Search results for: AIC (Active Interaction Control Device)
12067 Design of Rigid L-Shaped Retaining Walls
Authors: Ahmed Rouili
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Cantilever L-shaped walls are known to be relatively economical as retaining solution. The design starts by proportioning the wall dimensions for which the stability is checked for. A ratio between the lengths of the base and the stem, falling between 0,5 to 0,7, ensure the stability requirements in most cases. However, the displacement pattern of the wall in terms of rotations and translations, and the lateral pressure profile, do not have the same figure for all wall’s proportioning, as it is usually assumed. In the present work, the results of a numerical analysis are presented, different wall geometries were considered. The results show that the proportioning governs the equilibrium between the instantaneous rotation and the translation of the wall-toe, also, the lateral pressure estimation based on the average value between the at-rest and the active pressure, recommended by most design standards, is found to be not applicable for all walls.Keywords: cantilever wall, proportioning, numerical analysis, lateral pressure estimation
Procedia PDF Downloads 32312066 Family Planning Use among Women Living with HIV in Malawi: Analysis from Malawi DHS-2010 Data
Authors: Dereje Habte, Jane Namasasu
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Background: The aim of the analysis was to assess the practice of family planning (FP) among HIV-infected women and the influence of women’s awareness of HIV-positive status in the practice of FP. Methods: The analysis was made among 489 non-pregnant, sexually active, fecund women living with HIV. Result: Of the 489 confirmed HIV positive women, 184 (37.6%) reported that they knew they are HIV positive. The number of women with current use and unmet need of any family planning method were found to be 251 (51.2%) and 107 (21.9%) respectively. Women’s knowledge of HIV-positive status (AOR: 2.32(1.54,3.50)), secondary and above education (AOR: 2.36(1.16,4.78)), presence of 3-4 (AOR: 2.60(1.08,6.28)) and more than four alive children (AOR: 3.03(1.18,7.82)) were significantly associated with current use of family planning. Conclusion: Women’s awareness of HIV-positive status was found to significantly predict family planning practice among women living with HIV.Keywords: family planning, HIV, Malawi, women
Procedia PDF Downloads 60112065 Peaceful Coexistence with Non-Muslims from the Perspective of Quran
Authors: Mohsen Nouraei
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Peaceful coexistence with other religions is one of the most important matters raised the issue of religious diversity. Some people believe that the Quranic policy about the non-Muslims is based on the war and regard the reason of the progress of Islam in the early centuries as based on sword force. This article, which is written in a descriptive and analytical method, investigates this claim and evaluates it with the teachings and instructions of the Quran. The result of this paper shows that not only the teachings of the Quran do not cause the problems, but also The Quranic verses has obligated the Muslims to interact peacefully with their doctrinal opponents and exercise justice in this regard. This paper shows that the principle of interaction with non-Muslims is based on peace and coexistence, and Islam is the inspirer of religious coexistence with the followers of other religions.Keywords: Quran, peace, religious coexistence, Christians, Jewish
Procedia PDF Downloads 41812064 Stress Study in Implants Dental
Authors: M. Benlebna, B. Serier, B. Bachir Bouiadjra, S. Khalkhal
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This study focuses on the mechanical behavior of a dental prosthesis subjected to dynamic loads chewing. It covers a three-dimensional analysis by the finite element method, the level of distribution of equivalent stresses induced in the bone between the implants (depending on the number of implants). The studied structure, consisting of a braced, implant and mandibular bone is subjected to dynamic loading of variable amplitude in three directions corrono-apical, mesial-distal and bucco-lingual. These efforts simulate those of mastication. We show that compared to the implantation of a single implant, implantology using two implants promotes the weakening of the bones. This weakness is all the more likely that the implants are located in close proximity to one another.Keywords: stress, bone, dental implant, distribution, stress levels, dynamic, effort, interaction, prosthesis
Procedia PDF Downloads 40412063 Ultrasound Assisted Extraction and Microwave Assisted Extraction of Carotenoids from Melon Shells
Authors: A. Brinda Lakshmi, J. Lakshmi Priya
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Cantaloupes (muskmelon and watermelon) contain biologically active molecules such as carotenoids which are natural pigments used as food colorants and afford health benefits. ß-carotene is the major source of carotenoids present in muskmelon and watermelon shell. Carotenoids were extracted using Microwave assisted extraction (MAE) and Ultrasound assisted extraction (UAE) utilising organic lipophilic solvents such as acetone, methanol, and hexane. Extraction conditions feed-solvent ratio, microwave power, ultrasound frequency, temperature and particle size were varied and optimized. It was found that the yield of carotenoids was higher using UAE than MAE, and muskmelon had the highest yield of carotenoids when was ethanol used as a solvent for 0.5 mm particle size.Keywords: carotenoids, extraction, muskmelon shell, watermelon shell
Procedia PDF Downloads 27012062 Efficacy of Plant Extracts on Insect Pests of Watermelon and Their Effects on Nutritional Contents of the Fruits
Authors: Fatai Olaitan Alao, Thimoty Abiodun Adebayo, Oladele Abiodun Olaniran
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This experiment was conducted at Ladoke Akintola University of Technology, Ogbomoso, Teaching and Research farm during the major and minor planting season , 2017 to determine the effects of Annona squamosa (Linn.) and Moringa oleifera (Lam) extracts on insect pests of watermelon and their effects on nutritional contents of watermelon fruits. Synthetic insecticide and untreated plots were included in the treatments for comparison. Selected plants were prepared with cold water and each plant extracts was applied at three different concentrations (5,10 and 20% v/v). Data were collected on population density of insect pests, number of aborted fruits, number of defoliated flowers , the yield was calculated in t/ha, nutritional and fatty acid contents were determine using gas chromatography. The results show that the two major insects were observed - Diabrotica undicimpunctata and Dacus cucurbitea. The tested plant extracts had about 65% control of the observed insect pests when compared with the control and the two plant extracts had the same insecticidal efficacy. However, the applied plant extracts at 20% v/v had higher insecticidal effects than the other tested concentrations. Significant higher yield was observed on the plant extracts treated plants compared with untreated plants which had the least yield() but none of the plant extracts performed effectively as Lambdachyalothrin in the control of insect pests and yield. Meanwhile, the tested plant extracts significantly improved the proximate and fatty acid contents of watermelon fruits while Lambdachyalothrin contributed negatively to the nutritional contents of watermelon fruits. Therefore, A. squpmosa and M. oleifera can be used in the management of insect pests and to improve the nutritional contents of the watermelon especially in the organic farming system.Keywords: Annona squamosa, Dacus cucubitea, Diabrotical undicimpunctata, Moringa oleifera, watermelon
Procedia PDF Downloads 12512061 Navigating the VUCA World with a Strong Heart and Mind: How to Build Passion and Character
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The paper presents the PASSION Programme designed by a government school in Singapore, guided by national goals as well as research-based pedagogies that aims to nurture students to become lifelong learners with the strength of character. The design and enactment of the integrated approach to develop in students good character, resilience and social-emotional well-being, future readiness, and active citizenship is guided by a set of principles that amalgamates Biesta’s domains of purposes of education and authentic learning. Data in terms of evidence of students’ learning and students’ feedback were collected, analysed, and suggests that the learning experience benefitted students by boosting their self-confidence, self-directed and collaborative learning skills, as well as empathy.Keywords: lifelong learning, character and citizenship education, education and career guidance, 21CC, teaching and learning empathy
Procedia PDF Downloads 14612060 Electrodeposition of Silicon Nanoparticles Using Ionic Liquid for Energy Storage Application
Authors: Anjali Vanpariya, Priyanka Marathey, Sakshum Khanna, Roma Patel, Indrajit Mukhopadhyay
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Silicon (Si) is a promising negative electrode material for lithium-ion batteries (LiBs) due to its low cost, non-toxicity, and a high theoretical capacity of 4200 mAhg⁻¹. The primary challenge of the application of Si-based LiBs is large volume expansion (~ 300%) during the charge-discharge process. Incorporation of graphene, carbon nanotubes (CNTs), morphological control, and nanoparticles was utilized as effective strategies to tackle volume expansion issues. However, molten salt methods can resolve the issue, but high-temperature requirement limits its application. For sustainable and practical approach, room temperature (RT) based methods are essentially required. Use of ionic liquids (ILs) for electrodeposition of Si nanostructures can possibly resolve the issue of temperature as well as greener media. In this work, electrodeposition of Si nanoparticles on gold substrate was successfully carried out in the presence of ILs media, 1-butyl-3-methylimidazolium-bis (trifluoromethyl sulfonyl) imide (BMImTf₂N) at room temperature. Cyclic voltammetry (CV) suggests the sequential reduction of Si⁴⁺ to Si²⁺ and then Si nanoparticles (SiNs). The structure and morphology of the electrodeposited SiNs were investigated by FE-SEM and observed interconnected Si nanoparticles of average particle size ⁓100-200 nm. XRD and XPS data confirm the deposition of Si on Au (111). The first discharge-charge capacity of Si anode material has been found to be 1857 and 422 mAhg⁻¹, respectively, at current density 7.8 Ag⁻¹. The irreversible capacity of the first discharge-charge process can be attributed to the solid electrolyte interface (SEI) formation via electrolyte decomposition, and trapped Li⁺ inserted into the inner pores of Si. Pulverization of SiNs results in the creation of a new active site, which facilitates the formation of new SEI in the subsequent cycles leading to fading in a specific capacity. After 20 cycles, charge-discharge profiles have been stabilized, and a reversible capacity of 150 mAhg⁻¹ is retained. Electrochemical impedance spectroscopy (EIS) data shows the decrease in Rct value from 94.7 to 47.6 kΩ after 50 cycles of charge-discharge, which demonstrates the improvements of the interfacial charge transfer kinetics. The decrease in the Warburg impedance after 50 cycles of charge-discharge measurements indicates facile diffusion in fragmented and smaller Si nanoparticles. In summary, Si nanoparticles deposited on gold substrate using ILs as media and characterized well with different analytical techniques. Synthesized material was successfully utilized for LiBs application, which is well supported by CV and EIS data.Keywords: silicon nanoparticles, ionic liquid, electrodeposition, cyclic voltammetry, Li-ion battery
Procedia PDF Downloads 12512059 Exploring the Governmentality of Practice in Communication Education in Ghana
Authors: Wincharles Coker
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This study troubles the role the state as the chief sponsor of higher education plays in shaping communication training in Ghana. Using a public university as a case study, it explores how the government of Ghana, through its regimes of control, exercises its authority over the means of production in the academy. Based on Wenger’s community of practice theory and critical theory, the research analyzes the political economy within which higher education in the country operates, focusing on the mandates of two of its bodies: the National Council for Tertiary Education (NCTE) and the National Accreditation Board (NAB). Results show that communication training in Ghana is shaped by three basic strategies of control: developmentalism, bureaucratization, and corporatization. This governmentality, the research reveals nonetheless, largely constrains the agency and practices of the community of communication faculty and administrators, and thus presents a major challenge to the exercise of intellectual freedom, and the self-critical nature of the academy. The study bears implications for further research in the political economy of communication studies, the administration of higher education, and critical/cultural studies in education.Keywords: communication, developmentalism, educattion, governmentality
Procedia PDF Downloads 35912058 Performance Evaluation of Discrete Fourier Transform Algorithm Based PMU for Wide Area Measurement System
Authors: Alpesh Adeshara, Rajendrasinh Jadeja, Praghnesh Bhatt
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Implementation of advanced technologies requires sophisticated instruments that deal with the operation, control, restoration and protection of rapidly growing power system network under normal and abnormal conditions. Presently, the applications of Phasor Measurement Unit (PMU) are widely found in real time operation, monitoring, controlling and analysis of power system network as it eliminates the various limitations of Supervisory Control and Data Acquisition System (SCADA) conventionally used in power system. The use of PMU data is very rapidly increasing its importance for online and offline analysis. Wide Area Measurement System (WAMS) is developed as new technology by use of multiple PMUs in power system. The present paper proposes a model of MATLAB based PMU using Discrete Fourier Transform (DFT) algorithm and evaluation of its operation under different contingencies. In this paper, PMU based two bus system having WAMS network is presented as a case study.Keywords: GPS global positioning system, PMU phasor measurement system, WAMS wide area monitoring system, DFT, PDC
Procedia PDF Downloads 49612057 Structural Analysis of Archaeoseismic Records Linked to the 5 July 408 - 410 AD Utica Strong Earthquake (NE Tunisia)
Authors: Noureddine Ben Ayed, Abdelkader Soumaya, Saïd Maouche, Ali Kadri, Mongi Gueddiche, Hayet Khayati-Ammar, Ahmed Braham
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The archaeological monument of Utica, located in north-eastern Tunisia, was founded (8th century BC) By the Phoenicians as a port installed on the trade route connecting Phoenicia and the Straits of Gibraltar in the Mediterranean Sea. The flourishment of this city as an important settlement during the Roman period was followed by a sudden abandonment, disuse and progressive oblivion in the first half of the fifth century AD. This decadence can be attributed to the destructive earthquake of 5 July 408 - 410 AD, affecting this historic city as documented in 1906 by the seismologist Fernand De Montessus De Ballore. The magnitude of the Utica earthquake was estimated at 6.8 by the Tunisian National Institute of Meteorology (INM). In order to highlight the damage caused by this earthquake, a field survey was carried out at the Utica ruins to detect and analyse the earthquake archaeological effects (EAEs) using structural geology methods. This approach allowed us to highlight several structural damages, including: (1) folded mortar pavements, (2) cracks affecting the mosaic and walls of a water basin in the "House of the Grand Oecus", (3) displaced columns, (4) block extrusion in masonry walls, (5) undulations in mosaic pavements, (6) tilted walls. The structural analysis of these EAEs and data measurements reveal a seismic cause for all evidence of deformation in the Utica monument. The maximum horizontal strain of the ground (e.g. SHmax) inferred from the building oriented damage in Utica shows a NNW-SSE direction under a compressive tectonic regime. For the seismogenic source of this earthquake, we propose the active E-W to NE-SW trending Utique - Ghar El Melh reverse fault, passing through the Utica Monument and extending towards the Ghar El Melh Lake, as the causative tectonic structure. The active fault trace is well supported by instrumental seismicity, geophysical data (e.g., gravity, seismic profiles) and geomorphological analyses. In summary, we find that the archaeoseismic records detected at Utica are similar to those observed at many other archaeological sites affected by destructive ancient earthquakes around the world. Furthermore, the calculated orientation of the average maximum horizontal stress (SHmax) closely match the state of the actual stress field, as highlighted by some earthquake focal mechanisms in this region.Keywords: Tunisia, utica, seimogenic fault, archaeological earthquake effects
Procedia PDF Downloads 4512056 Structure Elucidation of Isolated Active Compounds from Nigella sativa and Calotropis procera and Their Efficacy for Treatment of Asthma
Authors: Intisar S. A. Elzein
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In Saudi Arabia parts of Nigella sativa, and Calotropis procera are commonly used in folk medicine for the treatment of asthma, bronchitis, cough, eczema and other diseases. The purpose of the study is to identify chemical constituents of Nigella sativa seed and Calotropis procera leave isolated by the bioassay guided fractionation process and find out their relevance to the alleged efficacy of the plant in treating asthma. The medicinal properties of both plants for asthma treatment referred to the rich abundance of thymoquinone and phytol compounds isolated from the essential oil of their seed and leave extracts, which they can form a part of molecules of vitamin K.Keywords: asthma, Calotropis procera, chemical constituents, Nigella sativa, vitamin K
Procedia PDF Downloads 25112055 Degradation of Poly -β- Hydroxybutyrate by Trichoderma asperellum
Authors: Nuha Mansour Alhazmi
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Replacement of petro-based plastics by a biodegradable plastic are vastly growing process. Poly-β-hydroxybutyrate (PHB) is a biodegradable biopolymer, synthesized by some bacterial genera. The objective of the current study is to explore the ability of some fungi to biodegrade PHB. The degradation of (PHB) was detected in Petri dish by the formation of a clear zone around the fungal colonies due to the production of depolymerase enzyme which has an interesting role in the PHB degradation process. Among 10 tested fungi, the most active PHB biodegraded fungi were identified as Trichoderma asperellum using morphological and molecular characters. The highest PHB degradation was at 25°C, pH 7.5 after 7 days of incubation for the tested fungi. Finally, the depolymerase enzyme was isolated, purified using column chromatography and characterized. In conclusion, PHB can be biodegraded in solid and liquid medium using depolymerase enzyme from T. asperellum.Keywords: degradation, depolymerase enzyme, PHB, Trichoderma asperellum
Procedia PDF Downloads 18112054 Optimized Electron Diffraction Detection and Data Acquisition in Diffraction Tomography: A Complete Solution by Gatan
Authors: Saleh Gorji, Sahil Gulati, Ana Pakzad
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Continuous electron diffraction tomography, also known as microcrystal electron diffraction (MicroED) or three-dimensional electron diffraction (3DED), is a powerful technique, which in combination with cryo-electron microscopy (cryo-ED), can provide atomic-scale 3D information about the crystal structure and composition of different classes of crystalline materials such as proteins, peptides, and small molecules. Unlike the well-established X-ray crystallography method, 3DED does not require large single crystals and can collect accurate electron diffraction data from crystals as small as 50 – 100 nm. This is a critical advantage as growing larger crystals, as required by X-ray crystallography methods, is often very difficult, time-consuming, and expensive. In most cases, specimens studied via 3DED method are electron beam sensitive, which means there is a limitation on the maximum amount of electron dose one can use to collect the required data for a high-resolution structure determination. Therefore, collecting data using a conventional scintillator-based fiber coupled camera brings additional challenges. This is because of the inherent noise introduced during the electron-to-photon conversion in the scintillator and transfer of light via the fibers to the sensor, which results in a poor signal-to-noise ratio and requires a relatively higher and commonly specimen-damaging electron dose rates, especially for protein crystals. As in other cryo-EM techniques, damage to the specimen can be mitigated if a direct detection camera is used which provides a high signal-to-noise ratio at low electron doses. In this work, we have used two classes of such detectors from Gatan, namely the K3® camera (a monolithic active pixel sensor) and Stela™ (that utilizes DECTRIS hybrid-pixel technology), to address this problem. The K3 is an electron counting detector optimized for low-dose applications (like structural biology cryo-EM), and Stela is also a counting electron detector but optimized for diffraction applications with high speed and high dynamic range. Lastly, data collection workflows, including crystal screening, microscope optics setup (for imaging and diffraction), stage height adjustment at each crystal position, and tomogram acquisition, can be one of the other challenges of the 3DED technique. Traditionally this has been all done manually or in a partly automated fashion using open-source software and scripting, requiring long hours on the microscope (extra cost) and extensive user interaction with the system. We have recently introduced Latitude® D in DigitalMicrograph® software, which is compatible with all pre- and post-energy-filter Gatan cameras and enables 3DED data acquisition in an automated and optimized fashion. Higher quality 3DED data enables structure determination with higher confidence, while automated workflows allow these to be completed considerably faster than before. Using multiple examples, this work will demonstrate how to direct detection electron counting cameras enhance 3DED results (3 to better than 1 Angstrom) for protein and small molecule structure determination. We will also show how Latitude D software facilitates collecting such data in an integrated and fully automated user interface.Keywords: continuous electron diffraction tomography, direct detection, diffraction, Latitude D, Digitalmicrograph, proteins, small molecules
Procedia PDF Downloads 10712053 Numerical Study of UV Irradiation Effect on Air Disinfection Systems
Authors: H. Shokouhmand, M. Degheh, B. Sajadi, H. Sobhani
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The induct ultraviolet germicidal irradiation (UVGI) systems are broadly used nowadays and their utilization is widened every day. Even though these systems are not applicable individually, they are very suitable supplements for the traditional filtration systems. The amount of inactivated microorganisms is dependent on the air velocity, lamp power, fluence rate distribution, and also germicidal susceptibility of microorganisms. In this paper, these factors are investigated utilizing an air-microorganism two-phase numerical model. The eulerian-lagrangian method was used to have more detailed information on the history of each particle. The UVGI system was modeled in three steps including: 1) modeling the air flow, 2) modeling the discrete phase of particles, 3) modeling the UV intensity field, and 4) modeling the particle inactivation. The results from modeling different lamp arrangements and powers showed that the system functions better at more homogeneous irradiation distribution. Since increasing the air flow rate of the device results in increasing of particle inactivation rate, the optimal air velocity shall be adjusted in accordance with the microorganism production rate, and the air quality requirement using the curves represented in this paper.Keywords: CFD, microorganism, two-phase flow, ultraviolet germicidal irradiation
Procedia PDF Downloads 32912052 Influence of Surfactant on Supercooling Degree of Aqueous Titania Nanofluids in Energy Storage Systems
Authors: Hoda Aslani, Mohammad Moghiman, Mohammad Aslani
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Considering the demand to reduce global warming potential and importance of solidification in various applications, there is an increasing interest in energy storage systems to find the efficient phase change materials. Therefore, this paper presents an experimental study and comparison on the potential of titania nanofluids with and without surfactant for cooling energy storage systems. A designed cooling generation device based on compression refrigeration cycle is used to explore nanofluids solidification characteristics. In this work, titania nanoparticles of 0.01, 0.02 and 0.04 wt.% are dispersed in deionized water as base fluid. Measurement of phase change parameters of nanofluids illustrates that the addition of polyvinylpyrrolidone (PVP) as surfactant to titania nanofluids advances the onset nucleation time and leads to lower solidification time. Also, the experimental results show that only adding 0.02 wt.% titania nanoparticles, especially in the case of nanofluids with a surfactant, can evidently reduce the supercooling degree by nearly 70%. Hence, it is concluded that there is a great energy saving potential in the energy storage systems using titania nanofluid with PVP.Keywords: cooling energy storage, nanofluid, PVP, solidification, titania
Procedia PDF Downloads 19212051 Structural and Optical Properties of Silver Sulfide/Reduced Graphene Oxide Nanocomposite
Authors: Oyugi Ngure Robert, Kallen Mulilo Nalyanya, Tabitha A. Amollo
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Nanomaterials have attracted significant attention in research because of their exemplary properties, making them suitable for diverse applications. This paper reports the successful synthesis as well as the structural properties of silver sulfide/reduced graphene oxide (Ag_2 S-rGO) nanocomposite. The nanocomposite was synthesized by the chemical reduction method. Scanning electron microscopy (SEM) showed that the reduced graphene oxide (rGO) sheets were intercalated within the Ag_2 S nanoparticles during the chemical reduction process. The SEM images also showed that Ag_2 S had the shape of nanowires. Further, SEM energy dispersive X-ray (SEM EDX) showed that Ag_2 S-rGO is mainly composed of C, Ag, O, and S. X-ray diffraction analysis manifested a high crystallinity for the nanowire-shaped Ag2S nanoparticles with a d-spacing ranging between 1.0 Å and 5.2 Å. Thermal gravimetric analysis (TGA) showed that rGO enhances the thermal stability of the nanocomposite. Ag_2 S-rGO nanocomposite exhibited strong optical absorption in the UV region. The formed nanocomposite is dispersible in polar and non-polar solvents, qualifying it for solution-based device processing.Keywords: silver sulfide, reduced graphene oxide, nanocomposite, structural properties, optical properties
Procedia PDF Downloads 10012050 Fabrication of LiNbO₃ Based Conspicuous Nanomaterials for Renewable Energy Devices
Authors: Riffat Kalsoom, Qurat-Ul-Ain Javed
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Optical and dielectric properties of lithium niobates have made them the fascinating materials to be used in optical industry for device formation such as Q and optical switching. Synthesis of lithium niobates was carried out by solvothermal process with and without temperature fluctuation at 200°C for 4 hrs, and behavior of properties for different durations was also examined. Prepared samples of LiNbO₃ were examined in a way as crystallographic phases by using XRD diffractometer, morphology by scanning electron microscope (SEM), absorption by UV-Visible Spectroscopy and dielectric measurement by impedance analyzer. A structural change from trigonal to spherical shape was observed by changing the time of reaction. Crystallite size decreases by the temperature fluctuation and increasing reaction time. Band gap decreases whereas dielectric constant and dielectric loss was increased with increasing time of reaction. Trend of AC conductivity is explained by Joschner’s power law. Due to these significant properties, it finds its applications in devices, such as cells, Q switching and optical switching for laser and gigahertz frequencies, respectively and these applications depend on the industrial demands.Keywords: lithium niobates, renewable energy devices, controlled structure, temperature fluctuations
Procedia PDF Downloads 13112049 CFD Analysis of Passive Cooling Building by Using Solar Chimney for Mild or Warm Climates
Authors: Naci Kalkan, Ihsan Dagtekin
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This research presents the design and analysis of solar air-conditioning systems particularly solar chimney which is a passive strategy for natural ventilation, and demonstrates the structures of these systems’ using Computational Fluid Dynamic (CFD) and finally compares the results with several examples, which have been studied experimentally and carried out previously. In order to improve the performance of solar chimney system, highly efficient sub-system components are considered for the design. The general purpose of the research is to understand how efficiently solar chimney systems generate cooling, and is to improve the efficient of such systems for integration with existing and future domestic buildings.Keywords: active and passive solar technologies, solar cooling system, solar chimney, natural ventilation, cavity depth, CFD models for solar chimney
Procedia PDF Downloads 57512048 Metallacyclodimeric Array Containing Both Suprachannels and Cages: Selective Reservoir and Recognition of Diiodomethane
Authors: Daseul Lee, Jeong Jun Lee, Ok-Sang Jung
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Self-assembly of a series of ZnX2 (X- = Cl-, Br-, and I-) with 2,3-bis(4’-nicotinamidephenoxy)naphthalene (L) as a new bidentate pyridyl-donor ligand yields systematic metallacyclodimeric unit, [ZnX2L]2. The supramolecule constitutes a characteristically stacked forming both 1D suprachannels and cages. Weak C-H⋯π and inter-digitated π⋯π interactions are main driving forces in the formation of both suprachannels and cages. The slightly different features between the suprachannel and cage have been investigated by 1H NMR and TG analysis, which solvent quantitatively exchange within only suprachannels. Photo-unstable CH2I2 molecules are stabilized via capturing within suprachannels, which is monitored by UV-Vis spectroscopy. Furthermore, the photoluminescence intensity, from the chromophore naphthyl moiety of [ZnCl2L]2, gradually decreases with the addition of CH2I2. And washing off the CH2I2 by dichloromethane returned the PL intensity back to its approximately original signal.Keywords: metallacyclodimer, suprachannel, π⋯π interaction, molecular recognition
Procedia PDF Downloads 32212047 Retrofitting of Asymmetric Steel Structure Equipped with Tuned Liquid Column Dampers by Nonlinear Finite Element Modeling
Authors: A. Akbarpour, M. R. Adib Ramezani, M. Zhian, N. Ghorbani Amirabad
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One way to improve the performance of structures against of earthquake is passive control which requires no external power source. In this research, tuned liquid column dampers which are among of systems with the capability to transfer energy between various modes of vibration, are used. For the first time, a liquid column damper for vibration control structure is presented. After modeling this structure in design building software and performing the static and dynamic analysis and obtaining the necessary parameters for the design of tuned liquid column damper, the whole structure will be analyzed in finite elements software. The tuned liquid column dampers are installed on the structure and nonlinear time-history analysis is done in two cases of structures; with and without dampers. Finally the seismic behavior of building in the two cases will be examined. In this study the nonlinear time-history analysis on a twelve-story steel structure equipped with damper subject to records of earthquake including Loma Prieta, Northridge, Imperiall Valley, Pertrolia and Landers was performed. The results of comparing between two cases show that these dampers have reduced lateral displacement and acceleration of levels on average of 10%. Roof displacement and acceleration also reduced respectively 5% and 12%. Due to structural asymmetric in the plan, the maximum displacements of surrounding structures as well as twisting were studied. The results show that the dampers lead to a 10% reduction in the maximum response of structure stories surrounding points. At the same time, placing the dampers, caused to reduce twisting on the floor plan of the structure, Base shear of structure in the different earthquakes also has been reduced on the average of 6%.Keywords: retrofitting, passive control, tuned liquid column damper, finite element analysis
Procedia PDF Downloads 41412046 Rehabilitation Robot in Primary Walking Pattern Training for SCI Patient at Home
Authors: Taisuke Sakaki, Toshihiko Shimokawa, Nobuhiro Ushimi, Koji Murakami, Yong-Kwun Lee, Kazuhiro Tsuruta, Kanta Aoki, Kaoru Fujiie, Ryuji Katamoto, Atsushi Sugyo
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Recently attention has been focused on incomplete spinal cord injuries (SCI) to the central spine caused by pressure on parts of the white matter conduction pathway, such as the pyramidal tract. In this paper, we focus on a training robot designed to assist with primary walking-pattern training. The target patient for this training robot is relearning the basic functions of the usual walking pattern; it is meant especially for those with incomplete-type SCI to the central spine, who are capable of standing by themselves but not of performing walking motions. From the perspective of human engineering, we monitored the operator’s actions to the robot and investigated the movement of joints of the lower extremities, the circumference of the lower extremities, and exercise intensity with the machine. The concept of the device was to provide mild training without any sudden changes in heart rate or blood pressure, which will be particularly useful for the elderly and disabled. The mechanism of the robot is modified to be simple and lightweight with the expectation that it will be used at home.Keywords: training, rehabilitation, SCI patient, welfare, robot
Procedia PDF Downloads 42812045 A Review on Biological Control of Mosquito Vectors
Authors: Asim Abbasi, Muhammad Sufyan, Iqra, Hafiza Javaria Ashraf
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The share of vector-borne diseases (VBDs) in the global burden of infectious diseases is almost 17%. The advent of new drugs and latest research in medical science helped mankind to compete with these lethal diseases but still diseases transmitted by different mosquito species, including filariasis, malaria, viral encephalitis and dengue are serious threats for people living in disease endemic areas. Injudicious and repeated use of pesticides posed selection pressure on mosquitoes leading to development of resistance. Hence biological control agents are under serious consideration of scientific community to be used in vector control programmes. Fish have a history of predating immature stages of different aquatic insects including mosquitoes. The noteworthy examples in Africa and Asia includes, Aphanius discolour and a fish in the Panchax group. Moreover, common mosquito fish, Gambusia affinis predates mostly on temporary water mosquitoes like anopheline as compared to permanent water breeders like culicines. Mosquitoes belonging to genus Toxorhynchites have a worldwide distribution and are mostly associated with the predation of other mosquito larvae habituating with them in natural and artificial water containers. These species are harmless to humans as their adults do not suck human blood but feeds on floral nectar. However, their activity is mostly temperature dependent as Toxorhynchites brevipalpis consume 359 Aedes aegypti larvae at 30-32 ºC in contrast to 154 larvae at 20-26 ºC. Although many bacterial species were isolated from mosquito cadavers but those belonging to genus Bacillus are found highly pathogenic against them. The successful species of this genus include Bacillus thuringiensis and Bacillus sphaericus. The prime targets of B. thuringiensis are mostly the immatures of genus Aedes, Culex, Anopheles and Psorophora while B. sphaericus is specifically toxic against species of Culex, Psorophora and Culiseta. The entomopathogenic nematodes belonging to family, mermithidae are also pathogenic to different mosquito species. Eighty different species of mosquitoes including Anopheles, Aedes and Culex proved to be highly vulnerable to the attack of two mermithid species, Romanomermis culicivorax and R. iyengari. Cytoplasmic polyhedrosis virus was the first described pathogenic virus, isolated from the cadavers of mosquito specie, Culex tarsalis. Other viruses which are pathogenic to culicine includes, iridoviruses, cytopolyhedrosis viruses, entomopoxviruses and parvoviruses. Protozoa species belonging to division microsporidia are the common pathogenic protozoans in mosquito populations which kill their host by the chronic effects of parasitism. Moreover, due to their wide prevalence in anopheline mosquitoes and transversal and horizontal transmission from infected to healthy host, microsporidia of the genera Nosema and Amblyospora have received much attention in various mosquito control programmes. Fungal based mycopesticides are used in biological control of insect pests with 47 species reported virulent against different stages of mosquitoes. These include both aquatic fungi i.e. species of Coelomomyces, Lagenidium giganteum and Culicinomyces clavosporus, and the terrestrial fungi Metarhizium anisopliae and Beauveria bassiana. Hence, it was concluded that the integrated use of all these biological control agents can be a healthy contribution in mosquito control programmes and become a dire need of the time to avoid repeated use of pesticides.Keywords: entomopathogenic nematodes, protozoa, Toxorhynchites, vector-borne
Procedia PDF Downloads 26712044 Social Media Use and Exercise Behaviors
Authors: Justin M. Swanson, Anna Nelson, Daniel Handysides, Patti Herring, Christopher Hill
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Not only may social media use have a psychological impact, but increased use may be tied to decreases in physical activity and influencing sedentary behaviors. Social media can be used to share physically active lifestyles and possibly influence others to participate. In contrast, social media use may have adverse effects by decreasing participation in exercise. This study used a qualitative design to examine the relationship between social media use and exercise patterns. Participants were asked questions about their social media habits and how it might impact their physical activity behaviors. Self-reported exercise seemed to increase after viewing others engage in relatable activities or viewing someone that has overcame challenges. To increase the likelihood of engaging in exercise, exercise related posts should be low in difficulty, require few materials, or displayed progress from the individual posting.Keywords: social media, exercise, physical activity, adults
Procedia PDF Downloads 26512043 The Method for Synthesis of Chromium Oxide Nano Particles as Increasing Color Intensity on Industrial Ceramics
Authors: Bagher Aziz Kalantari, Javad Rafiei, Mohamad Reza Talei Bavil Olyai
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Disclosed is a method of preparing a pigmentary chromium oxide nano particles having 50 percent particle size less than about 100nm. According to the disclosed method, a substantially dry solid composition of potassium dichromate and carbon active is heated in CO2 atmosphere to a temperature of about 600ºc for 1hr. Thereafter, the solid Cr2O3 product was washed twice with distilled water. The other aim of this study is to assess both the colouring performance and the potential of nano-pigments in the ceramic tile decoration. The rationable consists in nano-pigment application in several ceramics, including a comparison of colour performance with conventional micro-pigments.Keywords: green chromium oxide, nano particles, colour performances, particle size
Procedia PDF Downloads 33512042 Estimation of Antiurolithiatic Activity of a Biochemical Medicine, Magnesia phosphorica, in Ethylene Glycol-Induced Nephrolithiasis in Wistar Rats by Urine Analysis, Biochemical, Histopathological, and Electron Microscopic Studies
Authors: Priti S. Tidke, Chandragouda R. Patil
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The present study was designed to investigate the effect of Magnesia phosphorica, a biochemical medicine on urine screeing, biochemical, histopathological, and electron microscopic images in ethylene glycol induced nepholithiasis in rats.Male Wistar albino rats were divided into six groups and were orally administered saline once daily (IR-sham and IR-control) or Magnesia phosphorica 100 mg/kg twice daily for 24 days.The effect of various dilutions of biochemical Mag phos3x, 6x, 30x was determined on urine output by comparing the urine volume collected by keeping individual animals in metabolic cages. Calcium oxalate urolithiasis and hyperoxaluria in male Wistar rats was induced by oral administration of 0.75% Ethylene glycol p.o. daily for 24 days. Simultaneous administration of biochemical 3x, 6x, 30xMag phos (100mg/kg p.o. twice a day) along with ethylene glycol significantly decreased calcium oxalate, urea, creatinine, Calcium, Magnesium, Chloride, Phosphorus, Albumin, Alkaline Phosphatase content in urine compared with vehicle-treated control group.After the completion of treatment period animals were sacrificed, kidneys were removed and subjected to microscopic examination for possible stone formation. Histological estimation of kidney treated with biochemical Mag phos (3x, 6x, 30xMag phos 100 mg/kg, p.o.) along with ethylene glycol inhibited the growth of calculi and reduced the number of stones in kidney compared with control group. Biochemical Mag phos of 3x dilution and its crude equivalent also showed potent diuretic and antiurolithiatic activity in ethylene glycol induced urolithiasis. A significant decrease in the weight of stones was observed after treatment in animals which received biochemical Mag phos of 3x dilution and its crude equivalent in comparison with control groups. From this study, it can be proposed that the 3x dilution of biochemical Mag phos exhibits a significant inhibitory effect on crystal growth, with the improvement of kidney function and substantiates claims on the biological activity of twelve tissue remedies which can be proved scientifically through laboratory animal studies.Keywords: Mag phos, Magnesia phosphorica, ciochemic medicine, urolithiasis, kidney stone, ethylene glycol
Procedia PDF Downloads 42812041 Opto-Electronic Properties of Novel Structures: Sila-Fulleranes
Authors: Farah Marsusi, Mohammad Qasemnazhand
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Density-functional theory (DFT) was applied to investigate the geometry and electronic properties H-terminated Si-fullerene (Si-fullerane). Natural bond orbital (NBO) analysis confirms sp3 hybridization nature of Si-Si bonds in Si-fulleranes. Quantum confinement effect (QCE) does not affect band gap (BG) so strongly in the size between 1 to 1.7 nm. In contrast, the geometry and symmetry of the cage have significant influence on BG. In contrast to their carbon analogues, pentagon rings increase the stability of the cages. Functionalized Si-cages are stable and can be chemically very active. The electronic properties are highly sensitive to the surface chemistry via functionalization with different chemical groups. As a result, BGs and chemical activities of these cages can be drastically tuned through the chemistry of the surface.Keywords: density functional theory, sila-fullerens, NBO analysis, opto-electronic properties
Procedia PDF Downloads 29912040 New Concept for Real Time Selective Harmonics Elimination Based on Lagrange Interpolation Polynomials
Authors: B. Makhlouf, O. Bouchhida, M. Nibouche, K. Laidi
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A variety of methods for selective harmonics elimination pulse width modulation have been developed, the most frequently used for real-time implementation based on look-up tables method. To address real-time requirements based in modified carrier signal is proposed in the presented work, with a general formulation to real-time harmonics control/elimination in switched inverters. Firstly, the proposed method has been demonstrated for a single value of the modulation index. However, in reality, this parameter is variable as a consequence of the voltage (amplitude) variability. In this context, a simple interpolation method for calculating the modified sine carrier signal is proposed. The method allows a continuous adjustment in both amplitude and frequency of the fundamental. To assess the performance of the proposed method, software simulations and hardware experiments have been carried out in the case of a single-phase inverter. Obtained results are very satisfactory.Keywords: harmonic elimination, Particle Swarm Optimisation (PSO), polynomial interpolation, pulse width modulation, real-time harmonics control, voltage inverter
Procedia PDF Downloads 50312039 Plasmonic Biosensor for Early Detection of Environmental DNA (eDNA) Combined with Enzyme Amplification
Authors: Monisha Elumalai, Joana Guerreiro, Joana Carvalho, Marta Prado
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DNA biosensors popularity has been increasing over the past few years. Traditional analytical techniques tend to require complex steps and expensive equipment however DNA biosensors have the advantage of getting simple, fast and economic. Additionally, the combination of DNA biosensors with nanomaterials offers the opportunity to improve the selectivity, sensitivity and the overall performance of the devices. DNA biosensors are based on oligonucleotides as sensing elements. These oligonucleotides are highly specific to complementary DNA sequences resulting in the hybridization of the strands. DNA biosensors are not only an advantage in the clinical field but also applicable in numerous research areas such as food analysis or environmental control. Zebra Mussels (ZM), Dreissena polymorpha are invasive species responsible for enormous negative impacts on the environment and ecosystems. Generally, the detection of ZM is made when the observation of adult or macroscopic larvae's is made however at this stage is too late to avoid the harmful effects. Therefore, there is a need to develop an analytical tool for the early detection of ZM. Here, we present a portable plasmonic biosensor for the detection of environmental DNA (eDNA) released to the environment from this invasive species. The plasmonic DNA biosensor combines gold nanoparticles, as transducer elements, due to their great optical properties and high sensitivity. The detection strategy is based on the immobilization of a short base pair DNA sequence on the nanoparticles surface followed by specific hybridization in the presence of a complementary target DNA. The hybridization events are tracked by the optical response provided by the nanospheres and their surrounding environment. The identification of the DNA sequences (synthetic target and probes) to detect Zebra mussel were designed by using Geneious software in order to maximize the specificity. Moreover, to increase the optical response enzyme amplification of DNA might be used. The gold nanospheres were synthesized and characterized by UV-visible spectrophotometry and transmission electron microscopy (TEM). The obtained nanospheres present the maximum localized surface plasmon resonance (LSPR) peak position are found to be around 519 nm and a diameter of 17nm. The DNA probes modified with a sulfur group at one end of the sequence were then loaded on the gold nanospheres at different ionic strengths and DNA probe concentrations. The optimal DNA probe loading will be selected based on the stability of the optical signal followed by the hybridization study. Hybridization process leads to either nanoparticle dispersion or aggregation based on the presence or absence of the target DNA. Finally, this detection system will be integrated into an optical sensing platform. Considering that the developed device will be used in the field, it should fulfill the inexpensive and portability requirements. The sensing devices based on specific DNA detection holds great potential and can be exploited for sensing applications in-loco.Keywords: ZM DNA, DNA probes, nicking enzyme, gold nanoparticles
Procedia PDF Downloads 24512038 Evaluating the Effectiveness of Digital Game-Based Learning on Educational Outcomes of Students with Special Needs in an Inclusive Classroom
Authors: Shafaq Rubab
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The inclusion of special needs students in a classroom is prevailing gradually in developing countries. Digital game-based learning is one the most effective instructional methodology for special needs students. Digital game-based learning facilitates special needs students who actually face challenges and obstacles in their learning processes. This study aimed to evaluate the effectiveness of digital game-based learning on the educational progress of special needs students in developing countries. The quasi-experimental research was conducted by using purposively selected sample size of eight special needs students. Results of both experimental and control group showed that performance of the experimental group students was better than the control group students and there was a significant difference between both groups’ results. This research strongly recommended that digital game-based learning can help special needs students in an inclusive classroom. It also revealed that special needs students can learn efficiently by using pedagogically sound learning games and game-based learning helps a lot for the self-paced fast-track learning system.Keywords: inclusive education, special needs, digital game-based learning, fast-track learning
Procedia PDF Downloads 294