Search results for: fire response performances
2536 Influence of Kneading Conditions on the Textural Properties of Alumina Catalysts Supports for Hydrotreating
Authors: Lucie Speyer, Vincent Lecocq, Séverine Humbert, Antoine Hugon
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Mesoporous alumina is commonly used as a catalyst support for the hydrotreating of heavy petroleum cuts. The process of fabrication usually involves: the synthesis of the boehmite AlOOH precursor, a kneading-extrusion step, and a calcination in order to obtain the final alumina extrudates. Alumina is described as a complex porous medium, generally agglomerates constituted of aggregated nanocrystallites. Its porous texture directly influences the active phase deposition and mass transfer, and the catalytic properties. Then, it is easy to figure out that each step of the fabrication of the supports has a role on the building of their porous network, and has to be well understood to optimize the process. The synthesis of boehmite by precipitation of aluminum salts was extensively studied in the literature and the effect of various parameters, such as temperature or pH, are known to influence the size and shape of the crystallites and the specific surface area of the support. The calcination step, through the topotactic transition from boehmite to alumina, determines the final properties of the support and can tune the surface area, pore volume and pore diameters from those of boehmite. However, the kneading extrusion step has been subject to a very few studies. It generally consists in two steps: an acid, then a basic kneading, where the boehmite powder is introduced in a mixer and successively added with an acid and a base solution to form an extrudable paste. During the acid kneading, the induced positive charges on the hydroxyl surface groups of boehmite create an electrostatic repulsion which tends to separate the aggregates and even, following the conditions, the crystallites. The basic kneading, by reducing the surface charges, leads to a flocculation phenomenon and can control the reforming of the overall structure. The separation and reassembling of the particles constituting the boehmite paste have a quite obvious influence on the textural properties of the material. In this work, we are focused on the influence of the kneading step on the alumina catalysts supports. Starting from an industrial boehmite, extrudates are prepared using various kneading conditions. The samples are studied by nitrogen physisorption in order to analyze the evolution of the textural properties, and by synchrotron small-angle X-ray scattering (SAXS), a more original method which brings information about agglomeration and aggregation of the samples. The coupling of physisorption and SAXS enables a precise description of the samples, as same as an accurate monitoring of their evolution as a function of the kneading conditions. These ones are found to have a strong influence of the pore volume and pore size distribution of the supports. A mechanism of evolution of the texture during the kneading step is proposed and could be attractive in order to optimize the texture of the supports and then, their catalytic performances.Keywords: alumina catalyst support, kneading, nitrogen physisorption, small-angle X-ray scattering
Procedia PDF Downloads 2542535 Web Quest as the Tool for Business Writing Skills Enhancement at Technical University EFL Classes
Authors: Nadezda Kobzeva
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Under the current trend of globalization, economic and technological dynamics information and the means by which it is delivered and renewed becomes out-of-date rapidly. Thus, educational systems as well as higher education are being seriously tested. New strategies’ developing that is supported by Information and Communication Technology is urgently required. The essential educators’ mission is to meet the demands of the future by preparing our young learners with proper knowledge, skills and innovation capabilities necessary to advance our competitiveness globally. In response to the modern society and future demands, the oldest Siberian Tomsk Polytechnic University has wisely proposed several initiatives to promote the integration of Information and Communication Technology (ICT) in education, and increase the competitiveness of graduates by emphasizing inquiry-based learning, higher order thinking and problem solving. This paper gives a brief overview of how Web Quest as ICT device is being used for language teaching and describes its use advantages for teaching English as a Foreign Language (EFL), in particular business writing skills. This study proposes to use Web Quest to promote higher order thinking and ICT integration in the process of engineers training in Tomsk Polytechnic University, Russia.Keywords: web quest, web quest in pedagogy, resume (CVs) and cover letter writing skills, ICT integration
Procedia PDF Downloads 3792534 Facial Design of Combined Photoelectrocehmcial-Fenton Coupling Nanocomposites for Antibiotic Eliminations
Authors: Xinyong Li
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A new coupling system was constructed by combining photo-electrochemical cell with eletro-fenton cell (PEC-EF). The electrode material in this system was derived from MnyFe₁₋yCo Prussian-Blue-Analog (PBA). Mn₀.₄Fe₀.₆Co₀.₆₇-N@C spin-coated on carbon paper behaved as the gas diffusion cathode and Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ spin-coated on fluorine-tin oxide glass (FTO) as anode. The two separated cells could degrade Sulfamethoxazole (SMX) simultaneously and some coupling mechanisms by PEC and EF enhancing the degradation efficiency were investigated. The continuous on-site generation of H₂O₂ at cathode through an oxygen reduction reaction (ORR) was realized over rotating ring-disk electrode (RRDE). The electron transfer number (n) of the ORR with Mn₀.₄Fe₀.₆Co₀.₆₇-N@C was 2.5 in the selected potential and pH range. The photo-electrochemical properties of Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ were systematically studied, which displayed good response towards visible light. The photo-induced electrons at anode can transfer to cathode for further use. Efficient photo-electro-catalytic performance was observed in degrading SMX. Almost 100% SMX removal was achieved in 120 min. This work not only provided a highly effective technique for antibiotic treatment but also revealed the synergic effect between PEC and EF.Keywords: Electro-Fenton, photo-electrochemical, synergic effect, sulfamethoxazole
Procedia PDF Downloads 1422533 Serviceability of Fabric-Formed Concrete Structures
Authors: Yadgar Tayfur, Antony Darby, Tim Ibell, Mark Evernden, John Orr
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Fabric form-work is a technique to cast concrete structures with a great advantage of saving concrete material of up to 40%. This technique is particularly associated with the optimized concrete structures that usually have smaller cross-section dimensions than equivalent prismatic members. However, this can make the structural system produced from these members prone to smaller serviceability safety margins. Therefore, it is very important to understand the serviceability issue of non-prismatic concrete structures. In this paper, an analytical computer-based model to optimize concrete beams and to predict load-deflection behaviour of both prismatic and non-prismatic concrete beams is presented. The model was developed based on the method of sectional analysis and integration of curvatures. Results from the analytical model were compared to load-deflection behaviour of a number of beams with different geometric and material properties from other researchers. The results of the comparison show that the analytical program can accurately predict the load-deflection response of concrete beams with medium reinforcement ratios. However, it over-estimates deflection values for lightly reinforced specimens. Finally, the analytical program acceptably predicted load-deflection behaviour of on-prismatic concrete beams.Keywords: fabric-formed concrete, continuous beams, optimisation, serviceability
Procedia PDF Downloads 3722532 The Effect of Voice Recognition Dictation Software on Writing Quality in Third Grade Students: An Action Research Study
Authors: Timothy J. Grebec
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This study investigated whether using a voice dictation software program (i.e., Google Voice Typing) has an impact on student writing quality. The research took place in a third-grade general education classroom in a suburban school setting. Because the study involved minors, all data was encrypted and deidentified before analysis. The students completed a series of writings prior to the beginning of the intervention to determine their thoughts and skill level with writing. During the intervention phase, the students were introduced to the voice dictation software, given an opportunity to practice using it, and then assigned writing prompts to be completed using the software. The prompts written by nineteen student participants and surveys of student opinions on writing established a baseline for the study. The data showed that using the dictation software resulted in a 34% increase in the response quality (compared to the Pennsylvania State Standardized Assessment [PSSA] writing guidelines). Of particular interest was the increase in students' proficiency in demonstrating mastery of the English language and conventions and elaborating on the content. Although this type of research is relatively no, it has the potential to reshape the strategies educators have at their disposal when instructing students on written language.Keywords: educational technology, accommodations, students with disabilities, writing instruction, 21st century education
Procedia PDF Downloads 752531 Evaluation of Mixing and Oxygen Transfer Performances for a Stirred Bioreactor Containing P. chrysogenum Broths
Authors: A. C. Blaga, A. Cârlescu, M. Turnea, A. I. Galaction, D. Caşcaval
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The performance of an aerobic stirred bioreactor for fungal fermentation was analyzed on the basis of mixing time and oxygen mass transfer coefficient, by quantifying the influence of some specific geometrical and operational parameters of the bioreactor, as well as the rheological behavior of Penicillium chrysogenum broth (free mycelia and mycelia aggregates). The rheological properties of the fungus broth, controlled by the biomass concentration, its growth rate, and morphology strongly affect the performance of the bioreactor. Experimental data showed that for both morphological structures the accumulation of fungus biomass induces a significant increase of broths viscosity and modifies the rheological behavior. For lower P. chrysogenum concentrations (both morphological conformations), the mixing time initially increases with aeration rate, reaches a maximum value and decreases. This variation can be explained by the formation of small bubbles, due to the presence of solid phase which hinders the bubbles coalescence, the rising velocity of bubbles being reduced by the high apparent viscosity of fungus broths. By biomass accumulation, the variation of mixing time with aeration rate is gradually changed, the continuous reduction of mixing time with air input flow increase being obtained for 33.5 g/l d.w. P. chrysogenum. Owing to the superior apparent viscosity, which reduces considerably the relative contribution of mechanical agitation to the broths mixing, these phenomena are more pronounced for P. chrysogenum free mycelia. Due to the increase of broth apparent viscosity, the biomass accumulation induces two significant effects on oxygen transfer rate: the diminution of turbulence and perturbation of bubbles dispersion - coalescence equilibrium. The increase of P. chrysogenum free mycelia concentration leads to the decrease of kla values. Thus, for the considered variation domain of the main parameters taken into account, namely air superficial velocity from 8.36 10-4 to 5.02 10-3 m/s and specific power input from 100 to 500 W/m3, kla was reduced for 3.7 times for biomass concentration increase from 4 to 36.5 g/l d.w. The broth containing P. crysogenum mycelia aggregates exhibits a particular behavior from the point of view of oxygen transfer. Regardless of bioreactor operating conditions, the increase of biomass concentration leads initially to the increase of oxygen mass transfer rate, the phenomenon that can be explained by the interaction of pellets with bubbles. The results are in relation with the increase of apparent viscosity of broths corresponding to the variation of biomass concentration between the mentioned limits. Thus, the apparent viscosity of the suspension of fungus mycelia aggregates increased for 44.2 times and fungus free mycelia for 63.9 times for CX increase from 4 to 36.5 g/l d.w. By means of the experimental data, some mathematical correlations describing the influences of the considered factors on mixing time and kla have been proposed. The proposed correlations can be used in bioreactor performance evaluation, optimization, and scaling-up.Keywords: biomass concentration, mixing time, oxygen mass transfer, P. chrysogenum broth, stirred bioreactor
Procedia PDF Downloads 3402530 An Experimental Investigation into Fluid Forces on Road Vehicles in Unsteady Flows
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In this research, the effect of unsteady flows acting on road vehicles was experimentally investigated, using an advanced and recently introduced wind tunnel. The aims of this study were to extract the characteristics of fluid forces acting on road vehicles under unsteady wind conditions and obtain new information on drag forces in a practical on-road test. We applied pulsating wind as a representative example of the atmospheric fluctuations that vehicles encounter on the road. That is, we considered the case where the vehicles are moving at constant speed in the air, with large wind oscillations. The experimental tests were performed on the Ahmed-type test model, which is a simplified vehicle model. This model was chosen because of its simplicity and the data accumulated under steady wind conditions. The experiments were carried out with a time-averaged Reynolds number of Re = 4.16x10⁵ and a pulsation period of T = 1.5 s, with amplitude of η = 0.235. Unsteady fluid forces of drag and lift were obtained utilizing a multi-component load cell. It was observed that the unsteady aerodynamic forces differ significantly from those under steady wind conditions. They exhibit a phase shift and an enhanced response to the wind oscillations. Furthermore, their behavior depends on the slant angle of the rear shape of the model.Keywords: Ahmed body, automotive aerodynamics, unsteady wind, wind tunnel test
Procedia PDF Downloads 2932529 Defying the Walls of Autocracy: The Role of the Catholic Church in the Resistance against Dictatorships in South Korea and the Philippines during the Early 1960s and Late 1980s
Authors: Marvin R. Tenecio
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The analysis of "religious resistance" has been prevalent in Asian and Philippine studies. Discussions on religious resistance from a variety of perspectives are deemed as crucial turning points in the concept's ongoing development and expansion. By broadening the backdrop of religious protest between the early 1960s and the late 1980s, the researchers contend that a study examining the role carried by the Catholic Church in the upheavals against dictatorships in South Korea and the Philippines would be beneficial to the body of knowledge. This study examines a variety of historical writings about the activities occurring at that time. The researchers also compare and contrast the Catholic Church's contributions to the Korean and Philippine resistance against Park Chung-Hee and Ferdinand Marcos Sr., respectively, during the early 1960s until the late 1980s, using the lens of history from below, particularly the Pasyon and Revolution. The Catholic Church stood out against human rights abuses, promoted social justice, and mobilized the public for political reform in response to the dictatorships in South Korea and the Philippines. Even though the specific circumstances and personalities may have changed, the Church's position in both countries was vital in opposing authoritarian governments and supporting democratic movements.Keywords: resistance, movements, catholic, church, dictatorship
Procedia PDF Downloads 772528 Vibration Control of Hermetic Compressors Using Flexible Multi-Body Dynamics Theory
Authors: Armin Amindari
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Hermetic compressors are used widely for refrigeration, heat pump, and air conditioning applications. With the improvement of energy conservation and environmental protection requirements, inverter compressors that operates at different speeds have become increasingly attractive in the industry. Although speed change capability is more efficient, passing through resonant frequencies may lead to excessive vibrations. In this work, an integrated vibration control approach based on flexible multi-body dynamics theory is used for optimizing the vibration amplitudes of the compressor at different operating speeds. To examine the compressor vibrations, all the forces and moments exerted on the cylinder block were clarified and minimized using balancers attached to the upper and lower ends of the motor rotor and crankshaft. The vibration response of the system was simulated using Motionview™ software. In addition, mass-spring optimization was adopted to shift the resonant frequencies out of the operating speeds. The modal shapes of the system were studied using Optistruct™ solver. Using this approach, the vibrations were reduced up to 56% through dynamic simulations. The results were in high agreement with various experimental test data. In addition, the vibration resonance problem observed at low speeds was solved by shifting the resonant frequencies through optimization studies.Keywords: vibration, MBD, compressor, hermetic
Procedia PDF Downloads 1002527 Blade-Coating Deposition of Semiconducting Polymer Thin Films: Light-To-Heat Converters
Authors: M. Lehtihet, S. Rosado, C. Pradère, J. Leng
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Poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT: PSS), is a polymer mixture well-known for its semiconducting properties and is widely used in the coating industry for its visible transparency and high electronic conductivity (up to 4600 S/cm) as a transparent non-metallic electrode and in organic light-emitting diodes (OLED). It also possesses strong absorption properties in the Near Infra-Red (NIR) range (λ ranging between 900 nm to 2.5 µm). In the present work, we take advantage of this absorption to explore its potential use as a transparent light-to-heat converter. PEDOT: PSS aqueous dispersions are deposited onto a glass substrate using a blade-coating technique in order to produce uniform coatings with controlled thicknesses ranging in ≈ 400 nm to 2 µm. Blade-coating technique allows us good control of the deposit thickness and uniformity by the tuning of several experimental conditions (blade velocity, evaporation rate, temperature, etc…). This liquid coating technique is a well-known, non-expensive technique to realize thin film coatings on various substrates. For coatings on glass substrates destined to solar insulation applications, the ideal coating would be made of a material able to transmit all the visible range while reflecting the NIR range perfectly, but materials possessing similar properties still have unsatisfactory opacity in the visible too (for example, titanium dioxide nanoparticles). NIR absorbing thin films is a more realistic alternative for such an application. Under solar illumination, PEDOT: PSS thin films heat up due to absorption of NIR light and thus act as planar heaters while maintaining good transparency in the visible range. Whereas they screen some NIR radiation, they also generate heat which is then conducted into the substrate that re-emits this energy by thermal emission in every direction. In order to quantify the heating power of these coatings, a sample (coating on glass) is placed in a black enclosure and illuminated with a solar simulator, a lamp emitting a calibrated radiation very similar to the solar spectrum. The temperature of the rear face of the substrate is measured in real-time using thermocouples and a black-painted Peltier sensor measures the total entering flux (sum of transmitted and re-emitted fluxes). The heating power density of the thin films is estimated from a model of the thin film/glass substrate describing the system, and we estimate the Solar Heat Gain Coefficient (SHGC) to quantify the light-to-heat conversion efficiency of such systems. Eventually, the effect of additives such as dimethyl sulfoxide (DMSO) or optical scatterers (particles) on the performances are also studied, as the first one can alter the IR absorption properties of PEDOT: PSS drastically and the second one can increase the apparent optical path of light within the thin film material.Keywords: PEDOT: PSS, blade-coating, heat, thin-film, Solar spectrum
Procedia PDF Downloads 1622526 Importance of Access to Public Information on Modern Slavery for Brazil's Livestock Sector
Authors: Juliana Brandao, Holly Gibbs, Lisa Naughton, Lisa Rausch
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The Brazilian Amazon continues to be plagued by modern day slave labor, specifically within the cattle production industry. In response to this issue, modern day anti-slavery activists have implemented additional regulations designed to combat slave labor associated with cattle. These regulations have been incorporated into existing agreements designed to control deforestation. The goal of these rules is to prevent the trade of beef contaminated with modern slave labor between supplier farms and slaughterhouses. In this study, we identify farms that make use of modern slave labor, and we use cattle transaction data to track the sale of cattle between farms and slaughterhouses. Our analysis reveals that slaughterhouses, which have signed cattle agreements that include requirements to refuse cattle associated with modern slave labor, have avoided buying cattle from suppliers that were on the dirty list. This trend is especially evident when the "dirty lists" that identify modern-day slave labor users are made publicly accessible online. We conclude that the "dirty list" of modern-day slave labor users should be maintained on publicly available websites to allow slaughterhouses, retailers, and consumers to send powerful market signals that discourage the use of modern-day slave labor.Keywords: cattle ranchers, modern slave labor, deforestation, brazilian amazon
Procedia PDF Downloads 1162525 Evaluation of Hybrid Viscoelastic Damper for Passive Energy Dissipation
Authors: S. S. Ghodsi, M. H. Mehrabi, Zainah Ibrahim, Meldi Suhatril
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This research examines the performance of a hybrid passive control device for enhancing the seismic response of steel frame structures. The device design comprises a damper which employs a viscoelastic material to control both shear and axial strain. In the design, energy is dissipated through the shear strain of a two-layer system of viscoelastic pads which are located between steel plates. In addition, viscoelastic blocks have been included on either side of the main shear damper which obtains compressive strains in the viscoelastic blocks. These dampers not only dissipate energy but also increase the stiffness of the steel frame structure, and the degree to which they increase the stiffness may be controlled by the size and shape. In this research, the cyclical behavior of the damper was examined both experimentally and numerically with finite element modeling. Cyclic loading results of the finite element modeling reveal fundamental characteristics of this hybrid viscoelastic damper. The results indicate that incorporating a damper of the design can significantly improve the seismic performance of steel frame structures.Keywords: cyclic loading, energy dissipation, hybrid damper, passive control system, viscoelastic damper
Procedia PDF Downloads 2082524 Improving Seat Comfort by Semi-Active Control of Magnetorheological Damper
Authors: Karel Šebesta, Jiří Žáček, Matuš Salva, Mohammad Housam
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Drivers of agricultural vehicles are exposed to continuous vibration caused by driving over rough terrain. The long-term effects of these vibrations could start with a decreased level of vigilance at work and could reach the level of several health problems. Therefore, eliminating the vibration to maximize the comfort of the driver is essential for better/longer performance. One of the modern damping systems, which can deal with this problem is the Semi-active (S/A) suspension system featuring a Magnetorheological (MR) damper. With this damper, the damping level can be adjusted using varying currents through the coil. Adjustments of the damping force can be carried out continuously based on the evaluated data (position and acceleration of seat) by the control algorithm. The advantage of this system is the wide dynamic range and the high speed of force response time. Compared to other S/A or active systems, the MR damper does not need as much electrical power, and the system is much simpler. This paper aims to prove the effectiveness of this damping system used in the tractor seat. The vibration testing stand was designed and manufactured specifically for this type of research, which is used to simulate vibrations with constant amplitude at variable frequency.Keywords: magnetorheological damper, semi-active suspension, seat scissor mechanism, sky-hook
Procedia PDF Downloads 962523 Validating Texture Analysis as a Tool for Determining Bioplastic (Bio)Degradation
Authors: Sally J. Price, Greg F. Walker, Weiyi Liu, Craig R. Bunt
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Plastics, due to their long lifespan, are becoming more of an environmental concern once their useful life has been completed. There are a vast array of different types of plastic, and they can be found in almost every ecosystem on earth and are of particular concern in terrestrial environments where they can become incorporated into the food chain. Hence bioplastics have become more of interest to manufacturers and the public recently as they have the ability to (bio)degrade in commercial and in home composting situations. However, tools in which to quantify how they degrade in response to environmental variables are still being developed -one such approach is texture analysis using a TA.XT Texture Analyser, Stable Microsystems, was used to determine the force required to break or punch holes in standard ASTM D638 Type IV 3D printed bioplastic “dogbones” depending on the thicknesses of them. Manufacturers’ recommendations for calibrating the Texture Analyser are one such approach for standardising results; however, an independent technique using dummy dogbones and a substitute for the bioplastic was used alongside the samples. This approach was unexpectedly more valuable than realised at the start of the trial as irregular results were later discovered with the substitute material before valuable samples collected from the field were lost due to possible machine malfunction. This work will show the value of having an independent approach to machine calibration for accurate sample analysis with a Texture Analyser when analysing bioplastic samples.Keywords: bioplastic, degradation, environment, texture analyzer
Procedia PDF Downloads 2062522 Electrochemical Detection of Polycyclic Aromatic Hydrocarbons in Urban Air by Exfoliated Graphite Based Electrode
Authors: A. Sacko, H. Nyoni, T. A. M. Msagati, B. Ntsendwana
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Carbon based materials to target environmental pollutants have become increasingly recognized in science. Electrochemical methods using carbon based materials are notable methods for high sensitive detection of organic pollutants in air. It is therefore in this light that exfoliated graphite electrode was fabricated for electrochemical analysis of PAHs in urban atmospheric air. The electrochemical properties of the graphite electrode were studied using CV and EIS in the presence of acetate buffer supporting electrolyte with 2 Mm ferricyanide as a redox probe. The graphite electrode showed enhanced current response which confirms facile kinetics and enhanced sensitivity. However, the peak to peak (DE) separation increased as a function of scan rate. The EIS showed a high charger transfer resistance. The detection phenanthrene on the exfoliated graphite was studied in the presence of acetate buffer solution at PH 3.5 using DPV. The oxidation peak of phenanthrene was observed at 0.4 V. Under optimized conditions (supporting electrolyte, pH, deposition time, etc.). The detection limit observed was at 5x 10⁻⁸ M. Thus the results demonstrate with further optimization and modification lower concentration detection can be achieved.Keywords: electrochemical detection, exfoliated graphite, PAHs (polycyclic aromatic hydrocarbons), urban air
Procedia PDF Downloads 2042521 Contact-Impact Analysis of Continuum Compliant Athletic Systems
Authors: Theddeus Tochukwu Akano, Omotayo Abayomi Fakinlede
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Proper understanding of the behavior of compliant mechanisms use by athletes is important in order to avoid catastrophic failure. Such compliant mechanisms like the flex-run require the knowledge of their dynamic response and deformation behavior under quickly varying loads. The modeling of finite deformations of the compliant athletic system is described by Neo-Hookean model under contact-impact conditions. The dynamic impact-contact governing equations for both the target and impactor are derived based on the updated Lagrangian approach. A method where contactor and target are considered as a united body is applied in the formulation of the principle of virtual work for the bodies. In this paper, methods of continuum mechanics and nonlinear finite element method were deployed to develop a model that could capture the behavior of the compliant athletic system under quickly varying loads. A hybrid system of symbolic algebra (AceGEN) and a compiled back end (AceFEM) were employed, leveraging both ease of use and computational efficiency. The simulated results reveal the effect of the various contact-impact conditions on the deformation behavior of the impacting compliant mechanism.Keywords: eigenvalue problems, finite element method, robin boundary condition, sturm-liouville problem
Procedia PDF Downloads 4732520 Design and Realization of Double-Delay Line Canceller (DDLC) Using Fpga
Authors: A. E. El-Henawey, A. A. El-Kouny, M. M. Abd –El-Halim
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Moving target indication (MTI) which is an anti-clutter technique that limits the display of clutter echoes. It uses the radar received information primarily to display moving targets only. The purpose of MTI is to discriminate moving targets from a background of clutter or slowly-moving chaff particles as shown in this paper. Processing system in these radars is so massive and complex; since it is supposed to perform a great amount of processing in very short time, in most radar applications the response of a single canceler is not acceptable since it does not have a wide notch in the stop-band. A double-delay canceler is an MTI delay-line canceler employing the two-delay-line configuration to improve the performance by widening the clutter-rejection notches, as compared with single-delay cancelers. This canceler is also called a double canceler, dual-delay canceler, or three-pulse canceler. In this paper, a double delay line canceler is chosen for study due to its simplicity in both concept and implementation. Discussing the implementation of a simple digital moving target indicator (DMTI) using FPGA which has distinct advantages compared to other application specific integrated circuit (ASIC) for the purposes of this work. The FPGA provides flexibility and stability which are important factors in the radar application.Keywords: FPGA, MTI, double delay line canceler, Doppler Shift
Procedia PDF Downloads 6442519 Rethinking Nigeria's Foreign Policy in the Age of Global Terrorism
Authors: Shuaibu Umar Abdul
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This paper examines Nigeria’s foreign policy in the age of global terrorism. It worth saying that the threat of ‘terrorism’ is not peculiar to Western and Middle Eastern countries alone, its tentacles are now spreading all over, Africa inclusive. The issue of domestic terrorism in Nigeria has become pervasive since the return of democratic rule in 1999. This development has never been a witness in any form throughout the year of statehood in Nigeria, the issues of banditry, armed robbery, ritual killing, and criminal activities like kidnapping and pipeline vandalization, the breakdown of law and order, poorly managed infrastructural facilities and corruption remain synonymous to Nigeria. These acts of terrorism no doubt have constituted a challenge that necessitates the paradigm shift in Nigeria’s foreign policy. The study employed the conceptual framework of analysis to lead interrogation; secondary sources were used to generate data while descriptive and content analysis were considered for data presentation and interpretation. In view of the interrogation and discussion on the subject matter, the paper revealed that Nigerian government underrated and underestimated the strength of terrorism within and outside her policy hence, it becomes difficult to address. As a response to the findings and conclusion of the study, the paper recommends among others that Nigeria’s foreign policy has to be rethought, reshaped and remodeled in cognizance to the rising global terrorism for peace, growth and development in the country.Keywords: foreign policy, globe, Nigeria, rethinking, terrorism
Procedia PDF Downloads 3592518 Determinaton of Processing Parameters of Decaffeinated Black Tea by Using Pilot-Scale Supercritical CO₂ Extraction
Authors: Saziye Ilgaz, Atilla Polat
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There is a need for development of new processing techniques to ensure safety and quality of final product while minimizing the adverse impact of extraction solvents on environment and residue levels of these solvents in final product, decaffeinated black tea. In this study pilot scale supercritical carbon dioxide (SCCO₂) extraction was used to produce decaffeinated black tea in place of solvent extraction. Pressure (250, 375, 500 bar), extraction time (60, 180, 300 min), temperature (55, 62.5, 70 °C), CO₂ flow rate (1, 2 ,3 LPM) and co-solvent quantity (0, 2.5, 5 %mol) were selected as extraction parameters. The five factors BoxBehnken experimental design with three center points was performed to generate 46 different processing conditions for caffeine removal from black tea samples. As a result of these 46 experiments caffeine content of black tea samples were reduced from 2.16 % to 0 – 1.81 %. The experiments showed that extraction time, pressure, CO₂ flow rate and co-solvent quantity had great impact on decaffeination yield. Response surface methodology (RSM) was used to optimize the parameters of the supercritical carbon dioxide extraction. Optimum extraction parameters obtained of decaffeinated black tea were as follows: extraction temperature of 62,5 °C, extraction pressure of 375 bar, CO₂ flow rate of 3 LPM, extraction time of 176.5 min and co-solvent quantity of 5 %mol.Keywords: supercritical carbon dioxide, decaffeination, black tea, extraction
Procedia PDF Downloads 3642517 Diabetic Striatopathy as an Initial Presentation of Type 2 Diabetes Mellitus in an 80 Year Old Filipina: A Case Report
Authors: Michelangelo Liban, Debbie Liquete
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A case of a 93-year-old Filipina who experienced a sudden onset of left-sided hemichorea hemiballismus after falling from a standing height due to dizziness and then sought consult at the Emergency Room. She was not known to have diabetes mellitus nor experienced any symptoms of diabetes aside from its rare neurological manifestation of hemichorea-hemiballismus prior to this consult. On further workup, her baseline laboratory tests at the Emergency Room Department showed a CBG of 340mg/dL, an HbA1c of 15%, no ketones were detected in her urine but a hyperdensity with a Hounsfeld unit of 38 on CT, and hyperintensity on T1 weighted MRI on her right striatum with an incidental finding of a subdural hematoma measured as a 0.7cm hyperdensity on her right temporoparietal area with no midline shift. She was then treated with Clonazepam 2mg ¼ tab twice a day before bedtime and insulin 70/30 16 units in the morning and eight units in the evening, which provided good glycemic control maintained at 140-180 mg/dL, complete cessation of the left-sided hemichorea hemiballismus was also observed. The subdural hematoma was deemed non-surgical, and she refused admission into our institution; hence observation on an outpatient basis was done. This is a case of a rare neurological manifestation of diabetes mellitus but with good treatment response to anti-chorea medications combined with diabetes medications.Keywords: hemichorea, hemiballismus, striatopathy, diabetes
Procedia PDF Downloads 832516 A Simulation-Optimization Approach to Control Production, Subcontracting and Maintenance Decisions for a Deteriorating Production System
Authors: Héctor Rivera-Gómez, Eva Selene Hernández-Gress, Oscar Montaño-Arango, Jose Ramon Corona-Armenta
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This research studies the joint production, maintenance and subcontracting control policy for an unreliable deteriorating manufacturing system. Production activities are controlled by a derivation of the Hedging Point Policy, and given that the system is subject to deterioration, it reduces progressively its capacity to satisfy product demand. Multiple deterioration effects are considered, reflected mainly in the quality of the parts produced and the reliability of the machine. Subcontracting is available as support to satisfy product demand; also overhaul maintenance can be conducted to reduce the effects of deterioration. The main objective of the research is to determine simultaneously the production, maintenance and subcontracting rate which minimize the total incurred cost. A stochastic dynamic programming model is developed and solved through a simulation-based approach composed of statistical analysis and optimization with the response surface methodology. The obtained results highlight the strong interactions between production, deterioration and quality which justify the development of an integrated model. A numerical example and a sensitivity analysis are presented to validate our results.Keywords: subcontracting, optimal control, deterioration, simulation, production planning
Procedia PDF Downloads 5802515 Exploitation of Variability for Salinity Tolerance in Maize Hybrids (Zea Mays L.) at Early Growth Stage
Authors: Abdul Qayyum, Hafiz Muhammad Saeed, Mamoona Hanif, Etrat Noor, Waqas Malik, Shoaib Liaqat
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Salinity is extremely serious problem that has a drastic effect on maize crop, environment and causes economic losses of country. An advance technique to overcome salinity is to develop salt tolerant geno types which require screening of huge germplasm to start a breeding program. Therefore, present study was undertaken to screen out 25 maize hybrids of different origin for salinity tolerance at seedling stage under three levels of salt stress 250 and 300 mM NaCl including one control. The existence of variation for tolerance to enhanced NaCl salinity levels at seedling stage in maize proved that hybrids had differing ability to grow under saline environment and potential variability within specie. Almost all the twenty five maize hybrids behaved varyingly in response to different salinity levels. However, the maize hybrids H6, H13, H21, H23 and H24 expressed better performance under salt stress in terms of all six characters and proved to be as highly tolerant while H22, H17 H20, H18, H4, H9, and H8 were identified as moderately tolerant. Hybrids H14, H5, H11 and H3 H12, H2, were expressed as most sensitive to salinity suggesting that screening is an effective tool to exploit genetic variation among maize hybrids and salt tolerance in maize can be enhanced through selection and breeding procedure.Keywords: salinity, hybrids, maize, variation
Procedia PDF Downloads 7182514 Ecosystem Response of a Semi-Enclosed Saline Bay to Damming and Sluice-Management: Case of Lake Grevelingen in the Netherlands
Authors: Marijn Tangelder, Ingeborg Mulder, Jeroen Wijsman, John Janssen, Tom Ysebaert
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The delta works in the Southwest Netherlands drastically changed the estuarine nature of this area. The Grevelingen estuary was dammed off and became a lake in 1971. Since 1978 a connection with the North Sea exists to keep the lake saline but management of the sluices varied over time. Our research of several decades of monitoring data shows that water management practices lead to drastic changes in water quality and consequent ecological shifts in benthic fauna, fish, and bird species. Benthic biomass, dominated by molluscs, showed major changes with an important role for invasive species. Fish migration and, therefore, fish stock in the lake changed with recently smaller fish species and lower biomass values, with consequences for fish eating birds. Implications are made towards future management to re-introduce micro-tide in connection with the North Sea to improve water quality and the ecological status of the lake, as well as consequences for the bordering Natura 2000 terrestrial habitats, including rare dune vegetations, are discussed.Keywords: ecosystem study, Grevelingen, Natura 2000, water management, water quality
Procedia PDF Downloads 1282513 Beyond the 'Human Rights and Development' Discourse: A Quest for a Right to Sustainable Development in International Human Rights Law
Authors: Roman Girma Teshome
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The intersection between development and human rights has been the point of scholarly debate for a long time. Consequently, a number of principles, which extend from the right to development to the human rights-based approach to development, have been adopted to understand the dynamics between the two concepts. Despite these attempts, the exact relationship between development and human rights has not been fully discovered yet. However, the inevitable interdependence between the two notions and the idea that development efforts must be undertaken by giving due regard to human rights guarantees has gained momentum in recent years. On the other hand, the emergence of sustainable development as a widely accepted approach in development goals and policies makes this unsettled convergence even more complicated. The place of sustainable development in human rights law discourse and the role of the latter in ensuring the sustainability of development programs call for a systematic study. Hence, this article seeks to explore the relationship between development and human rights, particularly focusing on the place given to sustainable development principles in international human right law. It will further quest whether there is a right to sustainable development recognized therein. Accordingly, the article asserts that the principles of sustainable development are directly or indirectly recognized in various human rights instruments, which provides an affirmative response to the question raised hereinabove. This work, therefore, will make expeditions through international and regional human rights instruments as well as case laws and interpretative guidelines of human rights bodies to prove this hypothesis.Keywords: sustainable development, human rights, the right to development, the human rights-based approach to development, environmental rights, economic development, social sustainability
Procedia PDF Downloads 2232512 The Effect of Mist Cooling on Sexual Behavior and Semen Quality of Sahiwal Bulls
Authors: Khalid Ahmed Elrabie Abdelrasoul
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The present study was carried out on Sahiwal cattle bulls maintained at the Artificial Breeding Complex, NDRI, Karnal, Hayana, India, to assess the effect of cooling using mist cooling and fanning on Sahiwal bulls in the dry hot summer season. Fourteen Sahiwal bulls were divided into two groups of seven each. Sexual behavior and semen quality traits considered were: Reaction time (RT), Dismounting time (DMT), Total time taken in mounts (TTTM), Flehmen response (FR), Erection Score (ES), Protrusion Score (PS), Intensity of thrust (ITS), Temperament Score (TS), Libido Score (LS), Semen volume, Physical appearance, Mass activity, Initial progressive motility, Non-eosinophilic spermatozoa count (NESC) and post thaw motility percent. Data were analyzed by least squares technique. Group-1 was the control, whereas group-2 (treatment group) bulls were exposed to mist cooling and fanning (thrice a day 15 min each) in the dry hot summer season. Group-2 showed significantly (p < 0.01) higher value in DMT (sec), ES, PS, ITS, LS, semen volume (ml), semen color density, mass activity, initial motility, progressive motility and live sperm.Keywords: mist cooling, Sahiwal bulls, semen quality, sexual behavior
Procedia PDF Downloads 3202511 The Effect of Visfatin on Pregnant Mouse Myometrial Contractility in vitro
Authors: Seham Alsaif, Susan Wray
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Obesity is a worldwide disorder influencing women’s health and childbearing. There is a close relation between obesity and pregnancy related complications. Dyslipidemia and adipokine dysregulation are core environmental changes that may mechanistically link these complications with obesity in pregnant women. We have previously found that visfatin has a relaxant effect on mouse, rat and human myometrial contractility. We hypothesised that visfatin inhibits mouse myometrial contractility through the NAD+ pathway. This study was designed to examine the mechanism of action of visfatin on myometrial contractility. To examine the NAD+ pathway, FK866 which is a potent inhibitor of NAD+ biosynthesis was used. Methods: Myometrial strips from term pregnant mice were dissected, superfused with physiological saline and the effects of visfatin (10nM) on oxytocin-induced contractions (0.5nM) alone and after the infusion of FK866 (10uM) were studied. After regular contractions were established, contractility was examined for control (100%) and test response at 37 °C for 10 min each. Results: FK866 was found to inhibit the effect of visfatin on myometrial contractility (the AUC increased from 89±2% of control, P=0.0009 for visfatin alone to 97±4% of control, P>0.05 for visfatin combined with FK866, n=8). In conclusion, NAD+ pathway appears to be involved in the mechanism of action of visfatin on mouse myometrium. This could have a role in making new targets to prevent obesity-related complications.Keywords: myometrium, obesity, oxytocin, pregnancy, visfatin
Procedia PDF Downloads 1772510 The Legality of the Individual Education Plan from the Teachers’ Perspective in Saudi Arabia
Authors: Sohil I. Alqazlan
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Introduction and Objectives: The individual educational plans (IEPs) is the cornerstone in education for students with special education need (SEN). The Saudi government supported the students’ right to have an IEP, and their education is one of the primary goals for the Ministry of Education (MoE). However, this support does not reflect the huge government investment. For example, some SEN students do not have an IEP, and poor communication was found between IEP teams and student's families. As a result, this study investigated perspectives and understandings of the IEP from the views of SEN teachers in the Saudi context. Methods: This study design utilised a qualitative approach, where in-depth semi-structured interviews were used with 8 SEN teachers in Riyadh (the capital city of Saudi Arabia) schools. In terms of analysing the interviews’ findings, the researcher used the thematic analyses approach. Results and Conclusion: The legality and the consideration of the legal document in Saudi Arabia are the main areas wherein study participants were questioned. It was observed that the IEP is not considered a legal document in the region of Saudi Arabia. As interpreted from the response of the SEN teachers, the IEP lacks the required legality with respect to its implementation in Saudi Arabia. All teachers were in agreement that the IEP is not considered to be a legal document in the Kingdom of Saudi Arabia. As a result, they did not use it for all their students with SEN. Such findings might have affected the teaching quality, and school outcomes as all SEN students must be supported individually depending on their needs.Keywords: individual education plan, special education, IEP, teachers
Procedia PDF Downloads 1712509 Cartagena Protocol and Beyond: Issues and Challenges in the Nigeria's Response to Biosafety
Authors: Dalhat Binta Dan - Ali
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The reality of the new world economic order and the ever increasing importance of biotechnology in the global economy have necessitated the ratification of the Cartagena Protocol on Biosafety and the recent promulgation of Biosafety Act in Nigeria 2015. The legal regimes are anchored on the need to create an enabling environment for the flourishing of bio-trade and also to ensure the safety of the environment and human health. This paper critically examines the legal framework on biosafety by taking a cursory look at its philosophical foundation, key issues and milestones. The paper argues that the extant laws, though a giant leap in the establishment of a legal framework on biosafety, it posits that the legal framework raises debate and controversy on the difficulties of risk assessment on biodiversity and human health, other challenges includes lack of sound institutional capacity and the regimes direction of a hybrid approach between environmental conservation and trade issues. The paper recommend the need for the country to do more in the area of stimulating awareness and establishment of a sound institutional capacity to enable the law ensure adequate level of protection in the field of safe transfer, handling, and use of genetically modified organisms (GMOs) in Nigeria.Keywords: Cartagena protocol, biosafety, issues, challenges, biotrade, genetically modified organism (GMOs), environment
Procedia PDF Downloads 3262508 Chipless RFID Capacity Enhancement Using the E-pulse Technique
Authors: Haythem H. Abdullah, Hesham Elkady
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With the fast increase in radio frequency identification (RFID) applications such as medical recording, library management, etc., the limitation of active tags stems from its need to external batteries as well as passive or active chips. The chipless RFID tag reduces the cost to a large extent but at the expense of utilizing the spectrum. The reduction of the cost of chipless RFID is due to the absence of the chip itself. The identification is done by utilizing the spectrum in such a way that the frequency response of the tags consists of some resonance frequencies that represent the bits. The system capacity is decided by the number of resonators within the pre-specified band. It is important to find a solution to enhance the spectrum utilization when using chipless RFID. Target identification is a process that results in a decision that a specific target is present or not. Several target identification schemes are present, but one of the most successful techniques in radar target identification in the oscillatory region is the extinction pulse technique (E-Pulse). The E-Pulse technique is used to identify targets via its characteristics (natural) modes. By introducing an innovative solution for chipless RFID reader and tag designs, the spectrum utilization goes to the optimum case. In this paper, a novel capacity enhancement scheme based on the E-pulse technique is introduced to improve the performance of the chipless RFID system.Keywords: chipless RFID, E-pulse, natural modes, resonators
Procedia PDF Downloads 802507 Stray Light Reduction Methodology by a Sinusoidal Light Modulation and Three-Parameter Sine Curve Fitting Algorithm for a Reflectance Spectrometer
Authors: Hung Chih Hsieh, Cheng Hao Chang, Yun Hsiang Chang, Yu Lin Chang
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In the applications of the spectrometer, the stray light that comes from the environment affects the measurement results a lot. Hence, environment and instrument quality control for the stray reduction is critical for the spectral reflectance measurement. In this paper, a simple and practical method has been developed to correct a spectrometer's response for measurement errors arising from the environment's and instrument's stray light. A sinusoidal modulated light intensity signal was incident on a tested sample, and then the reflected light was collected by the spectrometer. Since a sinusoidal signal modulated the incident light, the reflected light also had a modulated frequency which was the same as the incident signal. Using the three-parameter sine curve fitting algorithm, we can extract the primary reflectance signal from the total measured signal, which contained the primary reflectance signal and the stray light from the environment. The spectra similarity between the extracted spectra by this proposed method with extreme environment stray light is 99.98% similar to the spectra without the environment's stray light. This result shows that we can measure the reflectance spectra without the affection of the environment's stray light.Keywords: spectrometer, stray light, three-parameter sine curve fitting, spectra extraction
Procedia PDF Downloads 248