Search results for: cross phase CO₂ diffusion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9091

Search results for: cross phase CO₂ diffusion

5401 Mathematical Modeling and Algorithms for the Capacitated Facility Location and Allocation Problem with Emission Restriction

Authors: Sagar Hedaoo, Fazle Baki, Ahmed Azab

Abstract:

In supply chain management, network design for scalable manufacturing facilities is an emerging field of research. Facility location allocation assigns facilities to customers to optimize the overall cost of the supply chain. To further optimize the costs, capacities of these facilities can be changed in accordance with customer demands. A mathematical model is formulated to fully express the problem at hand and to solve small-to-mid range instances. A dedicated constraint has been developed to restrict emissions in line with the Kyoto protocol. This problem is NP-Hard; hence, a simulated annealing metaheuristic has been developed to solve larger instances. A case study on the USA-Canada cross border crossing is used.

Keywords: emission, mixed integer linear programming, metaheuristic, simulated annealing

Procedia PDF Downloads 301
5400 Valorization of a Forest Waste, Modified P-Brutia Cones, by Biosorption of Methyl Geen

Authors: Derradji Chebli, Abdallah Bouguettoucha, Abdelbaki Reffas Khalil Guediri, Abdeltif Amrane

Abstract:

The removal of Methyl Green dye (MG) from aqueous solutions using modified P-brutia cones (PBH and PBN), has been investigated work. The physical parameters such as pH, temperature, initial MG concentration, ionic strength are examined in batch experiments on the sorption of the dye. Adsorption removal of MG was conducted at natural pH 4.5 because the dye is only stable in the range of pH 3.8 to 5. It was observed in experiments that the P-brutia cones treated with NaOH (PBN) exhibited high affinity and adsorption capacity compared to the MG P-brutia cones treated with HCl (PBH) and biosorption capacity of modified P-brutia cones (PBN and PBH) was enhanced by increasing the temperature. This is confirmed by the thermodynamic parameters (ΔG° and ΔH°) which show that the adsorption of MG was spontaneous and endothermic in nature. The positive values of ΔS° suggested an irregular increase in the randomness for both adsorbent (PBN and PBH) during the adsorption process. The kinetic model pseudo-first order, pseudo-second order, and intraparticle diffusion coefficient were examined to analyze the sorption process; they showed that the pseudo-second-order model is the one that best describes the adsorption process (MG) on PBN and PBH with a correlation coefficient R²> 0.999. The ionic strength has shown that it has a negative impact on the adsorption of MG on two supports. A reduction of 68.5% of the adsorption capacity for a value Ce=30 mg/L was found for the PBH, while the PBN did not show a significant influence of the ionic strength on adsorption especially in the presence of NaCl. Among the tested isotherm models, the Langmuir isotherm was found to be the most relevant to describe MG sorption onto modified P-brutia cones with a correlation factor R²>0.999. The capacity adsorption of P-brutia cones, was confirmed for the removal of a dye, MG, from aqueous solution. We note also that P-brutia cones is a material very available in the forest and low-cost biomaterial

Keywords: adsorption, p-brutia cones, forest wastes, dyes, isotherm

Procedia PDF Downloads 371
5399 Fabrication of Periodic Graphene-Like Structure of Zinc Oxide Piezoelectric Device

Authors: Zi-Gui Huang, Shen-Hsien Hu

Abstract:

This study proposes a fabrication of phononic-crystal acoustic wave device. A graphene-like atomic structure was adopted as the main research subject, and a graphene-like structure was designed using piezoelectric material zinc oxide and its periodic boundary conditions were defined using the finite element method. The effects of a hexagonal honeycomb structure were investigated regarding the band gap phenomenon. The use of micro-electromechanical systems process technology to make the film etched micron graphics, designed to produce four kinds of different piezoelectric structure (plat, periodic, single defect and double defects). Frequency response signals and phase change were also measured in this paper.

Keywords: MEMS, phononic crystal, piezoelectric material, Zinc oxide

Procedia PDF Downloads 527
5398 Microfluidic Continuous Approaches to Produce Magnetic Nanoparticles with Homogeneous Size Distribution

Authors: Ane Larrea, Victor Sebastian, Manuel Arruebo, Jesus Santamaria

Abstract:

We present a gas-liquid microfluidic system as a reactor to obtain magnetite nanoparticles with an excellent degree of control regarding their crystalline phase, shape and size. Several types of microflow approaches were selected to prevent nanomaterial aggregation and to promote homogenous size distribution. The selected reactor consists of a mixer stage aided by ultrasound waves and a reaction stage using a N2-liquid segmented flow to prevent magnetite oxidation to non-magnetic phases. A milli-fluidic reactor was developed to increase the production rate where a magnetite throughput close to 450 mg/h in a continuous fashion was obtained.

Keywords: continuous production, magnetic nanoparticles, microfluidics, nanomaterials

Procedia PDF Downloads 582
5397 Development and Evaluation of Simvastatin Based Self Nanoemulsifying Drug Delivery System (SNEDDS) for Treatment of Alzheimer's Disease

Authors: Hardeep

Abstract:

The aim of this research work to improve the solubility and bioavailability of Simvastatin using a self nanoemulsifying drug delivery system (SNEDDS). Self emulsifying property of various oils including essential oils was evaluated with suitable surfactants and co-surfactants. Validation of a method for accuracy, repeatability, Interday and intraday precision, ruggedness, and robustness were within acceptable limits. The liquid SNEDDS was prepared and optimized using a ternary phase diagram, thermodynamic, centrifugation and cloud point studies. The globule size of optimized formulations was less than 200 nm which could be an acceptable nanoemulsion size range. The mean droplet size, drug loading, PDI and zeta potential were found to be 141.0 nm, 92.22%, 0.23 and -10.13 mV and 153.5nm, 93.89 % ,0.41 and -11.7 mV and 164.26 nm, 95.26% , 0.41 and -10.66mV respectively.

Keywords: simvastatin, self nanoemulsifying drug delivery system, solubility, bioavailability

Procedia PDF Downloads 191
5396 The Adaptive Properties of the Strategic Assurance System of the National Economy Sustainability to the Economic Security Threats

Authors: Badri Gechbaia

Abstract:

Adaptive management as a fundamental element of the concept of the assurance of economy`s sustainability to the economic security of the system-synergetic type has been considered. It has been proved that the adaptive sustainable development is a transitional phase from the extensive one and later on from the rapid growth to the sustainable development. It has been determined that the adaptive system of the strategic assurance of the sustainability of the economy to the economic security threats is formed on the principles of the domination in its complex of the subsystems with weightier adaptive characteristics that negate the destructive influence of external and internal environmental factors on the sustainability of the national economy.

Keywords: adaptive management, adaptive properties, economic security, strategic assurance

Procedia PDF Downloads 498
5395 An Optimization Tool-Based Design Strategy Applied to Divide-by-2 Circuits with Unbalanced Loads

Authors: Agord M. Pinto Jr., Yuzo Iano, Leandro T. Manera, Raphael R. N. Souza

Abstract:

This paper describes an optimization tool-based design strategy for a Current Mode Logic CML divide-by-2 circuit. Representing a building block for output frequency generation in a RFID protocol based-frequency synthesizer, the circuit was designed to minimize the power consumption for driving of multiple loads with unbalancing (at transceiver level). Implemented with XFAB XC08 180 nm technology, the circuit was optimized through MunEDA WiCkeD tool at Cadence Virtuoso Analog Design Environment ADE.

Keywords: divide-by-2 circuit, CMOS technology, PLL phase locked-loop, optimization tool, CML current mode logic, RF transceiver

Procedia PDF Downloads 458
5394 Graphene Oxide Fiber with Different Exfoliation Time and Activated Carbon Particle

Authors: Nuray Uçar, Mervin Ölmez, Özge Alptoğa, Nilgün K. Yavuz, Ayşen Önen

Abstract:

In recent years, research on continuous graphene oxide fibers has been intensified. Therefore, many factors of production stages are being studied. In this study, the effect of exfoliation time and presence of activated carbon particle (ACP) on graphene oxide fiber’s properties has been analyzed. It has been seen that cross-sectional appearance of sample with ACP is harsh and porous because of ACP. The addition of ACP did not change the electrical conductivity. However, ACP results in an enormous decrease of mechanical properties. Longer exfoliation time results to higher crystallinity degree, C/O ratio and less d space between layers. The breaking strength and electrical conductivity of sample with less exfoliation time is some higher than sample with high exfoliation time.

Keywords: activated carbon, coagulation by wet spinning, exfoliation, graphene oxide fiber

Procedia PDF Downloads 334
5393 Medial Temporal Tau Predicts Memory Decline in Cognitively Unimpaired Elderly

Authors: Angela T. H. Kwan, Saman Arfaie, Joseph Therriault, Zahra Azizi, Firoza Z. Lussier, Cecile Tissot, Mira Chamoun, Gleb Bezgin, Stijn Servaes, Jenna Stevenon, Nesrine Rahmouni, Vanessa Pallen, Serge Gauthier, Pedro Rosa-Neto

Abstract:

Alzheimer’s disease (AD) can be detected in living people using in vivo biomarkers of amyloid-β (Aβ) and tau, even in the absence of cognitive impairment during the preclinical phase. [¹⁸F]-MK-6420 is a high affinity positron emission tomography (PET) tracer that quantifies tau neurofibrillary tangles, but its ability to predict cognitive changes associated with early AD symptoms, such as memory decline, is unclear. Here, we assess the prognostic accuracy of baseline [18F]-MK-6420 tau PET for predicting longitudinal memory decline in asymptomatic elderly individuals. In a longitudinal observational study, we evaluated a cohort of cognitively normal elderly participants (n = 111) from the Translational Biomarkers in Aging and Dementia (TRIAD) study (data collected between October 2017 and July 2020, with a follow-up period of 12 months). All participants underwent tau PET with [¹⁸F]-MK-6420 and Aβ PET with [¹⁸F]-AZD-4694. The exclusion criteria included the presence of head trauma, stroke, or other neurological disorders. There were 111 eligible participants who were chosen based on the availability of Aβ PET, tau PET, magnetic resonance imaging (MRI), and APOEε4 genotyping. Among these participants, the mean (SD) age was 70.1 (8.6) years; 20 (18%) were tau PET positive, and 71 of 111 (63.9%) were women. A significant association between baseline Braak I-II [¹⁸F]-MK-6240 SUVR positivity and change in composite memory score was observed at the 12-month follow-up, after correcting for age, sex, and years of education (Logical Memory and RAVLT, standardized beta = -0.52 (-0.82-0.21), p < 0.001, for dichotomized tau PET and -1.22 (-1.84-(-0.61)), p < 0.0001, for continuous tau PET). Moderate cognitive decline was observed for A+T+ over the follow-up period, whereas no significant change was observed for A-T+, A+T-, and A-T-, though it should be noted that the A-T+ group was small.Our results indicate that baseline tau neurofibrillary tangle pathology is associated with longitudinal changes in memory function, supporting the use of [¹⁸F]-MK-6420 PET to predict the likelihood of asymptomatic elderly individuals experiencing future memory decline. Overall, [¹⁸F]-MK-6420 PET is a promising tool for predicting memory decline in older adults without cognitive impairment at baseline. This is of critical relevance as the field is shifting towards a biological model of AD defined by the aggregation of pathologic tau. Therefore, early detection of tau pathology using [¹⁸F]-MK-6420 PET provides us with the hope that living patients with AD may be diagnosed during the preclinical phase before it is too late.

Keywords: alzheimer’s disease, braak I-II, in vivo biomarkers, memory, PET, tau

Procedia PDF Downloads 70
5392 Reactors with Effective Mixing as a Solutions for Micro-Biogas Plant

Authors: M. Zielinski, M. Debowski, P. Rusanowska, A. Glowacka-Gil, M. Zielinska, A. Cydzik-Kwiatkowska, J. Kazimierowicz

Abstract:

Technologies for the micro-biogas plant with heating and mixing systems are presented as a part of the Research Coordination for a Low-Cost Biomethane Production at Small and Medium Scale Applications (Record Biomap). The main objective of the Record Biomap project is to build a network of operators and scientific institutions interested in cooperation and the development of promising technologies in the sector of small and medium-sized biogas plants. The activities carried out in the project will bridge the gap between research and market and reduce the time of implementation of new, efficient technological and technical solutions. Reactor with simultaneously mixing and heating system is a concrete tank with a rectangular cross-section. In the reactor, heating is integrated with the mixing of substrate and anaerobic sludge. This reactor is solution dedicated for substrates with high solids content, which cannot be introduced to the reactor with pumps, even with positive displacement pumps. Substrates are poured to the reactor and then with a screw pump, they are mixed with anaerobic sludge. The pumped sludge, flowing through the screw pump, is simultaneously heated by a heat exchanger. The level of the fermentation sludge inside the reactor chamber is above the bottom edge of the cover. Cover of the reactor is equipped with the screw pump driver. Inside the reactor, an electric motor is installed that is driving a screw pump. The heated sludge circulates in the digester. The post-fermented sludge is collected using a drain well. The inlet to the drain well is below the level of the sludge in the digester. The biogas is discharged from the reactor by the biogas intake valve located on the cover. The technology is very useful for fermentation of lignocellulosic biomass and substrates with high content of dry mass (organic wastes). The other technology is a reactor for micro-biogas plant with a pressure mixing system. The reactor has a form of plastic or concrete tank with a circular cross-section. The effective mixing of sludge is ensured by profiled at 90° bottom of the tank. Substrates for fermentation are supplied by an inlet well. The inlet well is equipped with a cover that eliminates odour release. The introduction of a new portion of substrates is preceded by pumping of digestate to the disposal well. Optionally, digestate can gravitationally flow to digestate storage tank. The obtained biogas is discharged into the separator. The valve supplies biogas to the blower. The blower presses the biogas from the fermentation chamber in such a way as to facilitate the introduction of a new portion of substrates. Biogas is discharged from the reactor by valve that enables biogas removal but prevents suction from outside the reactor.

Keywords: biogas, digestion, heating system, mixing system

Procedia PDF Downloads 143
5391 Facies Analysis and Depositional Environment of the Late Carboniferous (Stephanian) Souss Basin, Morocco

Authors: Abouchouaib Belahmira, Joerg W. Schneider, Hafid Saber, Sara Akboub

Abstract:

The lithofacies analyzed herein were reported from the interbedded fluvial and lacustrine deposits of the Oued Issene and El Menizla formations. These formations are part of the sedimentary fill of the Carboniferous (Stephanian) submontaneous Souss basin. The latter is situated in the western High Atlas Mountains, south-central Morocco, about 50km east of Agadir. The Souss basin started as a single basin but was separated into sub-basins called Ida Ou Zal and Ida Ou Ziki by sinistral displacement along the west branch of the Tizi N'Test Fault during the end of the Mauritanid phase of the Variscan orogeny in Morocco, after the early Stephanian (Kasimovian) and before the late middle Permian (Capitanian). The studied succession is a monotonous finning-upward sequence of 1800 m thick. It consists of fine-grained sandstone, finely bedded siltstone and thinly laminated claystone, and black shale. Herein we provide a detailed characterization of lithofacies of the upper El Menizla and Oued Issène formations, with a focus on the prevailing overbank to flood plain fine-grained lithofacies. The studied facies are capping the Stephanian alluvial fan basal clast-supported conglomerates that are intercalated bedded coarse-grained sandstones of Ikhourba Formation in the Ou Zal subbasin and Tajgaline Formation in the Ida Ou Ziki subbasin, respectively. Within the fluvial elements, only two main facies have been observed. It comprises channel-fill and channel-bar deposits, mostly occur as lenticular –shape sand bodies or sheet-like sand greenish to gray fine-to medium (Fm), massive internally structureless, or very locally exhibits a medium to large scale trough-cross bedding medium to coarse sandstone (St), observable in relatively thicker bed. These facies are laterally extensive, with a thickness varying from a few to several meters. Finer-grained sediments such as mud can be present as drapes over bedforms. Whilst the fluvial association FA1, the overbank elements are represented by a relatively wide range of 5 facies. This exhibit mostly a cm scale horizontally bedded greenish fine- to medium sand and silt, and mm scale fossiliferous thinly laminated dark gray- black Corganic-rich clays to siltstone associated with black shale. Thus, FA2 includes flood plain fines (Fh, R) associated with the paleosols and back swamp coaly clay facies (C). The floodplain lake element comprises only laminated organic-rich dark gray facies of claystone, black shale, and graded siltstone. Bedsets are dm to several meters thick (typically < 1 m thick). They are intercalated between several m-thick fluvial sandstone, extend over a few meters, and are poorly bioturbated. The lacustrine facies described in this study have been divided into two sub-facies (Fl, B) based on field observations that indicate differing environmental conditions of formation. Thus, the thorough analysis of the lithofacies of the Souss basin units allows us to reconstruct the original environment that was interpreted as a typical fluvial-dominated braided to anastomosing wide distributary channel system and surrounding deep to shallow freshwater floodplain lakes and back swamps.

Keywords: Souss, carboniferous, facies, depositional setting

Procedia PDF Downloads 89
5390 Synthesis of Pendent Compartmental Ligand Derived from Polymethacrylate of 3-Formylsalicylic Acid Schiff Base and Its Application Studies

Authors: Dhivya Arumugam, Kaliyappan Thananjeyan

Abstract:

The monomer of (3-((4-(methacryloyloxy)phenylimino)methyl)-2-hydroxybenzoic acid) schiff base polymer was prepared by reacting methacryloyl chloride with imine compound derived from 3-formylsalisylic acid and 4- aminophenol. The monomer was polymerized in DMF at 70oC using benzoyl peroxide as free radical initiator. Polymer metal complex was obtained in DMF solution of polymer with aqueous solution of metal ions. The polymer and the polymer metal complex were characterized by elemental analysis and spectral studies. The elemental analysis data suggest that the metal to ligand ratio is 1:1 and hence, it acts as a binucleating compartmental ligand. The IR spectral data of these complexes suggest that the metals are coordinated through nitrogen of the imine group, the oxygen of carboxylate ion and the oxygen of the phenolic –OH group which also acts as the bridging ligand. The electronic spectra and magnetic moments of the polychelates shows that octahedral and square planar structure for Ni(II) and Cu(II) complexes respectively. X-ray diffraction studies revealed that polychelates are highly crystalline. The thermal and electrical properties, catalytic activity, structure property relationships are discussed. Further the synthesized polymer was used for metal uptake studies from waste water, which is one of the effective waste water treatment strategies. And also, the polymers and polychelates were investigated for antimicrobial activity with various microorganisms by using agar well diffusion method and the results have been discussed.

Keywords: acyclic compartmental ligands, binucleating ligand, 3-formylsalicylic acid, free radical polymerization, polluting ions, polychelate

Procedia PDF Downloads 114
5389 Influence of Rainfall Intensity on Infiltration and Deformation of Unsaturated Soil Slopes

Authors: Bouziane Mohamed Tewfik

Abstract:

In order to improve the understanding of the influence of rainfall intensity on infiltration and deformation behaviour of unsaturated soil slopes, numerical 2D analyses are carried out by a three phase elasto-viscoplastic seepage-deformation coupled method. From the numerical results, it is shown that regardless of the saturated permeability of the soil slope, the increase in the pore water pressure (reduction in suction) during rainfall infiltration is localized close to the slope surface. In addition, the generation of the pore water pressure and the lateral displacement are mainly controlled by the ratio of the rainfall intensity to the saturated permeability of the soil.

Keywords: unsaturated soil, slope stability, rainfall infiltration, numerical analysis

Procedia PDF Downloads 461
5388 Inertial Spreading of Drop on Porous Surfaces

Authors: Shilpa Sahoo, Michel Louge, Anthony Reeves, Olivier Desjardins, Susan Daniel, Sadik Omowunmi

Abstract:

The microgravity on the International Space Station (ISS) was exploited to study the imbibition of water into a network of hydrophilic cylindrical capillaries on time and length scales long enough to observe details hitherto inaccessible under Earth gravity. When a drop touches a porous medium, it spreads as if laid on a composite surface. The surface first behaves as a hydrophobic material, as liquid must penetrate pores filled with air. When contact is established, some of the liquid is drawn into pores by a capillarity that is resisted by viscous forces growing with length of the imbibed region. This process always begins with an inertial regime that is complicated by possible contact pinning. To study imbibition on Earth, time and distance must be shrunk to mitigate gravity-induced distortion. These small scales make it impossible to observe the inertial and pinning processes in detail. Instead, in the International Space Station (ISS), astronaut Luca Parmitano slowly extruded water spheres until they touched any of nine capillary plates. The 12mm diameter droplets were large enough for high-speed GX1050C video cameras on top and side to visualize details near individual capillaries, and long enough to observe dynamics of the entire imbibition process. To investigate the role of contact pinning, a text matrix was produced which consisted nine kinds of porous capillary plates made of gold-coated brass treated with Self-Assembled Monolayers (SAM) that fixed advancing and receding contact angles to known values. In the ISS, long-term microgravity allowed unambiguous observations of the role of contact line pinning during the inertial phase of imbibition. The high-speed videos of spreading and imbibition on the porous plates were analyzed using computer vision software to calculate the radius of the droplet contact patch with the plate and height of the droplet vs time. These observations are compared with numerical simulations and with data that we obtained at the ESA ZARM free-fall tower in Bremen with a unique mechanism producing relatively large water spheres and similarity in the results were observed. The data obtained from the ISS can be used as a benchmark for further numerical simulations in the field.

Keywords: droplet imbibition, hydrophilic surface, inertial phase, porous medium

Procedia PDF Downloads 125
5387 Phase-Averaged Analysis of Three-Dimensional Vorticity in the Wake of Two Yawed Side-By-Side Circular Cylinders

Authors: T. Zhou, S. F. Mohd Razali, Y. Zhou, H. Wang, L. Cheng

Abstract:

The wake flow behind two yawed side-by-side circular cylinders is investigated using a three-dimensional vorticity probe. Four yaw angles (α), namely, 0°, 15°, 30° and 45° and two cylinder spacing ratios T* of 1.7 and 3.0 were tested. For T* = 3.0, there exist two vortex streets and the cylinders behave as independent and isolated ones. The maximum contour value of the coherent stream-wise vorticity is only about 10% of that of the spanwise vorticity. With the increase of α, increases whereas decreases. At α = 45°, is about 67% of. For T* = 1.7, only a single peak is detected in the energy spectrum. The span-wise vorticity contours have an organized pattern only at α = 0°. The maximum coherent vorticity contours of and for T* = 1.7 are about 30% and 7% of those for T* = 3.0. The independence principle (IP) in terms of Strouhal numbers is applicable in both wakes when α< 40°.

Keywords: circular cylinder wake, vorticity, vortex shedding, side-by-side

Procedia PDF Downloads 330
5386 Dissolution Kinetics of Chevreul’s Salt in Ammonium Cloride Solutions

Authors: Mustafa Sertçelik, Turan Çalban, Hacali Necefoğlu, Sabri Çolak

Abstract:

In this study, Chevreul’s salt solubility and its dissolution kinetics in ammonium chloride solutions were investigated. Chevreul’s salt that we used in the studies was obtained by using the optimum conditions (ammonium sulphide concentration; 0,4 M, copper sulphate concentration; 0,25 M, temperature; 60°C, stirring speed; 600 rev/min, pH; 4 and reaction time; 15 mins) determined by T. Çalban et al. Chevreul’s salt solubility in ammonium chloride solutions and the kinetics of dissolution were investigated. The selected parameters that affect solubility were reaction temperature, concentration of ammonium chloride, stirring speed, and solid/liquid ratio. Correlation of experimental results had been achieved using linear regression implemented in the statistical package program statistica. The effect of parameters on Chevreul’s salt solubility was examined and integrated rate expression of dissolution rate was found using kinetic models in solid-liquid heterogeneous reactions. The results revealed that the dissolution rate of Chevreul’s salt was decreasing while temperature, concentration of ammonium chloride and stirring speed were increasing. On the other hand, dissolution rate was found to be decreasing with the increase of solid/liquid ratio. Based on result of the applications of the obtained experimental results to the kinetic models, we can deduce that Chevreul’s salt dissolution rate is controlled by diffusion through the ash (or product layer). Activation energy of the reaction of dissolution was found as 74.83 kJ/mol. The integrated rate expression along with the effects of parameters on Chevreul's salt solubility was found to be as follows: 1-3(1-X)2/3+2(1-X)= [2,96.1013.(CA)3,08 .(S/L)-038.(W)1,23 e-9001,2/T].t

Keywords: Chevreul's salt, copper, ammonium chloride, ammonium sulphide, dissolution kinetics

Procedia PDF Downloads 300
5385 Lateral Torsional Buckling of an Eccentrically Loaded Channel Section Beam

Authors: L. Dahmani, S. Drizi, M. Djemai, A. Boudjemia, M. O. Mechiche

Abstract:

Channel sections are widely used in practice as beams. However, design rules for eccentrically loaded (not through shear center) beams with channel cross- sections are not available in Eurocode 3. This paper compares the ultimate loads based on the adjusted design rules for lateral torsional buckling of eccentrically loaded channel beams in bending to the ultimate loads obtained with Finite Element (FE) simulations on the basis of a parameter study. Based on the proposed design rule, this study has led to a new design rule which conforms to Eurocode 3.

Keywords: ANSYS, Eurocode 3, finite element method, lateral torsional buckling, steel channel beam

Procedia PDF Downloads 383
5384 Landmines and the Postcolonial Security Discourse in Zimbabwe

Authors: Fradreck Jockonia Mujuru

Abstract:

The effects of landmine residues from the Zimbabwean liberation war are persisting. Landmines are violently maiming and killing people and animals, causing certain areas inaccessible for agriculture and habitation, instilling fear, and even inducing forced migration. A significant gap in landmines literature is that they are mainly treated as a humanitarian issue and less scholarly. This paper engaged in theorising landmines using postcolonial literature as an epistemology. The results exhibit three issues. One, postcolonial literature provides a timeframe, a process, a space, and an attitude towards modernity on the inquiry of landmines. Two, landmines are understood in the context of war and were further decolonised to pick unique principles studied. Lastly, some of the unique principles found in landmines after decolonising are their ability to provide surveillance, repression and violent fate to all who cross the set boundaries. Therefore, theorising landmines can also be pushed further to be understood through repression. This article concluded that landmines can be theorised outside mainstream International Relations theories using postcolonial literature.

Keywords: landmines, postcolonial, repression, security, violence

Procedia PDF Downloads 67
5383 The Establishment of Probabilistic Risk Assessment Analysis Methodology for Dry Storage Concrete Casks Using SAPHIRE 8

Authors: J. R. Wang, W. Y. Cheng, J. S. Yeh, S. W. Chen, Y. M. Ferng, J. H. Yang, W. S. Hsu, C. Shih

Abstract:

To understand the risk for dry storage concrete casks in the cask loading, transfer, and storage phase, the purpose of this research is to establish the probabilistic risk assessment (PRA) analysis methodology for dry storage concrete casks by using SAPHIRE 8 code. This analysis methodology is used to perform the study of Taiwan nuclear power plants (NPPs) dry storage system. The process of research has three steps. First, the data of the concrete casks and Taiwan NPPs are collected. Second, the PRA analysis methodology is developed by using SAPHIRE 8. Third, the PRA analysis is performed by using this methodology. According to the analysis results, the maximum risk is the multipurpose canister (MPC) drop case.

Keywords: PRA, dry storage, concrete cask, SAPHIRE

Procedia PDF Downloads 207
5382 Thematic Analysis of Ramayana Narrative Scroll Paintings: A Need for Knowledge Preservation

Authors: Shatarupa Thakurta Roy

Abstract:

Along the limelight of mainstream academic practices in Indian art, exist a significant lot of habitual art practices that are mutually susceptible in their contemporary forms. Narrative folk paintings of regional India has successfully dispersed to its audience social messages through pulsating pictures and orations. The paper consists of images from narrative scroll paintings on ‘Ramayana’ theme from various neighboring states as well as districts in India, describing their subtle differences in style of execution, method, and use of material. Despite sharing commonness in the choice of subject matter, habitual and ceremonial Indian folk art in its formative phase thrived within isolated locations to yield in remarkable variety in the art styles. The differences in style took place district wise, cast wise and even gender wise. An open flow is only evident in the contemporary expressions as a result of substantial changes in social structures, mode of communicative devices, cross-cultural exposures and multimedia interactivities. To decipher the complex nature of popular cultural taste of contemporary India it is important to categorically identify its root in vernacular symbolism. The realization of modernity through European primitivism was rather elevated as a perplexed identity in Indian cultural margin in the light of nationalist and postcolonial ideology. To trace the guiding factor that has still managed to obtain ‘Indianness’ in today’s Indian art, researchers need evidences from the past that are yet to be listed in most instances. They are commonly created on ephemeral foundations. The artworks are also found in endangered state and hence, not counted much friendly for frequent handling. The museums are in dearth of proper technological guidelines to preserve them. Even though restoration activities are emerging in the country, the existing withered and damaged artworks are in threat to perish. An immediacy of digital achieving is therefore envisioned as an alternative to save this cultural legacy. The method of this study is, two folded. It primarily justifies the richness of the evidences by conducting categorical aesthetic analysis. The study is supported by comments on the stylistic variants, thematic aspects, and iconographic identities alongside its anthropological and anthropomorphic significance. Further, it explores the possible ways of cultural preservation to ensure cultural sustainability that includes technological intervention in the form of digital transformation as an altered paradigm for better accessibility to the available recourses. The study duly emphasizes on visual description in order to culturally interpret and judge the rare visual evidences following Feldman’s four-stepped method of formal analysis combined with thematic explanation. A habitual design that emerges and thrives within complex social circumstances may experience change placing its principle philosophy at risk by shuffling and altering with time. A tradition that respires in the modern setup struggles to maintain timeless values that operate its creative flow. Thus, the paper hypothesizes the survival and further growth of this practice within the dynamics of time and concludes in realization of the urgency to transform the implicitness of its knowledge into explicit records.

Keywords: aesthetic, identity, implicitness, paradigm

Procedia PDF Downloads 358
5381 Electrochemical Synthesis and Morphostructural Study of the Cuprite Thin Film

Authors: M. El Hajji, A. Hallaoui, L. Bazzi, A. Benlhachemi, Lh. Bazzi, M. Hilali, O. Jbara, A. Tara, B. Bakiz

Abstract:

The cathodic electro deposition of the cuprite Cu2O by chrono potentiometry is performed on two types of electrodes "titanium and stainless steel", in a basic medium containing the precursor of copper. The plot produced vs SCE, shows the formation of a brown layer on the electrode surface. The chrono potentiometric recording made between - 0.2 and - 1 mA/cm2, has allowed us to have a deposit having different morphologies and structural orientation obtained as a function of the variation of many parameters. The morphology, the size of crystals, and the phase of the deposits produced were studied by conventional techniques of analysis of the solid, particularly the X-ray diffraction (XRD), scanning electron microscopy analysis (SEM) and quantitative chemical analysis (EDS). The results will be presented and discussed, they show that the majority of deposits are pure and uniform.

Keywords: cathodic electrodeposition, cuprite Cu2O, XRD, SEM, EDS analysis

Procedia PDF Downloads 416
5380 The Relationship between Ruins and Vegetation: Different Approaches during the Centuries and within the Various Disciplinary Fields, Investigation of Writings and Projects

Authors: Rossana Mancini

Abstract:

The charm of a ruin colonised by wild plants and flowers is part of Western culture. The relationship between ruins and vegetation involves a wide range of different fields of research. During the first phase of the research the most important writings and projects about this argument were investigated, to understand how the perception of the co-existence of ruins and vegetation has changed over time and to investigate the various different approaches that these different fields have adopted when tackling this issue. The paper presents some practical examples of projects carried out from the early 1900s on. The major result is that specifically regards conservation, the best attitude is the management of change, an inevitable process when it comes to the co-existence of ruins and nature and, particularly, ruins and vegetation. Limiting ourselves to adopting measures designed to stop, or rather slow down, the increasing level of entropy (and therefore disorder) may not be enough.

Keywords: ruins, vegetation, conservation, archaeology, architecture

Procedia PDF Downloads 320
5379 Real-Time Classification of Marbles with Decision-Tree Method

Authors: K. S. Parlak, E. Turan

Abstract:

The separation of marbles according to the pattern quality is a process made according to expert decision. The classification phase is the most critical part in terms of economic value. In this study, a self-learning system is proposed which performs the classification of marbles quickly and with high success. This system performs ten feature extraction by taking ten marble images from the camera. The marbles are classified by decision tree method using the obtained properties. The user forms the training set by training the system at the marble classification stage. The system evolves itself in every marble image that is classified. The aim of the proposed system is to minimize the error caused by the person performing the classification and achieve it quickly.

Keywords: decision tree, feature extraction, k-means clustering, marble classification

Procedia PDF Downloads 377
5378 Unravelling the Impact of Job Resources: Alleviating Job-Related Anxiety to Forster Employee Creativity Within the Oil and Gas Industry

Authors: Nana Kojo Ayimadu Baafi, Kwesi Amponsah-Tawiah

Abstract:

The study investigated the relationship between job-related anxiety and employee creativity. The study further explored the role of job resources in moderating the relationship between job-related anxiety and employee creativity within the oil and gas industries. The study utilized a cross-sectional survey design. A non-probability sampling technique, specifically convenience sampling, was used to sample 1200 participants from multiple companies within the oil and gas industries. The collected data were analyzed using Regression analysis and PROCESS macro for the moderation analysis. The study empirically demonstrated a negative significant relationship between job-related anxiety and employee creativity. It also exhibited that job resources moderated the relationship between job-related anxiety and creativity. This study addresses gaps in previous studies by highlighting the significance of job resources in how job-related anxiety affects employee creativity.

Keywords: employee creativity, job-related anxiety, job resource, human resources

Procedia PDF Downloads 37
5377 Spectral Broadening in an InGaAsP Optical Waveguide with χ(3) Nonlinearity Including Two Photon Absorption

Authors: Keigo Matsuura, Isao Tomita

Abstract:

We have studied a method to widen the spectrum of optical pulses that pass through an InGaAsP waveguide for application to broadband optical communication. In particular, we have investigated the competitive effect between spectral broadening arising from nonlinear refraction (optical Kerr effect) and shrinking due to two photon absorption in the InGaAsP waveguide with chi^(3) nonlinearity. The shrunk spectrum recovers broadening by the enhancement effect of the nonlinear refractive index near the bandgap of InGaAsP with a bandgap wavelength of 1490 nm. The broadened spectral width at around 1525 nm (196.7 THz) becomes 10.7 times wider than that at around 1560 nm (192.3 THz) without the enhancement effect, where amplified optical pulses with a pulse width of 2 ps and a peak power of 10 W propagate through a 1-cm-long InGaAsP waveguide with a cross-section of 4 um^2.

Keywords: InGaAsP waveguide, Chi^(3) nonlinearity, spectral broadening, photon absorption

Procedia PDF Downloads 629
5376 Comparative Study of Antimicrobial Activity of Bacteriocin Producing Lactic Acid Bacteria from Fermented Batter of Green Gram And Bengal Gram Against Food-Borne Pathogens

Authors: Bandi Aruna

Abstract:

The increase of multidrug-resistant pathogens and the restriction on the use of antibiotics due to its side effects have drawn attention to the search for possible alternatives. Bacteriocins are ribosomally synthesized antimicrobial peptides that are active against Gram-positive and Gram-negative bacteria. The bacteriocins from lactic acid bacteria represent an important application of these peptides as clinical drugs or as food biopreservatives. The present study describes the isolation of bacteriocin producing lactic acid bacteria (LAB) from fermented batter of green gram and bengal gram using Man, Rogosa and Sharpe (MRS) media. The bacteriocin produced by these organisms inhibited the growth of Staphylococcus aureus, Escherichia coli, Klebsiella species, Pseudomonas aeruginosa, The isolates G1, G2 were isolated from green gram; B1 and B2 were isolated from fermented bengal gram batter. G1 and G2 were identified as Lactobacillus casie and B1 and B2 were identified as Streptococcus species. Antimicrobial activity of the bacteriocin produced by these strains was studied by agar well diffusion method. Bacteriocins produced by the Lactobacillus casie and Streptococcus secies retained their antagonistic property at pH of 5 and pH of 7. Exposure of bacteriocin to UV light for 4 min showed antibacterial activity. The antagonistic property was observed even at 100°C demonstrating stability at higher temperatures of the bacteriocin. The bacteriocins were stable for a period of 15 days at 27°C. The bacteriocins of G1, G2, and B2 exhibited highest antagonistic activity at pH of 5 and B1 at pH of 7. Therefore, the bacteriocins of the isolates may find important application in controlling the food-borne pathogens.

Keywords: Keywords: Antibacterial activity, Lactic acid bacteria, Bacteriocin

Procedia PDF Downloads 395
5375 Investigation of the Fading Time Effects on Microstructure and Mechanical Properties in Vermicular Cast Iron

Authors: Mehmet Ekici

Abstract:

In this study, the fading time affecting the mechanical properties and microstructures of vermicular cast iron were studied. Pig iron and steel scrap weighing about 12 kg were charged into the high-frequency induction furnace crucible and completely melted for production of vermicular cast iron. The slag was skimmed using a common flux. After fading time was set at 1. 3 and 5 minutes. In this way, three vermicular cast iron was produced that same composition but different phase structures. The microstructure of specimens was investigated, and uni-axial tensile test and the Charpy impact test were performed, and their micro-hardness measurements were done in order to characterize the mechanical behaviours of vermicular cast iron.

Keywords: vermicular cast iron, fading time, hardness, tensile test and impact test

Procedia PDF Downloads 337
5374 The Effect of Arabic Gum on Polyethersulfone Membranes

Authors: Yehia Manawi, Viktor Kochkodan, Muataz Hussien

Abstract:

In this paper, the effect of adding Arabic Gum (AG) to the dope solutions of polyethersulfone (PES) was studied. The aim of adding AG is to enhance the properties of ultrafiltration membranes such as hydrophilicity, porosity and selectivity. several AG loading (0.1-3.0 wt.%) in PES/ N-Methyl-2-pyrrolidone (NMP) casting solutions were prepared to fabricate PES membranes using phase inversion technique. The surface morphology, hydrophilicity and selectivity of the cast PES/AG membranes were analyzed using scanning electron microscopy and contact angle measurements. The selectivity of the fabricated membranes was also tested by filtration of oil solutions (1 ppm) and found to show quite high removal efficiency. The effect of adding AG to PES membranes was found to increase the permeate flux and porosity as well as reducing surface roughness and the contact angle of the membranes.

Keywords: antifouling, Arabic gum, polyethersulfone membrane, ultrafiltration

Procedia PDF Downloads 282
5373 Environmental Performance of Different Lab Scale Chromium Removal Processes

Authors: Chiao-Cheng Huang, Pei-Te Chiueh, Ya-Hsuan Liou

Abstract:

Chromium-contaminated wastewater from electroplating industrial activity has been a long-standing environmental issue, as it can degrade surface water quality and is harmful to soil ecosystems. The traditional method of treating chromium-contaminated wastewater has been to use chemical coagulation processes. However, this method consumes large amounts of chemicals such as sulfuric acid, sodium hydroxide, and sodium bicarbonate in order to remove chromium. However, a series of new methods for treating chromium-containing wastewater have been developed. This study aimed to compare the environmental impact of four different lab scale chromium removal processes: 1.) chemical coagulation process (the most common and traditional method), in which sodium metabisulfite was used as reductant, 2.) electrochemical process using two steel sheets as electrodes, 3.) reduction by iron-copper bimetallic powder, and 4.) photocatalysis process by TiO2. Each process was run in the lab, and was able to achieve 100% removal of chromium in solution. Then a Life Cycle Assessment (LCA) study was conducted based on the experimental data obtained from four different case studies to identify the environmentally preferable alternative to treat chromium wastewater. The model used for calculating the environmental impact was TRACi, and the system scope includes the production phase and use phase of chemicals and electricity consumed by the chromium removal processes, as well as the final disposal of chromium containing sludge. The functional unit chosen in this study was the removal of 1 mg of chromium. Solution volume of each case study was adjusted to 1 L in advance and the chemicals and energy consumed were proportionally adjusted. The emissions and resources consumed were identified and characterized into 15 categories of midpoint impacts. The impact assessment results show that the human ecotoxicity category accounts for 55 % of environmental impact in Case 1, which can be attributed to the sulfuric acid used for pH adjustment. In Case 2, production of steel sheet electrodes is an energy-intensive process, thus contributed to 20 % of environmental impact. In Case 3, sodium bicarbonate is used as an anti-corrosion additive, which results mainly in 1.02E-05 Comparative Toxicity Unit (CTU) in the human toxicity category and 0.54E-05 (CTU) in acidification of air. In Case 4, electricity consumption for power supply of UV lamp gives 5.25E-05 (CTU) in human toxicity category, 1.15E-05 (kg Neq) in eutrophication. In conclusion, Case 3 and Case 4 have higher environmental impacts than Case 1 and Case 2, which can be attributed mostly to higher energy and chemical consumption, leading to high impacts in the global warming and ecotoxicity categories.

Keywords: chromium, lab scale, life cycle assessment, wastewater

Procedia PDF Downloads 258
5372 Lifelong Learning in Applied Fields (LLAF) Tempus Funded Project: Assessing Constructivist Learning Features in Higher Education Settings

Authors: Dorit Alt, Nirit Raichel

Abstract:

Educational practice is continually subjected to renewal needs, due mainly to the growing proportion of information communication technology, globalization of education, and the pursuit of quality. These types of renewal needs require developing updated instructional and assessment practices that put a premium on adaptability to the emerging requirements of present society. However, university instruction is criticized for not coping with these new challenges while continuing to exemplify the traditional instruction. In order to overcome this critical inadequacy between current educational goals and instructional methods, the LLAF consortium (including 16 members from 8 countries) is collaborating to create a curricular reform for lifelong learning (LLL) in teachers' education, health care and other applied fields. This project aims to achieve its objectives by developing, and piloting models for training students in LLL and promoting meaningful learning activities that could integrate knowledge with the personal transferable skills. LLAF has created a practical guide for teachers containing updated pedagogical strategies and assessment tools based on the constructivist approach for learning. This presentation will be limited to teachers' education only and to the contribution of a pre-pilot research aimed at providing a scale designed to measure constructivist activities in higher education learning environments. A mix-method approach was implemented in two phases to construct the scale: The first phase included a qualitative content analysis involving both deductive and inductive category applications of students' observations. The results foregrounded eight categories: knowledge construction, authenticity, multiple perspectives, prior knowledge, in-depth learning, teacher- student interaction, social interaction and cooperative dialogue. The students' descriptions of their classes were formulated as 36 items. The second phase employed structural equation modeling (SEM). The scale was submitted to 597 undergraduate students. The goodness of fit of the data to the structural model yielded sufficient fit results. This research elaborates the body of literature by adding a category of in-depth learning which emerged from the content analysis. Moreover, the theoretical category of social activity has been extended to include two distinctive factors: cooperative dialogue and social interaction. Implications of these findings for the LLAF project are discussed.

Keywords: constructivist learning, higher education, mix-methodology, lifelong learning

Procedia PDF Downloads 330