the continuous-time with an averaged modeling technique for high-frequency switching converter. The methodology is to modulate the complete design procedure, in regard to the existence of an instantaneous current operating point for designing the digital closed-loop, to the same continuous-time domain. Moreover, the adopted approach is to include a digital voltage control (DVC) technique, taking an account for digital control delays and sampling effects, which aims at improving efficiency and dynamic response and preventing generally undesired phenomena. The results obtained under load change, input change, and reference change clearly demonstrates an excellent dynamic response of the proposed technique, also as provide stability in any operating conditions, the effectiveness is fast with a smooth tracking of the specified output voltage. Simulations studies in MATLAB/Simulink environment are performed to verify the concept.Keywords: continuous conduction mode, digital control, parallel multi-cells converter, performance analysis, power electronics
Procedia PDF Downloads 1528620 An Integrated Intuitionistic Fuzzy Elimination Et Choix Traduisant La REalite (IFELECTRE) Model
Authors: Babak Daneshvar Rouyendegh
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The aim of this study is to develop and describe a new methodology for the Multi-Criteria Decision-Making (MCDM) problem using Intuitionistic Fuzzy Elimination Et Choix Traduisant La REalite (IFELECTRE) model. The proposed models enable Decision-Makers (DMs) on the assessment and use Intuitionistic Fuzzy numbers (IFN). A numerical example is provided to demonstrate and clarify the proposed analysis procedure. Also, an empirical experiment is conducted to validation the effectiveness.Keywords: Decision-Makers (DMs), Multi-Criteria Decision-Making (MCDM), Intuitionistic Fuzzy Elimination Et Choix Traduisant La REalite (IFELECTRE), Intuitionistic Fuzzy Numbers (IFN)
Procedia PDF Downloads 6798619 Nafion Nanofiber Mat in a Single Fuel Cell Test
Authors: Chijioke Okafor, Malik Maaza, Touhami Mokrani
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Proton exchange membrane, PEM was developed and tested for potential application in fuel cell. Nafion was electrospun to nanofiber network with the aid of poly(ethylene oxide), PEO, as a carrier polymer. The matrix polymer was crosslinked with Norland Optical Adhesive 63 under UV after compacting and annealing. The welded nanofiber mat was characterized for morphology, proton conductivity, and methanol permeability, then tested in a single cell test station. The results of the fabricated nanofiber membrane showed a proton conductivity of 0.1 S/cm at 25 oC and higher fiber volume fraction; methanol permeability of 3.6x10^-6 cm2/s and power density of 96.1 and 81.2 mW/cm2 for 5M and 1M methanol concentration respectively.Keywords: fuel cell, nafion, nanofiber, permeability
Procedia PDF Downloads 4828618 Coupling of Two Discretization Schemes for the Lattice Boltzmann Equation
Authors: Tobias Horstmann, Thomas Le Garrec, Daniel-Ciprian Mincu, Emmanuel Lévêque
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Despite the efficiency and low dissipation of the stream-collide formulation of the Lattice Boltzmann (LB) algorithm, which is nowadays implemented in many commercial LBM solvers, there are certain situations, e.g. mesh transition, in which a classical finite-volume or finite-difference formulation of the LB algorithm still bear advantages. In this paper, we present an algorithm that combines the node-based streaming of the distribution functions with a second-order finite volume discretization of the advection term of the BGK-LB equation on a uniform D2Q9 lattice. It is shown that such a coupling is possible for a multi-domain approach as long as the overlap, or buffer zone, between two domains, is achieved on at least 2Δx. This also implies that a direct coupling (without buffer zone) of a stream-collide and finite-volume LB algorithm on a single grid is not stable. The critical parameter in the coupling is the CFL number equal to 1 that is imposed by the stream-collide algorithm. Nevertheless, an explicit filtering step on the finite-volume domain can stabilize the solution. In a further investigation, we demonstrate how such a coupling can be used for mesh transition, resulting in an intrinsic conservation of mass over the interface.Keywords: algorithm coupling, finite volume formulation, grid refinement, Lattice Boltzmann method
Procedia PDF Downloads 3808617 Integration of a Load Switch with DC/DC Buck Converter for Power Distribution in Low Cost Educational Nanosatellite
Authors: Bentoutou Houari, Boutte Aissa, Belaidi El Yazid, Limam Lakhdar
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The integration of a load switch with a DC/DC buck converter using LM2596 for power distribution in low-cost educational nanosatellites is a technique that aims to efficiently manage the power distribution system in these small spacecraft. The converter is based on the LM2596 regulator and designed to step down the input voltage of +16.8V to +12V, +5V, and +3.3V output, which are suitable for the nanosatellite's various subsystems. The load switch is based on MOSFET and is used to turn on or off the power supply to a particular load and protect the nanosatellite from power surges. A prototype of a +12V DC/DC buck converter with a high side load switch has been realized and tested, which meets our requirements and shows a good efficiency of 89%. In addition, the prototype features a capacitor between the source and gate of the MOSFET, which has effectively reduced the inrush current, demonstrating the effectiveness of this approach in reducing surges of current when the load is connected. The output current and voltage were measured at 0.7A and 11.89V, respectively, making this design suitable for use in low-cost educational nanosatellites.Keywords: DC/DC buck converter, load switch, LM2596, electrical power subsystems, nanosatellite, inrush current
Procedia PDF Downloads 1018616 Air Conditioning Variation of 1kW Open-Cathode Proton Exchange Membrane (PEM) Fuel Cell
Authors: Mohammad Syahirin Aisha, Khairul Imran Sainan
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The PEM fuel cell is a device that generate electric by electrochemical reaction between hydrogen fuel and oxygen in the fuel cell stack. PEM fuel cell consists of an anode (hydrogen supply), a cathode (oxygen supply) and an electrolyte that allow charges move between the two positions of the fuel cell. The only product being developed after the reaction is water (H2O) and heat as the waste which does not emit greenhouse gasses. The performance of fuel cell affected by numerous parameters. This study is restricted to cathode parameters that affect fuel cell performance. At the anode side, the reactant is not going through any changes. Experiments with variation in air velocity (3m/s, 6m/s and 9m/s), temperature (10oC, 20oC, 35oC) and relative humidity (50%, 60%, and 70%) have been carried out. The experiments results are presented in the form of fuel cell stack power output over time, which demonstrate the impacts of the various air condition on the execution of the PEM fuel cell. In this study, the experimental analysis shows that with variation of air conditions, it gives different fuel cell performance behavior. The maximum power output of the experiment was measured at an ambient temperature of 25oC with relative humidity and 9m/s velocity of air.Keywords: air-breathing PEM fuel cell, cathode side, performance, variation in air condition
Procedia PDF Downloads 4638615 Study on the Seismic Response of Slope under Pulse-Like Ground Motion
Authors: Peter Antwi Buah, Yingbin Zhang, Jianxian He, Chenlin Xiang, Delali Atsu Y. Bakah
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Near-fault ground motions with velocity pulses are considered to cause significant damage to structures or slopes compared to ordinary ground motions without velocity pulses. The double pulsed pulse-like ground motion is as well known to be stronger than the single pulse. This study has numerically justified this perspective by studying the dynamic response of a homogeneous rock slope subjected to four pulse-like and two non-pulse-like ground motions using the Fast Lagrangian Analysis of Continua in 3 Dimensions (FLAC3D) software. Two of the pulse-like ground motions just have a single pulse. The results show that near-fault ground motions with velocity pulses can cause a higher dynamic response than regular ground motions. The amplification of the peak ground acceleration (PGA) in horizontal direction increases with the increase of the slope elevation. The seismic response of the slope under double pulse ground motion is stronger than that of the single pulse ground motion. The PGV amplification factor under the effect of the non-pulse-like records is also smaller than those under the pulse-like records. The velocity pulse strengthens the earthquake damage to the slope, which results in producing a more strong dynamic response.Keywords: velocity pulses, dynamic response, PGV magnification effect, elevation effect, double pulse
Procedia PDF Downloads 1778614 Neurophysiology of Domain Specific Execution Costs of Grasping in Working Memory Phases
Authors: Rumeysa Gunduz, Dirk Koester, Thomas Schack
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Previous behavioral studies have shown that working memory (WM) and manual actions share limited capacity cognitive resources, which in turn results in execution costs of manual actions in WM. However, to the best of our knowledge, there is no study investigating the neurophysiology of execution costs. The current study aims to fill this research gap investigating the neurophysiology of execution costs of grasping in WM phases (encoding, maintenance, retrieval) considering verbal and visuospatial domains of WM. A WM-grasping dual task paradigm was implemented to examine execution costs. Baseline single task required performing verbal or visuospatial version of a WM task. Dual task required performing the WM task embedded in a high precision grasp to place task. 30 participants were tested in a 2 (single vs. dual task) x 2 (visuo-spatial vs. verbal WM) within subject design. Event related potentials (ERPs) were extracted for each WM phase separately in the single and dual tasks. Memory performance for visuospatial WM, but not for verbal WM, was significantly lower in the dual task compared to the single task. Encoding related ERPs in the single task revealed different ERPs of verbal WM and visuospatial WM at bilateral anterior sites and right posterior site. In the dual task, bilateral anterior difference disappeared due to bilaterally increased anterior negativities for visuospatial WM. Maintenance related ERPs in the dual task revealed different ERPs of verbal WM and visuospatial WM at bilateral posterior sites. There was also anterior negativity for visuospatial WM. Retrieval related ERPs in the single task revealed different ERPs of verbal WM and visuospatial WM at bilateral posterior sites. In the dual task, there was no difference between verbal WM and visuospatial WM. Behavioral and ERP findings suggest that execution of grasping shares cognitive resources only with visuospatial WM, which in turn results in domain specific execution costs. Moreover, ERP findings suggest unique patterns of costs in each WM phase, which supports the idea that each WM phase reflects a separate cognitive process. This study not only contributes to the understanding of cognitive principles of manual action control, but also contributes to the understanding of WM as an entity consisting of separate modalities and cognitive processes.Keywords: dual task, grasping execution, neurophysiology, working memory domains, working memory phases
Procedia PDF Downloads 4288613 A Proposal for U-City (Smart City) Service Method Using Real-Time Digital Map
Authors: SangWon Han, MuWook Pyeon, Sujung Moon, DaeKyo Seo
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Recently, technologies based on three-dimensional (3D) space information are being developed and quality of life is improving as a result. Research on real-time digital map (RDM) is being conducted now to provide 3D space information. RDM is a service that creates and supplies 3D space information in real time based on location/shape detection. Research subjects on RDM include the construction of 3D space information with matching image data, complementing the weaknesses of image acquisition using multi-source data, and data collection methods using big data. Using RDM will be effective for space analysis using 3D space information in a U-City and for other space information utilization technologies.Keywords: RDM, multi-source data, big data, U-City
Procedia PDF Downloads 4348612 Understanding Neuronal and Glial Cell Behaviour in Multi-Layer Nanofibre Systems to Support the Development of an in vitro Model of Spinal Cord Injury and Personalised Prostheses for Repair
Authors: H. Pegram, R. Stevens, L. De Girolamo
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Aligned electrospun nanofibres act as effective neuronal and glial cell scaffolds that can be layered to contain multiple sheets harboring different cell populations. This allows personalised biofunctional prostheses to be manufactured with both acellular and cellularised layers for the treatment of spinal cord injury. Additionally, the manufacturing route may be configured to produce in-vitro 3D cell based model of spinal cord injury to aid drug development and enhance prosthesis performance. The goal of this investigation was to optimise the multi-layer scaffold design parameters for prosthesis manufacture, to enable the development of multi-layer patient specific implant therapies. The work has also focused on the fabricating aligned nanofibre scaffolds that promote in-vitro neuronal and glial cell population growth, cell-to-cell interaction and long-term survival following trauma to mimic an in-vivo spinal cord lesion. The approach has established reproducible lesions and has identified markers of trauma and regeneration marked by effective neuronal migration across the lesion with glial support. The investigation has advanced the development of an in-vitro model of traumatic spinal cord injury and has identified a route to manufacture prostheses which target the repair spinal cord injury. Evidence collated to investigate the multi-layer concept suggests that physical cues provided by nanofibres provide both a natural extra-cellular matrix (ECM) like environment and controls cell proliferation and migration. Specifically, aligned nanofibre layers act as a guidance system for migrating and elongating neurons. On a larger scale, material type in multi-layer systems also has an influence in inter-layer migration as cell types favour different material types. Results have shown that layering nanofibre membranes create a multi-level scaffold system which can enhance or prohibit cell migration between layers. It is hypothesised that modifying nanofibre layer material permits control over neuronal/glial cell migration. Using this concept, layering of neuronal and glial cells has become possible, in the context of tissue engineering and also modelling in-vitro induced lesions.Keywords: electrospinning, layering, lesion, modeling, nanofibre
Procedia PDF Downloads 1388611 Multi-Layer Perceptron and Radial Basis Function Neural Network Models for Classification of Diabetic Retinopathy Disease Using Video-Oculography Signals
Authors: Ceren Kaya, Okan Erkaymaz, Orhan Ayar, Mahmut Özer
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Diabetes Mellitus (Diabetes) is a disease based on insulin hormone disorders and causes high blood glucose. Clinical findings determine that diabetes can be diagnosed by electrophysiological signals obtained from the vital organs. 'Diabetic Retinopathy' is one of the most common eye diseases resulting on diabetes and it is the leading cause of vision loss due to structural alteration of the retinal layer vessels. In this study, features of horizontal and vertical Video-Oculography (VOG) signals have been used to classify non-proliferative and proliferative diabetic retinopathy disease. Twenty-five features are acquired by using discrete wavelet transform with VOG signals which are taken from 21 subjects. Two models, based on multi-layer perceptron and radial basis function, are recommended in the diagnosis of Diabetic Retinopathy. The proposed models also can detect level of the disease. We show comparative classification performance of the proposed models. Our results show that proposed the RBF model (100%) results in better classification performance than the MLP model (94%).Keywords: diabetic retinopathy, discrete wavelet transform, multi-layer perceptron, radial basis function, video-oculography (VOG)
Procedia PDF Downloads 2608610 Effect of CYP2B6 c.516G>T and c.983T>C Single Nucleotide Polymorphisms on Plasma Nevirapine Levels in Zimbabwean HIV/AIDS Patients
Authors: Doreen Duri, Danai Zhou, Babil Stray-Pedersen, Collet Dandara
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Given the high prevalence of HIV/AIDS in sub-Saharan Africa, and the elusive search for a cure, understanding the pharmacogenetics of currently used drugs is critical in populations from the most affected regions. Compared to Asian and Caucasian populations, African population groups are more genetically diverse, making it difficult to extrapolate findings from one ethnic group to another. This study aimed to investigate the role of genetic variation in CYP2B6 (c.516G>T and c.983T>C) single nucleotide polymorphisms on plasma nevirapine levels among HIV-infected adult Zimbabwean patients. Using a cross-sectional study, patients on nevirapine-containing HAART, having reached steady state (more than six weeks on treatment) were recruited to participate. Blood samples were collected after patients provided consent and samples were used to extract DNA for genetic analysis or to measure plasma nevirapine levels. Genetic analysis was carried out using PCR and RFLP or Snapshot for the two single nucleotide polymorphisms; CYP2B6 c.516G>T and c.983T>C, while LC-MS/MS was used in analyzing nevirapine concentration. CYP2B6 c.516G>T and c.983T>C significantly predicted plasma nevirapine concentration with the c.516T and c.983T being associated with elevated plasma nevirapine concentrations. Comparisons of the variant allele frequencies observed in this group to those reported in some African, Caucasian and Asian populations showed significant differences. We conclude that pharmacogenetics of nevirapine can be creatively used to determine patients who are likely to develop nevirapine-associated side effects as well as too low plasma concentrations for viral suppression.Keywords: allele frequencies, genetically diverse, nevirapine, single nucleotide polymorphism
Procedia PDF Downloads 4568609 A Study on Long Life Hybrid Battery System Consists of Ni-63 Betavoltaic Battery and All Solid Battery
Authors: Bosung Kim, Youngmok Yun, Sungho Lee, Chanseok Park
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There is a limitation to power supply and operation by the chemical or physical battery in the space environment. Therefore, research for utilizing nuclear energy in the universe has been in progress since the 1950s, around the major industrialized countries. In this study, the self-rechargeable battery having a long life relative to the half-life of the radioisotope is suggested. The hybrid system is composed of betavoltaic battery, all solid battery and energy harvesting board. Betavoltaic battery can produce electrical power at least 10 years over using the radioisotope from Ni-63 and the silicon-based semiconductor. The electrical power generated from the betavoltaic battery is stored in the all-solid battery and stored power is used if necessary. The hybrid system board is composed of input terminals, boost circuit, charging terminals and output terminals. Betavoltaic and all solid batteries are connected to the input and output terminal, respectively. The electric current of 10 µA is applied to the system board by using the high-resolution power simulator. The system efficiencies are measured from a boost up voltage of 1.8 V, 2.4 V and 3 V, respectively. As a result, the efficiency of system board is about 75% after boosting up the voltage from 1V to 3V.Keywords: isotope, betavoltaic, nuclear, battery, energy harvesting
Procedia PDF Downloads 3288608 Selection and Preparation of High Performance, Natural and Cost-Effective Hydrogel as a Bio-Ink for 3D Bio-Printing and Organ on Chip Applications
Authors: Rawan Ashraf, Ahmed E. Gomaa, Gehan Safwat, Ayman Diab
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Background: Three-dimensional (3D) bio-printing has become a versatile and powerful method for generating a variety of biological constructs, including bone or extracellular matrix scaffolds endo- or epithelial, muscle tissue, as well as organoids. Aim of the study: Fabricate a low cost DIY 3D bio-printer to produce 3D bio-printed products such as anti-microbial packaging or multi-organs on chips. We demonstrate the alignment between two types of 3D printer technology (3D Bio-printer and DLP) on Multi-organ-on-a-chip (multi-OoC) devices fabrication. Methods: First, Design and Fabrication of the Syringe Unit for Modification of an Off-the-Shelf 3D Printer, then Preparation of Hydrogel based on natural polymers Sodium Alginate and Gelatin, followed by acquisition of the cell suspension, then modeling the desired 3D structure. Preparation for 3D printing, then Cell-free and cell-laden hydrogels went through the printing process at room temperature under sterile conditions and finally post printing curing process and studying the printed structure regards physical and chemical characteristics. The hard scaffold of the Organ on chip devices was designed and fabricated using the DLP-3D printer, following similar approaches as the Microfluidics system fabrication. Results: The fabricated Bio-Ink was based onHydrogel polymer mix of sodium alginate and gelatin 15% to 0.5%, respectively. Later the 3D printing process was conducted using a higher percentage of alginate-based hydrogels because of it viscosity and the controllable crosslinking, unlike the thermal crosslinking of Gelatin. The hydrogels were colored to simulate the representation of two types of cells. The adaption of the hard scaffold, whether for the Microfluidics system or the hard-tissues, has been acquired by the DLP 3D printers with fabricated natural bioactive essential oils that contain antimicrobial activity, followed by printing in Situ three complex layers of soft-hydrogel as a cell-free Bio-Ink to simulate the real-life tissue engineering process. The final product was a proof of concept for a rapid 3D cell culturing approaches that uses an engineered hard scaffold along with soft-tissues, thus, several applications were offered as products of the current prototype, including the Organ-On-Chip as a successful integration between DLP and 3D bioprinter. Conclusion: Multiple designs for the organ-on-a-chip (multi-OoC) devices have been acquired in our study with main focus on the low cost fabrication of such technology and the potential to revolutionize human health research and development. We describe circumstances in which multi-organ models are useful after briefly examining the requirement for full multi-organ models with a systemic component. Following that, we took a look at the current multi-OoC platforms, such as integrated body-on-a-chip devices and modular techniques that use linked organ-specific modules.Keywords: 3d bio-printer, hydrogel, multi-organ on chip, bio-inks
Procedia PDF Downloads 1768607 Pseudo Modal Operating Deflection Shape Based Estimation Technique of Mode Shape Using Time History Modal Assurance Criterion
Authors: Doyoung Kim, Hyo Seon Park
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Studies of System Identification(SI) based on Structural Health Monitoring(SHM) have actively conducted for structural safety. Recently SI techniques have been rapidly developed with output-only SI paradigm for estimating modal parameters. The features of these output-only SI methods consist of Frequency Domain Decomposition(FDD) and Stochastic Subspace Identification(SSI) are using the algorithms based on orthogonal decomposition such as singular value decomposition(SVD). But the SVD leads to high level of computational complexity to estimate modal parameters. This paper proposes the technique to estimate mode shape with lower computational cost. This technique shows pseudo modal Operating Deflections Shape(ODS) through bandpass filter and suggests time history Modal Assurance Criterion(MAC). Finally, mode shape could be estimated from pseudo modal ODS and time history MAC. Analytical simulations of vibration measurement were performed and the results with mode shape and computation time between representative SI method and proposed method were compared.Keywords: modal assurance criterion, mode shape, operating deflection shape, system identification
Procedia PDF Downloads 4118606 Studying on Pile Seismic Operation with Numerical Method by Using FLAC 3D Software
Authors: Hossein Motaghedi, Kaveh Arkani, Siavash Salamatpoor
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Usually the piles are important tools for safety and economical design of high and heavy structures. For this aim the response of single pile under dynamic load is so effective. Also, the agents which have influence on single pile response are properties of pile geometrical, soil and subjected loads. In this study the finite difference numerical method and by using FLAC 3D software is used for evaluation of single pile behavior under peak ground acceleration (PGA) of El Centro earthquake record in California (1940). The results of this models compared by experimental results of other researchers and it will be seen that the results of this models are approximately coincide by experimental data's. For example the maximum moment and displacement in top of the pile is corresponding to the other experimental results of pervious researchers. Furthermore, in this paper is tried to evaluate the effective properties between soil and pile. The results is shown that by increasing the pile diagonal, the pile top displacement will be decreased. As well as, by increasing the length of pile, the top displacement will be increased. Also, by increasing the stiffness ratio of pile to soil, the produced moment in pile body will be increased and the taller piles have more interaction by soils and have high inertia. So, these results can help directly to optimization design of pile dimensions.Keywords: pile seismic response, interaction between soil and pile, numerical analysis, FLAC 3D
Procedia PDF Downloads 3908605 Changing Patterns of Marriage and Sexual Relations among Young Single Female Workers in Garment Factories in Gazipur, Bangladesh
Authors: Runa Laila
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In Bangladesh, migration and employment opportunities in the ready-made garment factories presented an alternative to early and arranged-marriage to many young women from the countryside. Although the positive impact of young women’s labour migration and employment in the garment industry on economic independence, increased negotiation power, and enhancement of self-esteem have been well documented, impact of employment on sexual norms and practices remained under-researched. This ethnographic study comprising of an in-depth interview of 21 single young women working in various garment factories in Gazipur, Dhaka, explores the implication of work on sexual norms and practices. This study found young single garment workers experience a range of consensual and coercive sexual relations. The mixed-sex work environment in the garment manufacturing industry and private housing arrangements provide young single women opportunities to develop romantic and sexual relationships in the transient urban space, which was more restricted in the rural areas. The use of mobile phones further aids lovers to meet in amusement parks, friends’ houses, or residential hotels beyond the gaze of colleagues and neighbors. Due to sexual double standard, men’s sexual advantage is seen as natural and accepted, while women are being blamed as immoral for being engaged in pre-marital sex. Although self-choice marriage and premarital relations reported to be common among garment workers, stigma related to premarital sex lead young single women to resort to secret abortion practices. Married men also use power position to lure women in a subordinate position in coerce sexual relations, putting their reproductive and psychological health at risk. To improve sexual and reproductive health and wellbeing of young female garment workers, it is important to understand these changing sexual practices which otherwise remain taboo in public health discourses.Keywords: female migration, ready-made garment, reproductive health, sexual practice
Procedia PDF Downloads 1878604 Solar Still Absorber Plate Modification and Exergy Analysis
Authors: Dudul Das, Pankaj Kalita, Sangeeta Borah
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Freshwater availability in the world is as low as 1% of total water available and in many geographical locations dissolved fluoride and arsenic are serious problem. In India availability of freshwater will be stressed by 2025, so the availability saline water from sea is a hope for the people of Indian sub-continent, but saline water is not drinkable it need to be processed, which again require a huge amount of energy. So the most easy and handy option in such situation for all those problems is solar still, this investigation presents various scopes for improvement of its efficiency. Experiments showed that by increasing the absorber plate area through better design can increase the distillate output by two fold and by using jute wicks in the modified absorber plate increases the output up to three times that of conventional solar still available in the Department of Energy, Tezpur University. The experiment is carried out at constant water depth of 8.5 cm and glass cover inclination of 27o facing South. The exergy analysis carried out clearly resulted that with the use of jute wick and baffle plated basin the efficiency achieved more than the simple baffle plated basin. The Instantaneous exergy without jute wick ranges from 2.5% to 4.5% while using jute it ranges from 1.5% to 5.15%.Keywords: fluoride, absorber plate, jute wick, instantaneous exergy
Procedia PDF Downloads 4648603 Optimal Emergency Shipment Policy for a Single-Echelon Periodic Review Inventory System
Authors: Saeed Poormoaied, Zumbul Atan
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Emergency shipments provide a powerful mechanism to alleviate the risk of imminent stock-outs and can result in substantial benefits in an inventory system. Customer satisfaction and high service level are immediate consequences of utilizing emergency shipments. In this paper, we consider a single-echelon periodic review inventory system consisting of a single local warehouse, being replenished from a central warehouse with ample capacity in an infinite horizon setting. Since the structure of the optimal policy appears to be complicated, we analyze this problem under an order-up-to-S inventory control policy framework, the (S, T) policy, with the emergency shipment consideration. In each period of the periodic review policy, there is a single opportunity at any point of time for the emergency shipment so that in case of stock-outs, an emergency shipment is requested. The goal is to determine the timing and amount of the emergency shipment during a period (emergency shipment policy) as well as the base stock periodic review policy parameters (replenishment policy). We show that how taking advantage of having an emergency shipment during periods improves the performance of the classical (S, T) policy, especially when fixed and unit emergency shipment costs are small. Investigating the structure of the objective function, we develop an exact algorithm for finding the optimal solution. We also provide a heuristic and an approximation algorithm for the periodic review inventory system problem. The experimental analyses indicate that the heuristic algorithm is computationally more efficient than the approximation algorithm, but in terms of the solution efficiency, the approximation algorithm performs very well. We achieve up to 13% cost savings in the (S, T) policy if we apply the proposed emergency shipment policy. Moreover, our computational results reveal that the approximated solution is often within 0.21% of the globally optimal solution.Keywords: emergency shipment, inventory, periodic review policy, approximation algorithm.
Procedia PDF Downloads 1418602 Design of Single Point Mooring Buoy System by Parametric Analysis
Authors: Chul-Hee Jo, Do-Youb Kim, Seok-Jin Cho, Yu-Ho Rho
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The Catenary Anchor Leg Mooring (CALM) Single Point Mooring (SPM) buoy system is the most popular and widely used type of offshore loading terminals. SPM buoy mooring systems have been deployed worldwide for a variety of applications, water depths and vessel sizes ranging from small production carriers to Very Large Crude Carriers (VLCCs). Because of safe and easy berthing and un-berthing operations, the SPM buoy mooring system is also preferred for offshore terminals. The SPM buoy consists of a buoy that is permanently moored to the seabed by means of multiple mooring lines. The buoy contains a bearing system that allows a part of it to rotate around the moored geostatic part. When moored to the rotating part of the buoy, a vessel is able to freely weathervane around the buoy. This study was verified the effects of design variables in order to design an SPM buoy mooring system through parametric analysis. The design variables have independent and nonlinear characteristics. Using parametric analysis, this research was found that the fairlead departure angle, wave height and period, chain diameter and line length effect to the mooring top tension, buoy excursion and line layback.Keywords: Single Point Mooring (SPM), Catenary Anchor Leg Mooring(CALM), design variables, parametric analysis, mooring system optimization
Procedia PDF Downloads 3968601 The Experience of Applying Multi-Sensory Stimulation ICU for Arousing a Patient with Traumatic Brain Injury in Intensive Care
Authors: Hsiao-Wen Tsai
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Motor vehicle accident is the first cause of head injury in the world; severe head injury cases may cause conscious disturbance and death. This is a report about a case of a young adult patient suffering from motor vehicle accident leading to severe head injury who passed through three time surgical procedures, and his mother (who is the informal caregiver). This case was followed from 28th January to 15th February 2011 by using Gordon’s 11 functional health patterns. Patient’s cognitive-perceptual and self-perception-self-concept patterns were altered. Anxiety was also noted on his informal caregiver due to patients’ condition. During the intensive care period, maintaining patient’s vital signs and cerebral perfusion pressure were essential to avoid secondary neuronal injury. Multi-sensory stimulation, caring accompanying, supporting, listening and encouraging patient’s family involved in patient care were very important to reduce informal caregiver anxiety. Finally, the patient consciousness improved from GCS 4 to GCS 11 before discharging from ICU. Patient’s primary informal caregiver, his mother, also showed anxiety improvement. This is was successful case with traumatic brain injury recovered from coma.Keywords: anxiety, multi-sensory stimulation, reduce intracranial adaptive capacity, traumatic brain injury
Procedia PDF Downloads 2698600 Investigation of a Novel Dual Band Microstrip/Waveguide Hybrid Antenna Element
Authors: Raoudane Bouziyan, Kawser Mohammad Tawhid
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Microstrip antennas are low in profile, light in weight, conformable in structure and are now developed for many applications. The main difficulty of the microstrip antenna is its narrow bandwidth. Several modern applications like satellite communications, remote sensing, and multi-function radar systems will find it useful if there is dual-band antenna operating from a single aperture. Some applications require covering both transmitting and receiving frequency bands which are spaced apart. Providing multiple antennas to handle multiple frequencies and polarizations becomes especially difficult if the available space is limited as with airborne platforms and submarine periscopes. Dual band operation can be realized from a single feed using slot loaded or stacked microstrip antenna or two separately fed antennas sharing a common aperture. The former design, when used in arrays, has certain limitations like complicated beam forming or diplexing network and difficulty to realize good radiation patterns at both the bands. The second technique provides more flexibility with separate feed system as beams in each frequency band can be controlled independently. Another desirable feature of a dual band antenna is easy adjustability of upper and lower frequency bands. This thesis presents investigation of a new dual-band antenna, which is a hybrid of microstrip and waveguide radiating elements. The low band radiator is a Shorted Annular Ring (SAR) microstrip antenna and the high band radiator is an aperture antenna. The hybrid antenna is realized by forming a waveguide radiator in the shorted region of the SAR microstrip antenna. It is shown that the upper to lower frequency ratio can be controlled by the proper choice of various dimensions and dielectric material. Operation in both linear and circular polarization is possible in either band. Moreover, both broadside and conical beams can be generated in either band from this antenna element. Finite Element Method based software, HFSS and Method of Moments based software, FEKO were employed to perform parametric studies of the proposed dual-band antenna. The antenna was not tested physically. Therefore, in most cases, both HFSS and FEKO were employed to corroborate the simulation results.Keywords: FEKO, HFSS, dual band, shorted annular ring patch
Procedia PDF Downloads 4028599 Enhanced Calibration Map for a Four-Hole Probe for Measuring High Flow Angles
Authors: Jafar Mortadha, Imran Qureshi
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This research explains and compares the modern techniques used for measuring the flow angles of a flowing fluid with the traditional technique of using multi-hole pressure probes. In particular, the focus of the study is on four-hole probes, which offer great reliability and benefits in several applications where the use of modern measurement techniques is either inconvenient or impractical. Due to modern advancements in manufacturing, small multi-hole pressure probes can be made with high precision, which eliminates the need for calibrating every manufactured probe. This study aims to improve the range of calibration maps for a four-hole probe to allow high flow angles to be measured accurately. The research methodology comprises a literature review of the successful calibration definitions that have been implemented on five-hole probes. These definitions are then adapted and applied on a four-hole probe using a set of raw pressures data. A comparison of the different definitions will be carried out in Matlab and the results will be analyzed to determine the best calibration definition. Taking simplicity of implementation into account as well as the reliability of flow angles estimation, an adapted technique from a research paper written in 2002 offered the most promising outcome. Consequently, the method is seen as a good enhancement for four-hole probes and it can substitute for the existing calibration definitions that offer less accuracy.Keywords: calibration definitions, calibration maps, flow measurement techniques, four-hole probes, multi-hole pressure probes
Procedia PDF Downloads 2978598 Characterization of Onboard Reliable Error Correction Code FORSDRAM Controller
Authors: N. Pitcheswara Rao
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In the process of conveying the information there may be a chance of signal being corrupted which leads to the erroneous bits in the message. The message may consist of single, double and multiple bit errors. In high-reliability applications, memory can sustain multiple soft errors due to single or multiple event upsets caused by environmental factors. The traditional hamming code with SEC-DED capability cannot be address these types of errors. It is possible to use powerful non-binary BCH code such as Reed-Solomon code to address multiple errors. However, it could take at least a couple dozen cycles of latency to complete first correction and run at a relatively slow speed. In order to overcome this drawback i.e., to increase speed and latency we are using reed-Muller code.Keywords: SEC-DED, BCH code, Reed-Solomon code, Reed-Muller code
Procedia PDF Downloads 4288597 Visibility Measurements Using a Novel Open-Path Optical Extinction Analyzer
Authors: Nabil Saad, David Morgan, Manish Gupta
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Visibility has become a key component of air quality and is regulated in many areas by environmental laws such as the EPA Clean Air Act and Regional Haze Rule. Typically, visibility is calculated by estimating the optical absorption and scattering of both gases and aerosols. A major component of the aerosols’ climatic effect is due to their scattering and absorption of solar radiation, which are governed by their optical and physical properties. However, the accurate assessment of this effect on global warming, climate change, and air quality is made difficult due to uncertainties in the calculation of single scattering albedo (SSA). Experimental complications arise in the determination of the single scattering albedo of an aerosol particle since it requires the simultaneous measurement of both scattering and extinction. In fact, aerosol optical absorption, in particular, is a difficult measurement to perform, and it’s often associated with large uncertainties when using filter methods or difference methods. In this presentation, we demonstrate the use of a new open-path Optical Extinction Analyzer (OEA) in conjunction with a nephelometer and two particle sizers, emphasizing the benefits that co-employment of the OEA offers to derive the complex refractive index of aerosols and their single scattering albedo parameter. Various use cases, data reproducibility, and instrument calibration will also be presented to highlight the value proposition of this novel Open-Path OEA.Keywords: aerosols, extinction, visibility, albedo
Procedia PDF Downloads 91