Search results for: Dynamic Mode Decomposition (DMD)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6161

Search results for: Dynamic Mode Decomposition (DMD)

3731 Management Trainee Program

Authors: Ambreen Amir Ali

Abstract:

In todays’ dynamic environment, it has become very crucial to have comprehensive management trainee program to hire future leaders of organization. It is being proved that fresh graduates mostly join organizations because of its institution but later on they leave organization because of their immediate manager or supervisor. The concept of coaching and mentoring in talent management systems are very important, because mentors are those who can advise, facilitate, help and support new entrants to advance in their career. When it comes to going for talent hunt, one point needs to be highlighted that MTs are the raw talent for your organization, now it’s the responsibility of employers to nourish them, polish and developed them so that they can enthusiastically take care of senior leadership roles.

Keywords: management trainee, retention, leadership roles, coaching

Procedia PDF Downloads 619
3730 Balancing Rule of Law, Human Rights and Governance

Authors: Torkan Jabbariraad

Abstract:

This study explores the role of private regulation as a mode of governance that engages non-state actors in establishing and implementing rules or standards for public goods or services. It examines the various forms, functions, and effects of private regulation on the rule of law and human rights and considers the role and duties of public authorities in monitoring and supporting private regulation. It contends that private regulation should be regarded as a beneficial supplement to public regulation rather than a substitute or rival and that public authorities should find a balance between acknowledging the independence and variety of private actors and securing their accountability and legitimacy. It also recommends that applying the principles and values of good governance to private regulation can improve its quality and efficiency. The study relies on various sources and viewpoints from the literature on governance theory, public law, and human rights and suggests further research and discussion on the topic of private regulation and its consequences for society.

Keywords: private regulation, public authority, governance theory, rule of law, human rights

Procedia PDF Downloads 27
3729 Life Cycle Assessment in Road Pavements: A Literature Review and the Potential Use in Brazil

Authors: B. V. Santos, M. T. M. Carvalho, J. H. S. Rêgo

Abstract:

The article presents a literature review on recent advances related to studies of the environmental impact of road pavements, with reference to the concepts of Life Cycle Assessment (LCA). An introduction with the main motivations for the development of the research is presented, with a current overview of the Brazilian transport infrastructure and the projections for the road mode for the coming years, and the possibility of using the referred methodology by the road sector in Brazil. The article explores the origin of LCA in road pavements and the details linked to its implementation from the perspective of the four main phases of the study (goal and scope definition, inventory analysis, impact assessment, and interpretation). Finally, the main advances and deficiencies observed in the selected studies are gathered, with the proposition of research fields that can be explored in future national or international studies of LCA of road pavements.

Keywords: Brazil, life cycle assessment, road pavements, sustainable

Procedia PDF Downloads 66
3728 Autonomic Threat Avoidance and Self-Healing in Database Management System

Authors: Wajahat Munir, Muhammad Haseeb, Adeel Anjum, Basit Raza, Ahmad Kamran Malik

Abstract:

Databases are the key components of the software systems. Due to the exponential growth of data, it is the concern that the data should be accurate and available. The data in databases is vulnerable to internal and external threats, especially when it contains sensitive data like medical or military applications. Whenever the data is changed by malicious intent, data analysis result may lead to disastrous decisions. Autonomic self-healing is molded toward computer system after inspiring from the autonomic system of human body. In order to guarantee the accuracy and availability of data, we propose a technique which on a priority basis, tries to avoid any malicious transaction from execution and in case a malicious transaction affects the system, it heals the system in an isolated mode in such a way that the availability of system would not be compromised. Using this autonomic system, the management cost and time of DBAs can be minimized. In the end, we test our model and present the findings.

Keywords: autonomic computing, self-healing, threat avoidance, security

Procedia PDF Downloads 491
3727 E-Learning in Life-Long Learning: Best Practices from the University of the Aegean

Authors: Chryssi Vitsilaki, Apostolos Kostas, Ilias Efthymiou

Abstract:

This paper presents selected best practices on online learning and teaching derived from a novel and innovating Lifelong Learning program through e-Learning, which has during the last five years been set up at the University of the Aegean in Greece. The university, capitalizing on an award-winning, decade-long experience in e-learning and blended learning in undergraduate and postgraduate studies, recently expanded into continuous education and vocational training programs in various cutting-edge fields. So, in this article we present: (a) the academic structure/infrastructure which has been developed for the administrative, organizational and educational support of the e-Learning process, including training the trainers, (b) the mode of design and implementation based on a sound pedagogical framework of open and distance education, and (c) the key results of the assessment of the e-learning process by the participants, as they are used to feedback on continuous organizational and teaching improvement and quality control.

Keywords: distance education, e-learning, life-long programs, synchronous/asynchronous learning

Procedia PDF Downloads 316
3726 Impact Load Response of Light Rail Train Rail Guard

Authors: Eyob Hundessa Gose

Abstract:

Nowadays, it is obviously known that the construction of different infrastructures is one measurement of the development of a country; infrastructures like buildings, bridges, roads, and railways are among them. In the capital city of Ethiopia, the so-called Addis Ababa, the Light Rail Train (LRT), was built Four years ago to satisfy the demand for transportation among the people in the city. The lane of the Train and vehicle separation Media was built with a curb and rail guard installation system to show the right-of-way and for protection of vehicles entering the Train Lane, but this Rail guard fails easily when impacted by vehicles and found that the impact load response of the Rail guard is weak and the Rail guard cannot withstand impact load. This study investigates the effect of variation of parameters such as vehicle speed and different mass effects and assesses the failure mode FRP and Steel reinforcement bar rail guards of deflection and damage state.

Keywords: impact load, fiber reinforced polymer, rail guard, LS-DYNA

Procedia PDF Downloads 46
3725 Graphene Metamaterials Supported Tunable Terahertz Fano Resonance

Authors: Xiaoyong He

Abstract:

The manipulation of THz waves is still a challenging task due to lack of natural materials interacted with it strongly. Designed by tailoring the characters of unit cells (meta-molecules), the advance of metamaterials (MMs) may solve this problem. However, because of Ohmic and radiation losses, the performance of MMs devices is subjected to the dissipation and low quality factor (Q-factor). This dilemma may be circumvented by Fano resonance, which arises from the destructive interference between a bright continuum mode and dark discrete mode (or a narrow resonance). Different from symmetric Lorentz spectral curve, Fano resonance indicates a distinct asymmetric line-shape, ultrahigh quality factor, steep variations in spectrum curves. Fano resonance is usually realized through symmetry breaking. However, if concentric double rings (DR) are placed closely to each other, the near-field coupling between them gives rise to two hybridized modes (bright and narrowband dark modes) because of the local asymmetry, resulting into the characteristic Fano line shape. Furthermore, from the practical viewpoint, it is highly desirable requirement that to achieve the modulation of Fano spectral curves conveniently, which is an important and interesting research topics. For current Fano systems, the tunable spectral curves can be realized by adjusting the geometrical structural parameters or magnetic fields biased the ferrite-based structure. But due to limited dispersion properties of active materials, it is still a tough work to tailor Fano resonance conveniently with the fixed structural parameters. With the favorable properties of extreme confinement and high tunability, graphene is a strong candidate to achieve this goal. The DR-structure possesses the excitation of so-called “trapped modes,” with the merits of simple structure and high quality of resonances in thin structures. By depositing graphene circular DR on the SiO2/Si/ polymer substrate, the tunable Fano resonance has been theoretically investigated in the terahertz regime, including the effects of graphene Fermi level, structural parameters and operation frequency. The results manifest that the obvious Fano peak can be efficiently modulated because of the strong coupling between incident waves and graphene ribbons. As Fermi level increases, the peak amplitude of Fano curve increases, and the resonant peak position shifts to high frequency. The amplitude modulation depth of Fano curves is about 30% if Fermi level changes in the scope of 0.1-1.0 eV. The optimum gap distance between DR is about 8-12 μm, where the value of figure of merit shows a peak. As the graphene ribbon width increases, the Fano spectral curves become broad, and the resonant peak denotes blue shift. The results are very helpful to develop novel graphene plasmonic devices, e.g. sensors and modulators.

Keywords: graphene, metamaterials, terahertz, tunable

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3724 Developing Granular Sludge and Maintaining High Nitrite Accumulation for Anammox to Treat Municipal Wastewater High-efficiently in a Flexible Two-stage Process

Authors: Zhihao Peng, Qiong Zhang, Xiyao Li, Yongzhen Peng

Abstract:

Nowadays, conventional nitrogen removal process (nitrification and denitrification) was adopted in most wastewater treatment plants, but many problems have occurred, such as: high aeration energy consumption, extra carbon sources dosage and high sludge treatment costs. The emergence of anammox has bring about the great revolution to the nitrogen removal technology, and only the ammonia and nitrite were required to remove nitrogen autotrophically, no demand for aeration and sludge treatment. However, there existed many challenges in anammox applications: difficulty of biomass retention, insufficiency of nitrite substrate, damage from complex organic etc. Much effort was put into the research in overcoming the above challenges, and the payment was rewarded. It was also imperative to establish an innovative process that can settle the above problems synchronously, after all any obstacle above mentioned can cause the collapse of anammox system. Therefore, in this study, a two-stage process was established that the sequencing batch reactor (SBR) and upflow anaerobic sludge blanket (UASB) were used in the pre-stage and post-stage, respectively. The domestic wastewater entered into the SBR first and went through anaerobic/aerobic/anoxic (An/O/A) mode, and the draining at the aerobic end of SBR was mixed with domestic wastewater, the mixture then entering to the UASB. In the long term, organic and nitrogen removal performance was evaluated. All along the operation, most COD was removed in pre-stage (COD removal efficiency > 64.1%), including some macromolecular organic matter, like: tryptophan, tyrosinase and fulvic acid, which could weaken the damage of organic matter to anammox. And the An/O/A operating mode of SBR was beneficial to the achievement and maintenance of partial nitrification (PN). Hence, sufficient and steady nitrite supply was another favorable condition to anammox enhancement. Besides, the flexible mixing ratio helped to gain a substrate ratio appropriate to anammox (1.32-1.46), which further enhance the anammox. Further, the UASB was used and gas recirculation strategy was adopted in the post-stage, aiming to achieve granulation by the selection pressure. As expected, the granules formed rapidly during 38 days, which increased from 153.3 to 354.3 μm. Based on bioactivity and gene measurement, the anammox metabolism and abundance level rose evidently, by 2.35 mgN/gVss·h and 5.3 x109. The anammox bacteria mainly distributed in the large granules (>1000 μm), while the biomass in the flocs (<200 μm) and microgranules (200-500 μm) barely displayed anammox bioactivity. Enhanced anammox promoted the advanced autotrophic nitrogen removal, which increased from 71.9% to 93.4%, even when the temperature was only 12.9 ℃. Therefore, it was feasible to enhance anammox in the multiple favorable conditions created, and the strategy extended the application of anammox to the full-scale mainstream, enhanced the understanding of anammox in the aspects of culturing conditions.

Keywords: anammox, granules, nitrite accumulation, nitrogen removal efficiency

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3723 Experimental Study of the Antibacterial Activity and Modeling of Non-isothermal Crystallization Kinetics of Sintered Seashell Reinforced Poly(Lactic Acid) And Poly(Butylene Succinate) Biocomposites Planned for 3D Printing

Authors: Mohammed S. Razali, Kamel Khimeche, Dahah Hichem, Ammar Boudjellal, Djamel E. Kaderi, Nourddine Ramdani

Abstract:

The use of additive manufacturing technologies has revolutionized various aspects of our daily lives. In particular, 3D printing has greatly advanced biomedical applications. While fused filament fabrication (FFF) technologies have made it easy to produce or prototype various medical devices, it is crucial to minimize the risk of contamination. New materials with antibacterial properties, such as those containing compounded silver nanoparticles, have emerged on the market. In a previous study, we prepared a newly sintered seashell filler (SSh) from bio-based seashells found along the Mediterranean coast using a suitable heat treatment process. We then prepared a series of polylactic acid (PLA) and polybutylene succinate (PBS) biocomposites filled with these SSh particles using a melt mixing technique with a twin-screw extruder to use them as feedstock filaments for 3D printing. The study consisted of two parts: evaluating the antibacterial activity of newly prepared biocomposites made of PLA and PBS reinforced with a sintered seashell in the first part and experimental and modeling analysis of the non-isothermal crystallization kinetics of these biocomposites in the second part. In the first part, the bactericidal activity of the biocomposites against three different bacteria, including Gram-negative bacteria such as (E. coli and Pseudomonas aeruginosa), as well as Gram-positive bacteria such as (Staphylococcus aureus), was examined. The PLA-based biocomposite containing 20 wt.% of SSh particles exhibited an inhibition zone with radial diameters of 8mm and 6mm against E. coli and Pseudo. Au, respectively, while no bacterial activity was observed against Staphylococcus aureus. In the second part, the focus was on investigating the effect of the sintered seashell filler particles on the non-isothermal crystallization kinetics of PLA and PBS 3D-printing composite materials. The objective was to understand the impact of the filler particles on the crystallization mechanism of both PLA and PBS during the cooling process of a melt-extruded filament in (FFF) to manage the dimensional accuracy and mechanical properties of the final printed part. We conducted a non-isothermal melt crystallization kinetic study of a series of PLA-SS and PBS-SS composites using differential scanning calorimetry at various cooling rates. We analyzed the obtained kinetic data using different crystallization kinetic models such as modified Avrami, Ozawa, and Mo's methods. Dynamic mode describes the relative crystallinity as a function of temperature; it found that time half crystallinity (t1/2) of neat PLA decreased from 17 min to 7.3 min for PLA+5 SSh and the (t1/2) of virgin PBS was reduced from 3.5 min to 2.8 min for the composite containing 5wt.% of SSh. We found that the coated SS particles with stearic acid acted as nucleating agents and had a nucleation activity, as observed through polarized optical microscopy. Moreover, we evaluated the effective energy barrier of the non-isothermal crystallization process using the Iso conversional methods of Flynn-Wall-Ozawa (F-W-O) and Kissinger-Akahira-Sunose (K-A-S). The study provides significant insights into the crystallization behavior of PLA and PBS biocomposites.

Keywords: avrami model, bio-based reinforcement, dsc, gram-negative bacteria, gram-positive bacteria, isoconversional methods, non-isothermal crystallization kinetics, poly(butylene succinate), poly(lactic acid), antbactirial activity

Procedia PDF Downloads 61
3722 Direct Power Control Applied on 5-Level Diode Clamped Inverter Powered by a Renewable Energy Source

Authors: A. Elnady

Abstract:

This paper presents an improved Direct Power Control (DPC) scheme applied to the multilevel inverter that forms a Distributed Generation Unit (DGU). This paper demonstrates the performance of active and reactive power injected by the DGU to the smart grid. The DPC is traditionally operated by the hysteresis controller with the Space Vector Modulation (SVM) which is applied on the 2-level inverters or 3-level inverters. In this paper, the DPC is operated by the PI controller with the Phase-Disposition Pulse Width Modulation (PD-PWM) applied to the 5-level diode clamped inverter. The new combination of the DPC, PI controller, PD-PWM and multilevel inverter proves that its performance is much better than the conventional hysteresis-SVM based DPC. Simulations results have been presented to validate the performance of the suggested control scheme in the grid-connected mode.

Keywords: direct power control, PI controller, PD-PWM, and power control

Procedia PDF Downloads 225
3721 Formulation and Evaluation of Dispersible Tablet of Furosemide for Pediatric Use

Authors: O. Benaziz, A. Dorbane, S. Djeraba

Abstract:

The objective of this work is to formulate a dry dispersible form of furosemide in the context of pediatric dose adjustment. To achieve this, we have produced a set of formulas that will be tested in process and after compression. The formula with the best results will be improved to optimize the final shape of the product. Furosemide is the most widely used pediatric diuretic because of its low toxicity. The manufacturing process was chosen taking into account all the data relating to the active ingredient and the excipients used and complying with the specifications and requirements of dispersible tablets. The process used to prepare these tablets was wet granulation. Different excipients were used: lactose, maize starch, magnesium stearate and two superdisintegrants. The mode of incorporation of super-disintegrant changes with each formula. The use of super-disintegrant in the formula allowed optimization of the disintegration time. Prepared tablets were evaluated for weight, content uniformity, hardness, disintegration time, friability and in vitro dissolution test. 

Keywords: formulation, dispersible tablets, wet granulation, superdisintegrants, disintegration

Procedia PDF Downloads 331
3720 An Algorithm for Estimating the Stable Operation Conditions of the Synchronous Motor of the Ore Mill Electric Drive

Authors: M. Baghdasaryan, A. Sukiasyan

Abstract:

An algorithm for estimating the stable operation conditions of the synchronous motor of the ore mill electric drive is proposed. The stable operation conditions of the synchronous motor are revealed, taking into account the estimation of the q angle change and the technological factors. The stability condition obtained allows to ensure the stable operation of the motor in the synchronous mode, taking into account the nonlinear character of the mill loading. The developed algorithm gives an opportunity to present the undesirable phenomena, arising in the electric drive system. The obtained stability condition can be successfully applied for the optimal control of the electromechanical system of the mill.

Keywords: electric drive, synchronous motor, ore mill, stability, technological factors

Procedia PDF Downloads 410
3719 Evaluation of Anti-Cancer Activities of Formononetin in Lung Cancer by in vitro Methods

Authors: Vishnu Varthan Vaithiyalingam Jagannathan, Lakshmi Karunanidhi Santhanalakshmi, Srividya Ammayappan Rajam

Abstract:

Formononetin is the O-Methoxy Flavonol that has many pharmacological activities, which belongs to the flavonoid family. In the current study, activity of this molecule was evaluated in lung cancer cell lines. In general, flavonoids possess certain anticancer mechanism. Being a flavonoid subfamily, this molecule was subjected to evaluate cytotoxicity assay by MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide)) stain, mode of cell death assay stained by acridine orange and ethidium bromide and Evaluation of Apoptosis pathway (extrinsic or intrinsic) by Caspase 3/7 stain and Rhodamine-123 stain. From the results, we could able to confirm that the investigatory molecule formononetin has anticancer activity and in future, the study will propose to evaluate the formononetin action against genetic changes occurs during lung cancer progression.

Keywords: Caspase 3/7, formononetin, lung cancer, Rhodamine-123

Procedia PDF Downloads 199
3718 Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber

Authors: Abbas Vahedian, Rijun Shrestha, Keith Crews

Abstract:

The bond mechanism between timber and fibre reinforced polymer (FRP) is relatively complex and is influenced by a number of variables including bond thickness, bond width, bond length, material properties, and geometries. This study investigates the influence of bond thickness on the behaviour of interface, failure mode, and bond strength of externally bonded FRP-to-timber interface. In the present study, 106 single shear joint specimens have been investigated. Experiment results showed that higher layers of FRP increase the ultimate load carrying capacity of interface; conversely, such increase led to decrease the slip of interface. Moreover, samples with more layers of FRPs may fail in a brittle manner without noticeable warning that collapse is imminent.

Keywords: fibre reinforced polymer, FRP, single shear test, bond thickness, bond strength

Procedia PDF Downloads 216
3717 Performance of Bimetallic Catalyst in the Oxidation of Volatile Organic Compounds

Authors: Faezeh Aghazadeh

Abstract:

The catalytic activity of Pt/γ-Al₂O₃ and Pt-Fe/γ-Al₂O₃ catalysts was investigated to bring about the complete oxidation of 2-Propanol. Among them, Pt-Fe/γ-Al₂O₃ was found to be the most promising catalyst based on activity. The catalysts were characterized by (XRD), (SEM), (TEM) and ICP-AES techniques. Iron loadings on Pt/γ-Al₂O₃ had a great effect on catalytic activity, and Pt-Fe/γ-Al₂O₃ (1.75 wt% Fe) catalyst at calcination temperature 300°C was observed to be the most active, which might be contributed to the favorable synergetic effects between Pt and Fe, high activity and the well-dispersed bimetallic phase. The combustion of 2-Propanol in the vapor phase was carried out in a conventional flow U-shape glass reactor used in the differential mode at atmospheric pressure. 2-Propanol was analyzed by a gas chromatograph VARIAN 3800 CX equipped with an FID. As observed, better performance and activity were observed for Pt-Fe/Al₂O₃ bimetallic catalyst. These results indicate that the high dispersion on support gives a positive effect on catalytic activity.

Keywords: volatile organic compounds, bimetallic catalyst, catalytic activity, low temperature

Procedia PDF Downloads 127
3716 Flexural Response of Sandwiches with Micro Lattice Cores Manufactured via Selective Laser Sintering

Authors: Emre Kara, Ali Kurşun, Halil Aykul

Abstract:

The lightweight sandwiches obtained with the use of various core materials such as foams, honeycomb, lattice structures etc., which have high energy absorbing capacity and high strength to weight ratio, are suitable for several applications in transport industry (automotive, aerospace, shipbuilding industry) where saving of fuel consumption, load carrying capacity increase, safety of vehicles and decrease of emission of harmful gases are very important aspects. While the sandwich structures with foams and honeycombs have been applied for many years, there is a growing interest on a new generation sandwiches with micro lattice cores. In order to produce these core structures, various production methods were created with the development of the technology. One of these production technologies is an additive manufacturing technique called selective laser sintering/melting (SLS/SLM) which is very popular nowadays because of saving of production time and achieving the production of complex topologies. The static bending and the dynamic low velocity impact tests of the sandwiches with carbon fiber/epoxy skins and the micro lattice cores produced via SLS/SLM were already reported in just a few studies. The goal of this investigation was the analysis of the flexural response of the sandwiches consisting of glass fiber reinforced plastic (GFRP) skins and the micro lattice cores manufactured via SLS under thermo-mechanical loads in order to compare the results in terms of peak load and absorbed energy values respect to the effect of core cell size, temperature and support span length. The micro lattice cores were manufactured using SLS technology that creates the product drawn by a 3D computer aided design (CAD) software. The lattice cores which were designed as body centered cubic (BCC) model having two different cell sizes (d= 2 and 2.5 mm) with the strut diameter of 0.3 mm were produced using titanium alloy (Ti6Al4V) powder. During the production of all the core materials, the same production parameters such as laser power, laser beam diameter, building direction etc. were kept constant. Vacuum Infusion (VI) method was used to produce skin materials, made of [0°/90°] woven S-Glass prepreg laminates. The combination of the core and skins were implemented under VI. Three point bending tests were carried out by a servo-hydraulic test machine with different values of support span distances (L = 30, 45, and 60 mm) under various temperature values (T = 23, 40 and 60 °C) in order to analyze the influences of support span and temperature values. The failure mode of the collapsed sandwiches has been investigated using 3D computed tomography (CT) that allows a three-dimensional reconstruction of the analyzed object. The main results of the bending tests are: load-deflection curves, peak force and absorbed energy values. The results were compared according to the effect of cell size, support span and temperature values. The obtained results have particular importance for applications that require lightweight structures with a high capacity of energy dissipation, such as the transport industry, where problems of collision and crash have increased in the last years.

Keywords: light-weight sandwich structures, micro lattice cores, selective laser sintering, transport application

Procedia PDF Downloads 325
3715 Metabolic Cost and Perceived Exertion during Progressive and Randomized Walking Protocols

Authors: Simeon E. H. Davies

Abstract:

This study investigated whether selected metabolic responses and the perception of effort varied during four different walk protocols where speed increased progressively 3, 4, 5, 6, and 7 km/hr (progressive treadmill walk (PTW); and progressive land walk (PLW); or where the participant adjusted to random changes of speed e.g. 6, 3, 7, 4, and 5 km/hr during a randomized treadmill walk (RTW); and a randomized land walk (RLW). Mean stature and mass of the seven participants was 1.75m and 70kg respectively, with a mean body fat of 15%. Metabolic measures including heart rate, relative oxygen uptake, ventilation, increased in a linear fashion up to 6 km/hr, however at 7 km/hr there was a significant increase in metabolic response notably during the PLW, and to a similar, although lesser extent in RLW, probably as a consequence of the loss of kinetic energy when turning at each cone in order to maintain the speed during each shuttle. Respiration frequency appeared to be a more sensitive indicator of physical exertion, exhibiting a rapid elevation at 5 km/hr. The perception of effort during each mode and at each speed was largely congruent during each walk protocol.

Keywords: exertion, metabolic, progressive, random, walking

Procedia PDF Downloads 445
3714 Devulcanization of Waste Rubber Tyre Utilizing Deep Eutectic Solvents and Ultrasonic Energy

Authors: Ricky Saputra, Rashmi Walvekar, Mohammad Khalid, Kaveh Shahbaz, Suganti Ramarad

Abstract:

This particular study of interest aims to study the effect of coupling ultrasonic treatment with eutectic solvents in devulcanization process of waste rubber tyre. Specifically, three different types of Deep Eutectic Solvents (DES) were utilized, namely ChCl:Urea (1:2), ChCl:ZnCl₂ (1:2) and ZnCl₂:urea (2:7) in which their physicochemical properties were analysed and proven to have permissible water content that is less than 3.0 wt%, degradation temperature below 200ᵒC and freezing point below 60ᵒC. The mass ratio of rubber to DES was varied from 1:20-1:40, sonicated for 1 hour at 37 kHz and heated at variable time of 5-30 min at 180ᵒC. Energy dispersive x-rays (EDX) results revealed that the first two DESs give the highest degree of sulphur removal at 74.44 and 76.69% respectively with optimum heating time at 15 minutes whereby if prolonged, reformation of crosslink network would be experienced. Such is supported by the evidence shown by both FTIR and FESEM results where di-sulfide peak reappears at 30 minutes and morphological structures from 15 to 30 minutes change from smooth with high voidage to rigid with low voidage respectively. Furthermore, TGA curve reveals similar phenomena whereby at 15 minutes thermal decomposition temperature is at the lowest due to the decrease of molecular weight as a result of sulphur removal but increases back at 30 minutes. Type of bond change was also analysed whereby it was found that only di-sulphide bond was cleaved and which indicates partial-devulcanization. Overall, the results show that DES has a great potential to be used as devulcanizing solvent.

Keywords: crosslink network, devulcanization, eutectic solvents, reformation, ultrasonic

Procedia PDF Downloads 163
3713 Physics-Based Earthquake Source Models for Seismic Engineering: Analysis and Validation for Dip-Slip Faults

Authors: Percy Galvez, Anatoly Petukhin, Paul Somerville, Ken Miyakoshi, Kojiro Irikura, Daniel Peter

Abstract:

Physics-based dynamic rupture modelling is necessary for estimating parameters such as rupture velocity and slip rate function that are important for ground motion simulation, but poorly resolved by observations, e.g. by seismic source inversion. In order to generate a large number of physically self-consistent rupture models, whose rupture process is consistent with the spatio-temporal heterogeneity of past earthquakes, we use multicycle simulations under the heterogeneous rate-and-state (RS) friction law for a 45deg dip-slip fault. We performed a parametrization study by fully dynamic rupture modeling, and then, a set of spontaneous source models was generated in a large magnitude range (Mw > 7.0). In order to validate rupture models, we compare the source scaling relations vs. seismic moment Mo for the modeled rupture area S, as well as average slip Dave and the slip asperity area Sa, with similar scaling relations from the source inversions. Ground motions were also computed from our models. Their peak ground velocities (PGV) agree well with the GMPE values. We obtained good agreement of the permanent surface offset values with empirical relations. From the heterogeneous rupture models, we analyzed parameters, which are critical for ground motion simulations, i.e. distributions of slip, slip rate, rupture initiation points, rupture velocities, and source time functions. We studied cross-correlations between them and with the friction weakening distance Dc value, the only initial heterogeneity parameter in our modeling. The main findings are: (1) high slip-rate areas coincide with or are located on an outer edge of the large slip areas, (2) ruptures have a tendency to initiate in small Dc areas, and (3) high slip-rate areas correlate with areas of small Dc, large rupture velocity and short rise-time.

Keywords: earthquake dynamics, strong ground motion prediction, seismic engineering, source characterization

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3712 Precarious Employment Experience; Developing a Precariousness Scale

Authors: Gul Selin Erben

Abstract:

Precariousness can be evaluated as the new employment climate of the neo-liberal employment markets. As the word refers to a new mode of employment experience and working practices, it was felt as a necessity to reveal the basic characteristics of this kind of employment experience. Furthermore, according to the literature, precarious employment practices have some negative outcomes such as alienation, sense of anger, and anomy. Thus, it has quite significant to reveal the conditions' characteristics and practices of precarious employment. This study has the purpose to develop an instrument which measures the precarious employment practices. In order to develop a precariousness scale, the relevant literature was examined, and 30 statements were established as a result of the literature review. The development and validation of the scale were done by a sample of 123 individuals who work in different sectors in İstanbul as a white color employee. Convenience sampling was used as a sampling methodology. Reliability and factor analysis were conducted. As a result of the exploratory factor analysis, 3 dimensions were gathered.

Keywords: employment, employment experience, precariousness, scale development

Procedia PDF Downloads 153
3711 Treatment of Leaden Sludge of Algiers Refinery by Electrooxidation

Authors: K. Ighilahriz, M. Taleb Ahmed, R. Maachi

Abstract:

Oil industries are responsible for most cases of contamination of our ecosystem by oil and heavy metals. They are toxic and considered carcinogenic and dangerous even when they exist in trace amounts. At Algiers refinery, production, transportation, and refining of crude oil generate considerable waste in storage tanks; these residues result from the gravitational settling. The composition of these residues is essentially a mixture of hydrocarbon and lead. We propose in this work the application of electrooxidation treatment for the leachate of the leaden sludge. The effect of pH, current density and the electrolysis time were studied, the effectiveness of the processes is evaluated by measuring the chemical oxygen demand (COD). The dissolution is the best way to mobilize pollutants from leaden mud, so we conducted leaching before starting the electrochemical treatment. The process was carried out in batch mode using graphite anode and a stainless steel cathode. The results clearly demonstrate the compatibility of the technique used with the type of pollution studied. In fact, it allowed COD removal about 80%.

Keywords: electrooxidation, leaching, leaden sludge, oil industry

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3710 Hardy Type Inequalities of Two-Dimensional on Time Scales via Steklov Operator

Authors: Wedad Albalawi

Abstract:

The mathematical inequalities have been the core of mathematical study and used in almost all branches of mathematics as well in various areas of science and engineering. The inequalities by Hardy, Littlewood and Polya were the first significant composition of several science. This work presents fundamental ideas, results and techniques and it has had much influence on research in various branches of analysis. Since 1934, various inequalities have been produced and studied in the literature. Furthermore, some inequalities have been formulated by some operators; in 1989, weighted Hardy inequalities have been obtained for integration operators. Then, they obtained weighted estimates for Steklov operators that were used in the solution of the Cauchy problem for the wave equation. They were improved upon in 2011 to include the boundedness of integral operators from the weighted Sobolev space to the weighted Lebesgue space. Some inequalities have been demonstrated and improved using the Hardy–Steklov operator. Recently, a lot of integral inequalities have been improved by differential operators. Hardy inequality has been one of the tools that is used to consider integrity solutions of differential equations. Then dynamic inequalities of Hardy and Coposon have been extended and improved by various integral operators. These inequalities would be interesting to apply in different fields of mathematics (functional spaces, partial differential equations, mathematical modeling). Some inequalities have been appeared involving Copson and Hardy inequalities on time scales to obtain new special version of them. A time scale is defined as a closed subset contains real numbers. Then the inequalities of time scales version have received a lot of attention and has had a major field in both pure and applied mathematics. There are many applications of dynamic equations on time scales to quantum mechanics, electrical engineering, neural networks, heat transfer, combinatorics, and population dynamics. This study focuses on double integrals to obtain new time-scale inequalities of Copson driven by Steklov operator. They will be applied in the solution of the Cauchy problem for the wave equation. The proof can be done by introducing restriction on the operator in several cases. In addition, the obtained inequalities done by using some concepts in time scale version such as time scales calculus, theorem of Fubini and the inequality of H¨older.

Keywords: time scales, inequality of Hardy, inequality of Coposon, Steklov operator

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3709 Acoustic Radiation from an Infinite Cylindrical Shell with Periodic Lengthwise Ribs

Authors: Yunzhe Tong, Jun Fan, Bin Wang

Abstract:

The vibroacoustic behavior of an immersed infinite cylindrical shell with periodic lengthwise ribs has been studied in this paper. The motions of the shell are described by the Donnell equations. Each lengthwise rib is modeled as an elastic beam. The motions of the bulkheads are decomposed into the longitudinal motions and flexural motions. The analytical expressions of the shell motions can be obtained through circumferential mode expansion, Fourier Transform and periodic boundary condition in the circumferential direction. Furthermore, the far-field radiated pressure has been obtained using the stationary phase. The analysis of wavenumber domain shows that periodic lengthwise stiffeners in the circumferential direction can produce flexural Bloch waves. The dominant feature in far-field pressure amplitude is the resonance of the supersonic components of the flexural Bloch waves in the circumferential direction.

Keywords: flexural Bloch wave, stiffened shell, vibroacoustics, wavenumber analysis

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3708 Magnetic Cellulase/Halloysite Nanotubes as Biocatalytic System for Converting Agro-Waste into Value-Added Product

Authors: Devendra Sillu, Shekhar Agnihotri

Abstract:

The 'nano-biocatalyst' utilizes an ordered assembling of enzyme on to nanomaterial carriers to catalyze desirable biochemical kinetics and substrate selectivity. The current study describes an inter-disciplinary approach for converting agriculture waste, sugarcane bagasse into D-glucose exploiting halloysite nanotubes (HNTs) decorated cellulase enzyme as nano-biocatalytic system. Cellulase was successfully immobilized on HNTs employing polydopamine as an eco-friendly crosslinker while iron oxide nanoparticles were attached to facilitate magnetic recovery of material. The characterization studies (UV-Vis, TEM, SEM, and XRD) displayed the characteristic features of both cellulase and magnetic HNTs in the resulting nanocomposite. Various factors (i.e., working pH, temp., crosslinker conc., enzyme conc.) which may influence the activity of biocatalytic system were investigated. The experimental design was performed using Response Surface Methodology (RSM) for process optimization. Analyses data demonstrated that the nanobiocatalysts retained 80.30% activity even at elevated temperature (55°C) and excellent storage stabilities after 10 days. The repeated usage of system revealed a remarkable consistent relative activity over several cycles. The immobilized cellulase was employed to decompose agro-waste and the maximum decomposition rate of 67.2 % was achieved. Conclusively, magnetic HNTs can serve as a potential support for enzyme immobilization with long term usage, good efficacy, reusability and easy recovery from solution.

Keywords: halloysite nanotubes, enzyme immobilization, cellulase, response surface methodology, magnetic recovery

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3707 Condition Monitoring for Controlling the Stability of the Rotating Machinery

Authors: A. Chellil, I. Gahlouz, S. Lecheb, A. Nour, S. Chellil, H. Mechakra, H. Kebir

Abstract:

In this paper, the experimental study for the instability of a separator rotor is presented, under dynamic loading response in the harmonic analysis condition. The analysis of the stress which operates the rotor is done. Calculations of different energies and the virtual work of the aerodynamic loads from the rotor are developed. Numerical calculations on the model develop of three dimensions prove that the defects effect has a negative effect on the stability of the rotor. Experimentally, the study of the rotor in the transient system allowed to determine the vibratory responses due to the unbalances and various excitations.

Keywords: rotor, frequency, finite element, specter

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3706 Exploring the Dynamic Identities of Multilingual Adolescents in Contexts of L3+ Learning in Four European Sites

Authors: Harper Staples

Abstract:

A necessary outcome of today’s contemporary globalised reality, current views of multilingualism hold that it no longer represents the exception, but rather the rule. As such, the simultaneous acquisition of multiple languages represents a common experience for many of today's students and therefore represents a key area of inquiry in the domain of foreign language learner identity. Second and multilingual language acquisition processes parallel each other in many ways; however, there are differences to be found in the ways in which a student may learn a third language. A multilingual repertoire will have to negotiate complex change as language competencies dynamically evolve; moreover, this process will vary according to the contextual factors attributed to a unique learner. A developing multilingual identity must, therefore, contend with an array of potential challenges specific to the individual in question. Despite an overarching recognition in the literature that pluri-language acquisition represents a unique field of inquiry within applied linguistic research, there is a paucity of empirical work which examines the ways in which individuals construct a sense of their own identity as multilingual speakers in such contexts of learning. This study explores this phenomenon via a mixed-methods, comparative case study approach at four school sites based in Finland, France, Wales, and England. It takes a strongly individual-in-context view, conceptualising each adolescent participant in dynamic terms in order to undertake a holistic exploration of the myriad factors that might impact upon, and indeed be impacted by, a learner's developing multilingual identity. Emerging themes of note thus far suggest that, beyond the expected divergences in the experience of multilinguality at the individual level, there are contradictions in the way in which adolescent students in each site 'claim' their plurilingualism. This can be argued to be linked to both meso and macro-level factors, including the foreign language curriculum and, more broadly, societal attitudes towards multilingualism. These diverse emergent identifications have implications not only for attainment in the foreign language but also for student well-being more generally.

Keywords: foreign language learning, student identity, multilingualism, educational psychology

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3705 Parametric Analysis of Water Lily Shaped Split Ring Resonator Loaded Fractal Monopole Antenna for Multiband Applications

Authors: C. Elavarasi, T. Shanmuganantham

Abstract:

A coplanar waveguide (CPW) feed is presented, and comprising a split ring resonator (SRR) loaded fractal with water lily shape is used for multi band applications. The impedance matching of the antenna is determined by the number of Koch curve fractal unit cells. The antenna is designed on a FR4 substrate with a permittivity of εr = 4.4 and size of 14 x 16 x 1.6 mm3 to generate multi resonant mode at 3.8 GHz covering S band, 8.68 GHz at X band, 13.96 GHz at Ku band, and 19.74 GHz at K band with reflection coefficient better than -10 dB. Simulation results show that the antenna exhibits the desired voltage standing wave ratio (VSWR) level and radiation patterns across the wide frequency range. The fundamental parameters of the antenna such as return loss, VSWR, good radiation pattern with reasonable gain across the operating bands are obtained.

Keywords: fractal, metamaterial, split ring resonator, waterlily shape

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3704 The HSBC Building in Shanghai: Diverse Styles of Ornament and the Construction of a Financial Empire

Authors: Lin Ji

Abstract:

The 1923 HSBC Building is one of the landmarks of Shanghai's Bund complex and is described as "one of the finest buildings from the Suez Canal to the Bering Strait". Mr George Leopold Wilson of Palmer&Turner and his design team combine the latest British design taste with Chinese elements and bring the high standard of London manufacturing to Shanghai. This paper reviews the establishment background and construction process of the Hongkong and Shanghai Bank Corporation in Shanghai, and analyzes the characteristics of various styles and ornament of HSBC. At the same time, using the research method of iconography, compared with Britain's exploration of modern design mode in the early 20th century, we can deeply understand how this "monument of world commerce and prosperity" realizes the identity construction of its financial empire in the Far East in the perfect combination of practicality and artistry.

Keywords: early 20-century Shanghai, the bund, the HSBC building, classical styles, ornament, identity construction

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3703 The Relationship between Central Bank Independence and Inflation: Evidence from Africa

Authors: R. Bhattu Babajee, Marie Sandrine Estelle Benoit

Abstract:

The past decades have witnessed a considerable institutional shift towards Central Bank Independence across economies of the world. The motivation behind such a change is the acceptance that increased central bank autonomy has the power of alleviating inflation bias. Hence, studying whether Central Bank Independence acts as a significant factor behind the price stability in the African economies or whether this macroeconomic aim in these countries result from other economic, political or social factors is a pertinent issue. The main research objective of this paper is to assess the relationship between central bank autonomy and inflation in African economies where inflation has proved to be a serious problem. In this optic, we shall measure the degree of CBI in Africa by computing the turnover rates of central banks governors thereby studying whether decisions made by African central banks are affected by external forces. The purpose of this study is to investigate empirically the association between Central Bank Independence (CBI) and inflation for 10 African economies over a period of 17 years, from 1995 to 2012. The sample includes Botswana, Egypt, Ghana, Kenya, Madagascar, Mauritius, Mozambique, Nigeria, South Africa, and Uganda. In contrast to empirical research, we have not been using the usual static panel model for it is associated with potential mis specification arising from the absence of dynamics. To this issue a dynamic panel data model which integrates several control variables has been used. Firstly, the analysis includes dynamic terms to explain the tenacity of inflation. Given the confirmation of inflation inertia, that is very likely in African countries there exists the need for including lagged inflation in the empirical model. Secondly, due to known reverse causality between Central Bank Independence and inflation, the system generalized method of moments (GMM) is employed. With GMM estimators, the presence of unknown forms of heteroskedasticity is admissible as well as auto correlation in the error term. Thirdly, control variables have been used to enhance the efficiency of the model. The main finding of this paper is that central bank independence is negatively associated with inflation even after including control variables.

Keywords: central bank independence, inflation, macroeconomic variables, price stability

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3702 A Taxonomy of Routing Protocols in Wireless Sensor Networks

Authors: A. Kardi, R. Zagrouba, M. Alqahtani

Abstract:

The Internet of Everything (IoE) presents today a very attractive and motivating field of research. It is basically based on Wireless Sensor Networks (WSNs) in which the routing task is the major analysis topic. In fact, it directly affects the effectiveness and the lifetime of the network. This paper, developed from recent works and based on extensive researches, proposes a taxonomy of routing protocols in WSNs. Our main contribution is that we propose a classification model based on nine classes namely application type, delivery mode, initiator of communication, network architecture, path establishment (route discovery), network topology (structure), protocol operation, next hop selection and latency-awareness and energy-efficient routing protocols. In order to provide a total classification pattern to serve as reference for network designers, each class is subdivided into possible subclasses, presented, and discussed using different parameters such as purposes and characteristics.

Keywords: routing, sensor, survey, wireless sensor networks, WSNs

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