Search results for: high fibre
20052 Numerical Study of Elastic Performances of Sandwich Beam with Carbon-Fibre Reinforced Skins
Authors: Soukaina Ounss, Hamid Mounir, Abdellatif El Marjani
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Sandwich materials with composite reinforced skins are mostly required in advanced construction applications with a view to ensure resistant structures. Their lightweight, their high flexural stiffness and their optimal thermal insulation make them a suitable solution to obtain efficient structures with performing rigidity and optimal energy safety. In this paper, the mechanical behavior of a sandwich beam with composite skins reinforced by unidirectional carbon fibers is investigated numerically through analyzing the impact of reinforcements specifications on the longitudinal elastic modulus in order to select the adequate sandwich configuration that has an interesting rigidity and an accurate convergence to the analytical approach which is proposed to verify performed numerical simulations. Therefore, concerned study starts by testing flexion performances of skins with various fibers orientations and volume fractions to determine those to use in sandwich beam. For that, the combination of a reinforcement inclination of 30° and a volume ratio of 60% is selected with the one with 60° of fibers orientation and 40% of volume fraction, this last guarantees to chosen skins an important rigidity with an optimal fibers concentration and a great enhance in convergence to analytical results in the sandwich model for the reason of the crucial core role as transverse shear absorber. Thus, a resistant sandwich beam is elaborated from a face-sheet constituted from two layers of previous skins with fibers oriented in 60° and an epoxy core; concerned beam has a longitudinal elastic modulus of 54 Gpa (gigapascal) that equals to the analytical value by a negligible error of 2%.Keywords: fibers orientation, fibers volume ratio, longitudinal elastic modulus, sandwich beam
Procedia PDF Downloads 16820051 High-Quality Flavor of Black Belly Pork under Lightning Corona Discharge Using Tesla Coil for High Voltage Education
Authors: Kyung-Hoon Jang, Jae-Hyo Park, Kwang-Yeop Jang, Dongjin Kim
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The Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla in 1891. It is used to produce high voltage, low current and high frequency alternating current electricity. Tesla experimented with a number of different configurations consisting of two or sometimes three coupled resonant electric circuits. This paper focuses on development and high voltage education to apply a Tesla coil to cuisine for high quality flavor and taste conditioning as well as high voltage education under 50 kV corona discharge. The result revealed that the velocity of roasted black belly pork by Tesla coil is faster than that of conventional methods such as hot grill and steel plate etc. depending on applied voltage level and applied voltage time. Besides, carbohydrate and crude protein increased, whereas natrium and saccharides significantly decreased after lightning surge by Tesla coil. This idea will be useful in high voltage education and high voltage application.Keywords: corona discharge, Tesla coil, high voltage application, high voltage education
Procedia PDF Downloads 32820050 High Arousal and Athletic Performance
Authors: Turki Mohammed Al Mohaid
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High arousal may lead to inhibited athletic performance, or high positive arousal may enhance performance is controversial. To evaluate and review this issue, 31 athletes (all male) were induced into high pre-determined goal arousal and high arousal without pre-determined goal motivational states and tested on a standard grip strength task. Paced breathing was used to change psychological and physiological arousal. It was noted that significant increases in grip strength performance occurred when arousal was high and experienced as delighted, happy, and pleasant excitement in those with no pre-determined goal motivational states. Blood pressure, heart rate, and other indicators of physiological activity were not found to mediate between psychological arousal and performance. In a situation where athletic performance necessitates maximal motor strength over a short period, performance benefits of high arousal may be enhanced by designing a specific motivational state.Keywords: high arousal, athletic, performance, physiological
Procedia PDF Downloads 11620049 Corruption in India: Causes and Remedial Measures
Authors: Ghulam Nabi Naz
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After independence, the popular belief that Gandhian will not indulge in corruption got a setback, post-independence setup paved the way for heavy corruption. The menace which would have dealt with strong legal provisions has become a way of life of Indian society. Corruption is recognized as the single biggest problem facing the country today. It undermines democracy and rule of law, violates human rights, distorts market and corrodes the moral fibre of people. The paper discusses the causes and possible remedial measures of corruption and response of people in Indian society. It emphasizes the factors which provide fertile ground for growth of corruption like, degradation of moral values, absence of a strong anti-corruption law and its effective enforcement, accountability, consistency and a defective system of fighting elections. The paper also highlights the reforms necessary for fighting corruption in India.Keywords: embezzlement, colonial, licence Raj, good governance, misappropriation, Sangh ideologue, Anna movement
Procedia PDF Downloads 29320048 Improving the Feeding Value of Straws with Pleurotus Ostreatus
Authors: S. Hussain, N. Ahmad, S. Alam, M. Bezabhi, W. H. Hendriks, P. Yu, J. W. Cone
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The high content of lignin in cell walls is the major limiting factor in the digestion and utilisation of cereal crop residues by ruminants. The aim of this study was to evaluate the effectiveness of the white rot fungus, Pleurotus ostreatus (P. ostreatus), to degrade lignin and to enhance the rumen degradability of maize stover, rice straw, wheat straw and their mixture in equal proportion on a dry-matter (DM) basis. Four samples of each substrate were incubated aerobically in triplicate with P. ostreatus for 0 (Control), 21, 28 and 35 days under solid-state conditions (temperature, 24 ͦ C; humidity, 70± 5%). The changes in chemical composition, DM and nutrient losses, and rumen fermentation characteristics using in vitro DM digestibility (DMD) and the in vitro gas production (GP) technique were measured. The results showed that incubation with P. ostreatus decreased (P < 0.001) the contents of neutral detergent fibre and lignin with a concomitant increase (P < 0.001) in the contents of ash and crude protein. The losses of nutrients differed (P < 0.001) among the straw types, with rice straw and maize stover showing the largest (P < 0.05) lignin degradation compared to wheat and mixed straws. The DMD and 72-h cumulative GP increased (P < 0.001) consistently with increasing fungal incubation period and for all substrates the highest values of DMD and GP were measured after 35 days of incubation with P. ostreatus. The lignin degradation was strongly associated with hemicellulose degradation (r = 0.71) across the various straws. Results of the present study demonstrated that incubation of low-quality crop residues with P. ostreatus under solid-state conditions upgrades their feeding value by reducing the content of lignin and increasing the content of crude protein and ruminal degradation.Keywords: crop residues, lignin degradation, maize stovers, wheat straws, white rot fungi
Procedia PDF Downloads 6220047 Seismic Strengthening of Reinforced Concrete Beam-Column Joint by Reversible Mixed Technologies of FRP
Authors: Nasser-Eddine Attari
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After the earthquake many structures were classified as slightly damaged and, being uneconomic to replace them, at least in the short term, suitable means of repairs of the beam column joint area are being studied. Furthermore, there exist a large number of buildings that need retrofitting of the joints before the next earthquake. The paper reports the results of the experimental programme, constituted of three beam-column reinforced concrete joints at a scale of one to three (1/3) tested under the effect of a pre-stressing axial load acting over the column. The beams were subjected at their ends to an alternate cyclic loading under displacement control to simulate a seismic action. Strain and cracking fields were monitored with the help a digital recording camera. Following the analysis of the results, a comparison can be made between the performances in terms of ductility, strength, and mode of failure of the different strengthening solution considered.Keywords: fibre reinforced polymers, joints, reinforced concrete, beam columns
Procedia PDF Downloads 44020046 The Simple Two-Step Polydimethylsiloxane (PDMS) Transferring Process for High Aspect Ratio Microstructures
Authors: Shaoxi Wang, Pouya Rezai
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High aspect ratio is the necessary parts of complex microstructures. Some methods available to achieve high aspect ratio requires expensive materials or complex process; others is difficult to research simple high aspect ratio structures. The paper presents a simple and cheap two-step Polydimethylsioxane (PDMS) transferring process to get high aspect ratio single pillars, which only requires covering the PDMS mold with Brij@52 surface solution. The experimental results demonstrate the method efficiency and effective.Keywords: high aspect ratio, microstructure, PDMS, Brij
Procedia PDF Downloads 26420045 On the Fatigue Behavior of a Triphasic Composite
Authors: G. Minak, D. Ghelli, A. Zucchelli
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This paper presents the results of an experimental characterization of a glass fibre-epoxy composite. The behavior of the traditional two-phase composite has been compared with the one of a new three-phase composite where the epoxy matrix was modified by addition of a 3% weight fraction of montmorillonite nano-particles. Two different types of nano-clays, Cloisite® 30B and RXG7000, produced by Southern Clay Products Inc., have been considered. Three-point bending tests, both monotonic and cyclic, were carried out. A strong reduction of the ultimate flexural strength upon nano-modification has been observed in quasi-static tests. Fatigue tests yielded a smaller strength loss. In both quasi-static and fatigue tests a more pronounced tendency to delamination has been noticed in three-phase composites, especially in the case of 30B nano-clay, with respect to the standard two-phase glass fiber composite.Keywords: bending fatigue, epoxy resin, glass fiber, montmorillonite
Procedia PDF Downloads 44620044 Strength Translation from Spun Yarns to Woven Fabrics
Authors: Anindya Ghosh
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Structural parameters, yarn to yarn friction, strength of ring, rotor, air-jet and open-end friction spun yarns and the strength of fabrics made from these yarns are measured. The ratio of fabric strip strength per yarn and corresponding single yarn strength is considered as a measure of quantifying the fabric assistance. Mechanism of yarn failure inside the fabric is different as that of single yarn and the former exhibit more fibre rupture. Fabrics made from weaker yarns have higher ratio of strip strength to single yarn strength than that made from stronger yarns due to larger increase in the percentage of rupture fibres in the former. The fabric assistance also depends to some extent on the degree of gripping of the yarns that is influenced by the yarn to yarn friction, extent of yarn flattening and yarn diameter.Keywords: fabric assistance, fabric strength, yarn diameter, yarn friction, yarn strength
Procedia PDF Downloads 24920043 Assessment of Bridge Performance with Laminated versus Spring Seismic Isolation
Authors: M. Z. Ramli, A. Adnan, Chee Wei Tan
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To gain a better understanding of earthquake forces on reinforced concrete bridge piers with different bearing condition, a series of experiments was conducted on a realistic, 1:4 scale reinforced concrete bridge pier. The normal practices of laminated seismic isolation bearing is compared with the new design spring seismic isolation bearing where invented by Engineering Seismology and Earthquake Engineering Research (e-SEER), Universiti Teknologi Malaysia. The nonlinear behavior of piers is modeled using the fibre beam theory to verify the experimental works. The hysteresis of bridge pier with different bearing condition was illustrated under different Peak Ground Acceleration (PGAs). The average slope of the hysteresis respectively to the global stiffness was also investigated.Keywords: bridge, laminated seismic isolation, spring seismic isolation, Peak Ground Acceleration, stiffness
Procedia PDF Downloads 56020042 Nutritional Evaluation of Seseame Seed Husk as a Source of Fibre in the Diets of Broiler Chickens
Authors: Maidala A., Bizi A. G., Olaoyo T. G., Lawan Amaza B. I., Makinde O. J., Sudik S. D.
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This study was aimed at evaluating the effects of full or partial replacement of wheat offal by dry Sesame Seed Husk (SSH) on the performance of broiler chickens. One-day-old chicks (n = 120) were randomly allotted to five treatments, each replicated four times. A replicate comprised of eight chicks each in a Completely Randomized Design (CRD). SSH was included at 0, 25, 50, 75, and 100%, respectively. Results showed that there were no significant differences in the Daily feed intake (76.03-88.74), Daily weight gain (35.53-37.66), Feed conversion ratio (2.31-3.21) and Carcass characteristics. The feed cost is reduced as you increase the levels of SSH, and the feed cost N/kg gain was highest in the wheat offal diet and lowest at 100% SSH. It can be concluded that higher levels of up to 100% SSH can be incorporated into broiler rations without deleterious effects on the performance of broilers and concomitant reduction in feed cost.Keywords: SSH, broilers, growth performance, economics of production, hematology, serum biochemistry
Procedia PDF Downloads 1020041 Fabrication and Evaluation of Particleboards from Oil Palm Fronds Blend with Empty Fruit Bunch Fibre
Authors: Ghazi Faisal Najmuldeen, Wahida Amat Fadzila
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The aim of this study is to investigate physical and mechanical properties of experimental particleboards manufactured from mixing the oil palm fronds particles with empty fruit bunch fibers. Variables were two blending ratios (100:0 and 70:30), press temperature (160°C and 180°C) and press time (180 and 300 s). Experimental boards with a target density of 750 kg m-3 were manufactured from these two particles and fibers blended with urea formaldehyde resin and compressed into targeted thickness. The effect of these manufacturing conditions on bending strength, internal bonding, water absorption and thickness swelling were determined. From this research, it can be concluded that hybridization of fibers with fronds particles improved some properties of particleboard. Empty fruit bunch fibers and fronds particleboard showed better modulus of rupture and internal bonding than fronds particleboards.Keywords: oil palm fronds, empty fruit bunch, particleboards, chemistry, environment
Procedia PDF Downloads 33320040 Physical and Thermo-Physical Properties of High Strength Concrete Containing Raw Rice Husk after High Temperature Effect
Authors: B. Akturk, N. Yuzer, N. Kabay
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High temperature is one of the most detrimental effects that cause important changes in concrete’s mechanical, physical, and thermo-physical properties. As a result of these changes, especially high strength concrete (HSC), may exhibit damages such as cracks and spallings. To overcome this problem, incorporating polymer fibers such as polypropylene (PP) in concrete is a very well-known method. In this study, using RRH as a sustainable material instead of PP fiber in HSC to prevent spallings and improve physical and thermo-physical properties were investigated. Therefore, seven HSC mixtures with 0.25 water to binder ratio were prepared, incorporating silica fume and blast furnace slag. PP and RRH were used at 0.2-0.5% and 0.5-3% by weight of cement, respectively. All specimens were subjected to high temperatures (20 (control), 300, 600 and 900˚C) with a heating rate of 2.5˚C/min and after cooling, residual physical and thermo-physical properties were determined.Keywords: high temperature, high strength concrete, polypropylene fiber, raw rice husk, thermo-physical properties
Procedia PDF Downloads 27420039 Surface Modified Electrospun Expanded Polystyrene Fibre with Superhydrophobic/Superoleophillic Properties as Potential Oil Membrane
Authors: S. Oluwagbemiga Alayande, E. Olugbenga Dare, Titus A. M. Msagati, A. Kehinde Akinlabi , P. O. Aiyedun
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This paper presents a cheap route procedure for the preparation of a potential oil membrane with superhydrophobic /superoleophillic properties for selective removal of crude oil from water. In these study, expanded polystyrene (EPS) was electrospun to produce beaded fibers in which zeolite was introduced to the polymer matrix in order to impart rough surface to non-beaded fiber. Films of the EPS and EPS/Zeolite solutions were also made for comparative study. The electrospun fibers EPS, EPS/Zeolite and resultant films were characterized using SEM, BET, FTIR and optical contact angle. The fibers exhibited superhydrophic and superoleophillic wetting properties with water and crude oil. The selective removal of crude oil presents new opportunity for the re-use of EPS as adsorbent in petroleum/petrochemical industry.Keywords: expanded polystyrene, superhydrophobic, superoleophillic, oil-membrane
Procedia PDF Downloads 47220038 The Research about Environmental Assessment Index of Brownfield Redevelopment in Taiwan - A Case Study on Formosa Chemicals and Fibre Corporation, Changhua Branch
Authors: Yang, Min-chih, Shih-Jen Feng, Bo-Tsang Li
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The concept of “Brownfield” has been developed for nearly 35 years since it was put forward in 《Comprehensive Environmental Response, Compensation, and Liability Act, CERCLA》of USA in 1980 for solving the problem of soil contamination of those old industrial lands, and later, many countries have put forward relevant policies and researches continuously. But the related concept in Taiwan, a country has developed its industry for 60 years, is still in its infancy. This leads to the slow development of Brownfield related research and policy in Taiwan. When it comes to build the foundation of Brownfield development, we have to depend on the related experience and research of other countries. They are four aspects about Brownfield: 1. Contaminated Land; 2. Derelict Land; 3. Vacant Land; 4. Previously Development Land. This study will focus on and deeply investigate the Vacant land and contaminated land.Keywords: brownfield, industrial land, redevelopment, assessment index
Procedia PDF Downloads 46520037 Effect of Chemical Treatment on Mechanical Properties of KENAF Fiber Reinforced Unsaturated Polyester Composites
Authors: S. S. Abdullahi, H. Musa, A. A. Salisu, A. Ismaila, A. H. Birniwa
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In this study the treated and untreated kenaf fiber reinforced unsaturated polyester conventional composites were prepared. Hand lay-up technique was used with dump-bell shaped mold. The kenaf bast fiber was retted enzymatically, washed, dried and combed with a nylon brush. A portion of the kenaf fiber was mercerized and treated with benzoylchloride prior to composite fabrication. Untreated kenaf fiber was also used to prepare the composites to serve as control. The cured composites were subjected to various mechanical testes, such as hardness test, impact test and tensile strength test. The results obtained indicated an increase in all the parameters tested with the fiber treatment. This is because the lignin, hemi-celluloses, pectin and other impurities were removed during alkaline treatment (i.e mercerization). This shows that, the durability of the natural cellulosic fibers to different composite applications can be achieved via fiber treatments.Keywords: composite, kenaf fibre, reinforce, retted
Procedia PDF Downloads 51320036 Layered Fiberconcrete Element Building Technology and Strength
Authors: Vitalijs Lusis, Videvuds-Arijs Lapsa, Olga Kononova, Andrejs Krasnikovs
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Steel fibres use in a concrete, such way obtaining Steel Fibre Reinforced Concrete (SFRC), is an important technological direction in building industry. Steel fibers are substituting the steel bars in conventional concrete in another situation is possible to combine them in the concrete structures. Traditionally fibers are homogeneously dispersed in a concrete. At the same time in many situations fiber concrete with homogeneously dispersed fibers is not optimal (majority of added fibers are not participating in a load bearing process). It is obvious, that is possible to create constructions with oriented fibers distribution in them, in different ways. Present research is devoted to one of them. Acknowledgment: This work has been supported by the European Social Fund within the project «Support for the implementation of doctoral studies at Riga Technical University» and project No. 2013/0025/1DP/1.1.1.2.0/13/APIA/VIAA/019 “New “Smart” Nanocomposite Materials for Roads, Bridges, Buildings and Transport Vehicle”.Keywords: fiber reinforced concrete, 4-point bending, steel fiber, SFRC
Procedia PDF Downloads 62920035 Design and Analysis of Hybrid Morphing Smart Wing for Unmanned Aerial Vehicles
Authors: Chetan Gupta, Ramesh Gupta
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Unmanned aerial vehicles, of all sizes, are prime targets of the wing morphing concept as their lightweight structures demand high aerodynamic stability while traversing unsteady atmospheric conditions. In this research study, a hybrid morphing technology is developed to aid the trailing edge of the aircraft wing to alter its camber as a monolithic element rather than functioning as conventional appendages like flaps. Kinematic tailoring, actuation techniques involving shape memory alloys (SMA), piezoelectrics – individually fall short of providing a simplistic solution to the conundrum of morphing aircraft wings. On the other hand, the feature of negligible hysteresis while actuating using compliant mechanisms has shown higher levels of applicability and deliverability in morphing wings of even large aircrafts. This research paper delves into designing a wing section model with a periodic, multi-stable compliant structure requiring lower orders of topological optimization. The design is sub-divided into three smaller domains with external hyperelastic connections to achieve deflections ranging from -15° to +15° at the trailing edge of the wing. To facilitate this functioning, a hybrid actuation system by combining the larger bandwidth feature of piezoelectric macro-fibre composites and relatively higher work densities of shape memory alloy wires are used. Finite element analysis is applied to optimize piezoelectric actuation of the internal compliant structure. A coupled fluid-surface interaction analysis is conducted on the wing section during morphing to study the development of the velocity boundary layer at low Reynold’s numbers of airflow.Keywords: compliant mechanism, hybrid morphing, piezoelectrics, shape memory alloys
Procedia PDF Downloads 31120034 Green Synthesis of Silver Nanoparticles Mediated by Plant by-Product Extracts
Authors: Cristian Moisa, Andreea Lupitu, Adriana Csakvari, Dana G. Radu, Leonard Marian Olariu, Georgeta Pop, Dorina Chambre, Lucian Copolovici, Dana Copolovici
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Green synthesis of nanoparticles (NPs) represents a promising, accessible, eco-friendly, and safe process with significant applications in biotechnology, pharmaceutical sciences, and farming. The aim of our study was to obtain silver nanoparticles, using plant wastes extracts resulted in the essential oils extraction process: Thymus vulgaris L., Origanum vulgare L., Lavandula angustifolia L., and in hemp processing for seed and fibre, Cannabis sativa. Firstly, we obtained aqueous extracts of thyme, oregano, lavender, and hemp (two monoicous and one dioicous varieties), all harvested in western part of Romania. Then, we determined the chemical composition of the extracts by liquid-chromatography coupled with diode array and mass spectrometer detectors. The compounds identified in the extracts were in agreement with earlier published data, and the determination of the antioxidant activity of the obtained extracts by DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assays confirmed their antioxidant activity due to their total polyphenolic content evaluated by Folin-Ciocalteu assay. Then, the silver nanoparticles (AgNPs) were successfully biosynthesised, as was demonstrated by UV-VIS, FT-IR spectroscopies, and SEM, by reacting AgNO₃ solution and plant extracts. AgNPs were spherical in shape, with less than 30 nm in diameter, and had a good bactericidal activity against Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas fluorescens).Keywords: plant wastes extracts, chemical composition, high performance liquid chromatography mass spectrometer, HPLC-MS, scanning electron microscopy, SEM, silver nanoparticles
Procedia PDF Downloads 18020033 High-Speed Electrical Drives and Applications: A Review
Authors: Vaishnavi Patil, K. M. Kurundkar
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Electrical Drives play a vital role in industry development and applications. Drives have an inevitable part in the needs of various fields such as industry, commercial, and domestic applications. The development of material technology, Power Electronics devices, and accompanying applications led to the focus of industry and researchers on high-speed electrical drives. Numerous articles charted the applications of electrical machines and various converters for high-speed applications. The choice depends on the application under study. This paper goals to highlight high-speed applications, main challenges, and some applications of electrical drives in the field.Keywords: high-speed, electrical machines, drives, applications
Procedia PDF Downloads 6820032 A Low-Power, Low-Noise and High Linearity 60 GHz LNA for WPAN Applications
Authors: Noha Al Majid, Said Mazer, Moulhime El Bekkali, Catherine Algani, Mahmoud Mehdi
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A low noise figure (NF) and high linearity V-band Low Noise Amplifier (LNA) is reported in this article. The LNA compromises a three-stage cascode configuration. This LNA will be used as a part of a WPAN (Wireless Personal Area Network) receiver in the millimeter-wave band at 60 GHz. It is designed according to the MMIC technology (Monolithic Microwave Integrated Circuit) in PH 15 process from UMS foundry and uses a 0.15 μm GaAs PHEMT (Pseudomorphic High Electron Mobility Transistor). The particularity of this LNA compared to other LNAs in literature is its very low noise figure which is equal to 1 dB and its high linearity (IIP3 is about 22 dB). The LNA consumes 0.24 Watts, achieving a high gain which is about 23 dB, an input return loss better than -10 dB and an output return loss better than -8 dB.Keywords: low noise amplifier, V-band, MMIC technology, LNA, amplifier, cascode, pseudomorphic high electron mobility transistor (PHEMT), high linearity
Procedia PDF Downloads 51420031 An Experimental Study of Dynamic Compressive Strength of Bushveld Complex Brittle Rocks under Impact Loadingsa Chemicals and Fibre Corporation, Changhua Branch
Authors: A. Mudau, T. R. Stacey, R. A. Govender
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This paper reports for the first time the findings on the dynamic compressive strength data of Bushveld Complex brittle rock materials. These rocks were subjected to both quasi-static and impact loading tests to help understand their behaviour both under quasi-static and dynamic loading conditions. Unlike quasi-static tests, characterization of dynamic behaviour of materials is challenging, in particularly brittle rock materials. The split Hopkinson pressure bar (SHPB) results reported for anorthosite and norite showed relatively low values for dynamic compressive strength compared to the quasi-static uniaxial compressive strength data. It was noticed that the dynamic stress conditions were not fully attained during testing, as well as constant strain rate.Keywords: Bushveld Complex, dynamic comperession, rock brittleness, stress equilibrium
Procedia PDF Downloads 49820030 Discrete Crack Modeling of Side Face FRP-Strengthened Concrete Beam
Authors: Shahriar Shahbazpanahi, Mohammad Hemen Jannaty, Alaleh Kamgar
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Shear strengthening can be carried out in concrete structures by external fibre reinforced polymer (FRP). In the present investigation, a new fracture mechanics model is developed to model side face of strengthened concrete beam by external FRP. Discrete crack is simulated by a spring element with softening behavior ahead of the crack tip to model the cohesive zone in concrete. A truss element is used, parallel to the spring element, to simulate the energy dissipation rate by the FRP. The strain energy release rate is calculated directly by using a virtual crack closure technique and then, the crack propagation criterion is presented. The results are found acceptable when compared to previous experimental results and ABAQUS software data. It is observed that the length of the fracture process zone (FPZ) increases with the application of FRP in side face at the same load in comparison with that of the control beam.Keywords: FPZ, fracture, FRP, shear
Procedia PDF Downloads 53420029 Students Perceptions on the Relevance of High School Mathematics in University Education in South Africa
Authors: Gilbert Makanda, Roelf Sypkens
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In this study we investigated the relevance of high school mathematics in university education. The paper particularly focused on whether the concepts taught in high school are enough for engineering courses at diploma level. The study identified particular concepts that are required in engineering courses whether they were adequately covered in high school. A questionnaire was used to investigate whether relevant topics were covered in high school. The respondents were 228 first year students at the Central University of Technology in the Faculty of Engineering and Information Technology. The study indicates that there are some topics such as integration, complex numbers and matrices that are not done at high schools and are required in engineering courses at university. It is further observed that some students did not cover the topics that are in the current syllabus. Female students enter the university less prepared than their male counterparts. More than 30% of the respondents in this study felt that high school mathematics was not useful for them to be able to do engineering courses.Keywords: high school mathematics, university education, SPSS package, students' perceptions
Procedia PDF Downloads 28520028 Mapping New Technologies for Sustainability along the Fashion Supply Chain
Authors: Hilde Heim
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The textile industry is known for its swift adoption of innovations in fashion technology (Fash-Tech). The industry is also known for its harmful effects on the environment. Opportunely, Fash-Tech is expected to facilitate the turn towards more sustainable practice. However, although several technologies have the potential for advancing sustainable practice, many industry players, whether large or small, are confused and misinformed about Fash-Tech adoption, application, and impact. Through a visual poster presentation, this project aims to map global fashion innovations along the supply chain from fibre production to waste management, thus providing a clearer picture of numbers, scale, and adoption. While the project aims to identify Fash-Tech effectiveness in reaching sustainability goals, it also identifies areas of congestion as well as insufficiency in the accessibility of Fash-Tech. This project intends to help inform future decisions in business, investment, and policy for the advancement of sustainable practice.Keywords: fashion technology, sustainability, supply chain, enterprise management
Procedia PDF Downloads 24120027 Evaluation of the Use of U-Wrap Anchorage Systems for Strengthening Concrete Members Reinforced by Fiber Reinforced-Polymer Laminate
Authors: Mai A. Aljaberi
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The anchorage of fibre-reinforced polymer (FRP) sheets is the most effective solution to prevent or delay debonding failure; this system has proven to get better levels of FRP utilization. Unfortunately, the related design information is still unclear. This shortcoming limits the widespread use of the anchorage system. In order to minimize the knowledge gap about the design of U-wrap anchors, this paper reports the results of tested beams which were strengthened with carbon fiber-reinforced polymer (CFRP) sheets at their tension sides and secured with U-wrap anchors at each end of the longitudinal CFRP. The beams were tested under four-point loading until failure. The parameters examined include the compressive strength of the concrete and the number of longitudinal CFRP. It is concluded that these parameters have a considerable effect on the debonding of the strain. The greatest improvement in the strain was 55.8% over the control beam.Keywords: CFRP, concrete strengthening, debonding failure, debonding strain, U-wrap anchor
Procedia PDF Downloads 8320026 Effects of Enzymatic Liquefaction on the Physicochemical Properties and Antioxidant Activity of Zn-Amaranth (Amaranthus viridis) Puree
Authors: M. A. Siti Faridah, K. Muhammad, H. M. Ghazali, Y. A. Yusof
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This study was conducted to investigate the effects of three variables namely types of cell wall degrading enzymes (Viscozyme L, Pectinex Ultra SP-L, Rapidase PAC, Rohament CL and Rohapect PTE) at varying concentrations (0.25-3% v/w) and times (30 min-24 h) on the zinc (Zn-) amaranth purees. Liquefaction treatment of the Zn-amaranth purees with Viscozyme (1% v/w at pH 5 and 45ºC for 3 h) was found to be the best procedure, which produced Zn-amaranth puree with low viscosity (8.60 mPas). Zn-amaranth purees were also found to have the highest metallo-chlorophyll derivative contents (0.16 mg/g), free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) values (12.49 mM (TE)/g fresh weight) and ferric reducing antioxidant power (FRAP) values (4.57 mM (TE)/g fresh weight) within 3 h of liquefaction. Other physicochemical properties of the enzyme-liquefied Zn-amaranth purees indicated that lightness (L*) (12.54), greenness a*/b* (-0.30), reducing sugar (103.88 mg/mL) and soluble dietary fibre (5.94%) of the purees were higher compared to that of nonenzyme-liquefied amaranth purees.Keywords: amaranth, antioxidant, chlorophyll derivative, enzymatic liquefaction
Procedia PDF Downloads 14620025 GE as a Channel Material in P-Type MOSFETs
Authors: S. Slimani, B. Djellouli
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Novel materials and innovative device structures has become necessary for the future of CMOS. High mobility materials like Ge is a very promising material due to its high mobility and is being considered to replace Si in the channel to achieve higher drive currents and switching speeds .Various approaches to circumvent the scaling limits to benchmark the performance of nanoscale MOSFETS with different channel materials, the optimized structure is simulated within nextnano in order to highlight the quantum effects on DG MOSFETs when Si is replaced by Ge and SiO2 is replaced by ZrO2 and HfO2as the gate dielectric. The results have shown that Ge MOSFET have the highest mobility and high permittivity oxides serve to maintain high drive current. The simulations show significant improvements compared with DGMOSFET using SiO2 gate dielectric and Si channel.Keywords: high mobility, high-k, quantum effects, SOI-DGMOSFET
Procedia PDF Downloads 36720024 External Strengthening of RC Continuous Beams Using FRP Plates: Finite Element Model
Authors: Mohammed A. Sakr, Tarek M. Khalifa, Walid N. Mansour
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Fiber reinforced polymer (FRP) installation is a very effective way to repair and strengthen structures that have become structurally weak over their life span. This technique attracted the concerning of researchers during the last two decades. This paper presents a simple uniaxial nonlinear finite element model (UNFEM) able to accurately estimate the load-carrying capacity, different failure modes and the interfacial stresses of reinforced concrete (RC) continuous beams flexurally strengthened with externally bonded FRP plates on the upper and lower fibers. Results of the proposed finite element (FE) model are verified by comparing them with experimental measurements available in the literature. The agreement between numerical and experimental results is very good. Considering fracture energy of adhesive is necessary to get a realistic load carrying capacity of continuous RC beams strengthened with FRP. This simple UNFEM is able to help design engineers to model their strengthened structures and solve their problems.Keywords: continuous beams, debonding, finite element, fibre reinforced polymer
Procedia PDF Downloads 48220023 High Performance Computing and Big Data Analytics
Authors: Branci Sarra, Branci Saadia
Abstract:
Because of the multiplied data growth, many computer science tools have been developed to process and analyze these Big Data. High-performance computing architectures have been designed to meet the treatment needs of Big Data (view transaction processing standpoint, strategic, and tactical analytics). The purpose of this article is to provide a historical and global perspective on the recent trend of high-performance computing architectures especially what has a relation with Analytics and Data Mining.Keywords: high performance computing, HPC, big data, data analysis
Procedia PDF Downloads 520