Search results for: diffusion effect
7362 The Effect of Bacteria on Mercury's Biological Removal
Authors: Nastaran Soltani
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Heavy metals such as Mercury are toxic elements that enter the environment through different ways and endanger the environment, plants, animals, and humans’ health. Microbial activities reduce the amount of heavy metals. Therefore, an effective mechanism to eliminate heavy metals in the nature and factory slops, is using bacteria living in polluted areas. Karun River in Khuzestan Province in Iran has been always polluted by heavy metals as it is located among different industries in the region. This study was performed based on the data from sampling water and sediments of four stations across the river during the four seasons of a year. The isolation of resistant bacteria was performed through enrichment and direct cultivation in a solid medium containing mercury. Various bacteria such as Pseudomonas sp., Serratia Marcescens, and E.coli were identified as mercury-resistant bacteria. The power of these bacteria to remove mercury varied from 28% to 86%, with strongest power belonging to Pseudomonas sp. isolated in spring making a good candidate to be used for mercury biological removal from factory slops.Keywords: bacteria, Karun River, mercury, biological removal, mercury-resistant
Procedia PDF Downloads 2777361 The Effect of Phase Development on Micro-Climate Change of Urban Area
Authors: Tommy Lo
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This paper presented the changes in temperature and air ventilation of an inner urban area at different development stages during 2002 to 2012 and the high-rise buildings to be built in 2018. 3D simulation models ENVI-met and Autodesk Falcon were used. The results indicated that replacement of old residence buildings or open space with high-rise buildings will increase the air temperature of inner urban area; the air temperature at the pedestrian level will increase more than that at the upper levels. The temperature of the inner street in future will get higher than that in 2002, 2008 and 2012. It is attributed that heat is trapped in the street canyons as the air permeability at the pedestrian levels is lower. High-rise buildings with massive podium will further reduce the air ventilation in that area. In addition, sufficient separations among buildings is essential in design. High-rise buildings aligned along the waterfront will obstruct the wind flowing into the inner urban area and accelerate the temperature increase both in daytime and night time.Keywords: micro-climate change, urban design, ENVI-met, construction engineering
Procedia PDF Downloads 2767360 Optimization of Media for Enhanced Fermentative Production of Mycophenolic Acid by Penicillium brevicompactum
Authors: Shraddha Digole, Swarali Hingse, Uday Annapure
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Mycophenolic acid (MPA) is an immunosuppressant; produced by Penicillium Sp. Box-Behnken statistical experimental design was employed to optimize the condition of Penicillium brevicompactum NRRL 2011 for mycophenolic acid (MPA) production. Initially optimization of various physicochemical parameters and media components was carried out using one factor at a time approach and significant factors were screened by Taguchi L-16 orthogonal array design. Taguchi design indicated that glucose, KH2PO4 and MgSO4 had significant effect on MPA production. These variables were selected for further optimization studies using Box-Behnken design. Optimised fermentation condition, glucose (60 g/L), glycine (28 g/L), L-leucine (1.5g/L), KH2PO4 (3g/L), MgSO4.7H2O (1.5g/L), increased the production of MPA from 170 mg/L to 1032.54 mg/L. Analysis of variance (ANOVA) showed a high value of coefficient of determination R2 (0.9965), indicating a good agreement between experimental and predicted values and proves validity of the statistical model.Keywords: Box-Behnken design, fermentation, mycophenolic acid, Penicillium brevicompactum
Procedia PDF Downloads 4457359 Institutional Superposition, over Management and Coastal Economic Development: Coastal Areas in China
Authors: Mingbao Chen, Mingli Zhao
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The coastal zone is the intersection of land and sea system, and also is the connecting zone of the two economic systems of land and sea. In the world, all countries attach great importance to the coastal zone management and the coastal zone economy. In China, the government has developed a number of related coastal management policies and institutional, such as marine functional zoning, main function zoning, integrated coastal zone management, to ensure the sustainable utilization of the coastal zone and promote the development of coastal economic. However, in practice, the effect is not satisfactory. This paper analyses the coastal areas of coastal zone management on coastal economic growth contribution based on coastal areas economic development data with the 2007-2015 in China, which uses the method of the evaluation index system of coastal zone management institutional efficiency. The results show that the coastal zone management institutional objectives are not clear, and the institutional has high repeatability. At the same time, over management of coastal zone leads to low economic efficiency because the government management boundary is blurred.Keywords: institutional overlap, over management, coastal zone management, coastal zone economy
Procedia PDF Downloads 3777358 Theoretical Modeling of Mechanical Properties of Eco-Friendly Composites Derived from Sugar Palm
Authors: J. Sahari, S. M. Sapuan
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Eco-friendly composites have been successfully prepared by using sugar palm tree as a sources. The effect of fibre content on mechanical properties of (SPF/SPS) biocomposites have been done and the experimentally tensile properties (tensile strength and modulus) of biocomposites have been compared with the existing theories of reinforcement. The biocomposites were prepared with different amounts of fibres (i.e. 10%, 20% and 30% by weight percent). The mechanical properties of plasticized SPS improved with the incorporation of fibres. Both approaches (experimental and theoretical) show that the young’s modulus of the biocomposites is consistently increased when the sugar palm fibre (SPF) are placed into the sugar palm starch matrix (SPS). Surface morphological study through scanning electron microscopy showed homogeneous distribution of fibres and matrix with good adhesion which play an important role in improving the mechanical properties of biocomposites. The observed deviations between the experimental and theoretical values are explained by the simplifying model assumptions applied for the configuration of the composites, in particular the sugar palm starch composites.Keywords: eco-friendly, biocomposite, mechanical, experimental, theoretical
Procedia PDF Downloads 4377357 Red Meat Price Volatility and Its' Relationship with Crude Oil and Exchange Rate
Authors: Melek Akay
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Turkey's agricultural commodity prices are prone to fluctuation but have gradually over time. A considerable amount of literature examines the changes in these prices by dealing with other commodities such as energy. Links between agricultural and energy markets have therefore been extensively investigated. Since red meat prices are becoming increasingly volatile in Turkey, this paper analyses the price volatility of veal, lamb and the relationship between red meat and crude oil, exchange rates by applying the generalize all period unconstraint volatility model, which generalises the GARCH (p, q) model for analysing weekly data covering a period of May 2006 to February 2017. Empirical results show that veal and lamb prices present volatility during the last decade, but particularly between 2009 and 2012. Moreover, oil prices have a significant effect on veal and lamb prices as well as their previous periods. Consequently, our research can lead policy makers to evaluate policy implementation in the appropriate way and reduce the impacts of oil prices by supporting producers.Keywords: red meat price, volatility, crude oil, exchange rates, GARCH models, Turkey
Procedia PDF Downloads 1197356 The Investigation of Bodily-Kinesthetic Intelligence Levels in Adolescents
Authors: Arda Ozturk, Turgay Ozgur, Mursit Aksoy, Bahar O. Ozgur, Ozan Yilmaz
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The purpose of this study was to investigate the effect of 8 weeks of basic basketball and volleyball exercises to Bodily-Kinesthetic Intelligence (BKI) levels in 245 (92 girls and 154 boys) adolescents aged between 12 and 14 years. Data collected via Bodily-Kinesthetic Intelligence scale as a subdimension of Multiple Intelligences Inventory. BKI levels were not different between basketball and volleyball groups. Statistical analyses were made based on gender, age groups (12, 13, 14 years) and exercise type. Independent samples t-test revealed that there was no significant difference between boy’s and girl’s BKI levels. One way ANOVA test revealed that there was significant difference between age group’s (12, 13, 14) BKI levels in post-test. However, Paired samples t-test revealed no significant differences between pre-post test results of adolescent’s BKI levels. In conclusion, despite the relatively long-term (8 weeks) physical activity. BKI levels have not shown significant differences.Keywords: bodily-kinesthetic intelligence, adolescent, basketball, volleyball
Procedia PDF Downloads 3847355 Effect of Capsule Storage on Viability of Lactobacillus bulgaricus and Streptococcus thermophilus in Yogurt Powder
Authors: Kanchana Sitlaothaworn
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Yogurt capsule was made by mixing 14% w/v of reconstitution of skim milk with 2% FOS. The mixture was fermented by commercial yogurt starter comprising Lactobacillus bulgaricus and Streptococcus thermophilus. These yogurts were made as yogurt powder by freeze-dried. Yogurt powder was put into capsule then stored for 28 days at 4oc. 8ml of commercial yogurt was found to be the most suitable inoculum size in yogurt production. After freeze-dried, the viability of L. bulgaricus and S. thermophilus reduced from 109 to 107 cfu/g. The precence of sucrose cannot help to protect cell from ice crystal formation in freeze-dried process, high (20%) sucrose reduced L. bulgaricus and S. thermophilus growth during fermentation of yogurt. The addition of FOS had reduced slowly the viability of both L. bulgaricus and S. thermophilus similar to control (without FOS) during 28 days of capsule storage. The viable cell exhibited satisfactory viability level in capsule storage (6.7x106cfu/g) during 21 days at 4oC.Keywords: yogurt capsule, Lactobacillus bulgaricus, Streptococcus thermophilus, freeze-drying, sucrose
Procedia PDF Downloads 3227354 Effect of Spermidine on Physicochemical Properties of Protein Based Films
Authors: Mohammed Sabbah, Prospero Di Pierro, Raffaele Porta
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Protein-based edible films and coatings have attracted an increasing interest in recent years since they might be used to protect pharmaceuticals or improve the shelf life of different food products. Among them, several plant proteins represent an abundant, inexpensive and renewable raw source. These natural biopolymers are used as film forming agents, being able to form intermolecular linkages by various interactions. However, without the addition of a plasticizing agent, many biomaterials are brittle and, consequently, very difficult to be manipulated. Plasticizers are generally small and non-volatile organic additives used to increase film extensibility and reduce its crystallinity, brittleness and water vapor permeability. Plasticizers normally act by decreasing the intermolecular forces along the polymer chains, thus reducing the relative number of polymer-polymer contacts, producing a decrease in cohesion and tensile strength and thereby increasing film flexibility allowing its deformation without rupture. The most commonly studied plasticizers are polyols, like glycerol (GLY) and some mono or oligosaccharides. In particular, GLY not only increases film extensibility but also migrates inside the film network often causing the loss of desirable mechanical properties of the material. Therefore, replacing GLY with a different plasticizer might help to improve film characteristics allowing potential industrial applications. To improve film properties, it seemed of interest to test as plasticizers some cationic small molecules like polyamines (PAs). Putrescine, spermidine (SPD), and spermine are PAs widely distributed in nature and of particular interest for their biological activities that may have some beneficial health effects. Since PAs contains amino instead of hydroxyl functional groups, they are able to trigger ionic interactions with negatively charged proteins. Bitter vetch (Vicia ervilia; BV) is an ancient grain legume crop, originated in the Mediterranean region, which can be found today in many countries around the world. This annual Vicia genus shows several favorable features, being their seeds a cheap and abundant protein source. The main objectives of this study were to investigate the effect of different concentrations of SPD on the mechanical and permeability properties of films prepared with native or heat denatured BV proteins in the presence of different concentrations of SPD and/or GLY. Therefore, a BV seed protein concentrate (BVPC), containing about 77% proteins, was used to prepare film forming solutions (FFSs), whereas GLY and SPD were added as film plasticizers, either singly or in combination, at various concentrations. Since a primary plasticizer is generally defined as a molecule that when added to a material makes it softer, more flexible and easier to be processed, our findings lead to consider SPD as a possible primary plasticizer of protein-based films. In fact, the addition of millimolar concentrations of SPD to BVPC FFS allowed obtaining handleable biomaterials with improved properties. Moreover, SPD can be also considered as a secondary plasticizer, namely an 'extender', because of its ability even to enhance the plasticizing performance of GLY. In conclusion, our studies indicate that innovative edible protein-based films and coatings can be obtained by using PAs as new plasticizers.Keywords: edible films, glycerol, plasticizers, polyamines, spermidine
Procedia PDF Downloads 1927353 2D and 3D Unsteady Simulation of the Heat Transfer in the Sample during Heat Treatment by Moving Heat Source
Authors: Zdeněk Veselý, Milan Honner, Jiří Mach
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The aim of the performed work is to establish the 2D and 3D model of direct unsteady task of sample heat treatment by moving source employing computer model on the basis of finite element method. The complex boundary condition on heat loaded sample surface is the essential feature of the task. Computer model describes heat treatment of the sample during heat source movement over the sample surface. It is started from the 2D task of sample cross section as a basic model. Possibilities of extension from 2D to 3D task are discussed. The effect of the addition of third model dimension on the temperature distribution in the sample is showed. Comparison of various model parameters on the sample temperatures is observed. Influence of heat source motion on the depth of material heat treatment is shown for several velocities of the movement. Presented computer model is prepared for the utilization in laser treatment of machine parts.Keywords: computer simulation, unsteady model, heat treatment, complex boundary condition, moving heat source
Procedia PDF Downloads 3847352 Surface Modification of Polyethylene Terephthalate Substrates via Direct Fluorination to Promote the Ag+ Ions Adsorption
Authors: Kohei Yamamoto, Jae-Ho Kim, Susumu Yonezawa
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The surface of polyethylene terephthalate (PET) was modified with fluorine gas at 25 ℃ and 100 Torr for one h. Moreover, the effect of ethanol washing on surface modification was investigated in this study. The surface roughness of the fluorinated and washed PET samples was approximately six times larger than that (0.6 nm) of the untreated thing. The results of Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy showed that the bonds such as -C=O and -C-Hx derived from raw PET decreased and were converted into fluorinated bonds such as -CFx after surface fluorination. Even after washing with ethanol, the fluorinated bonds stably existed on the surface. These fluorinated bonds showed higher electronegativity according to the zeta potential results. The negative surface charges were increased by washing the ethanol, and it caused to increase in the number of polar groups such as -CHF- and -C-Fx. The fluorinated and washed surface of PET could promote the adsorption of Ag+ ions in AgNO₃ solution because of the increased surface roughness and the negatively charged surface.Keywords: Ag+ ions adsorption, polyethylene terephthalate, surface fluorination, zeta potential
Procedia PDF Downloads 1187351 Study the Action of Malathion Induced Enzymatic Changes in the Target Organ of Fish Labeo Rohita
Authors: Sudha Summarwar, Jyotsana Pandey, Deepali Lall
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The Malathion compound has the great tendency to be accumulated in the organs of the fishes both if it is present in traces or in higher amount in the aquatic environment. It has the tendency to be accumulated more in quantity in the organs directly exposed to it. The accumulation was found to be time and concentration dependent. The accumulation of malathion was maximum in gills and is the minimum in the brain. Effect of different sub-lethal concentrations (l/5th, l/l0th, l/15th, l/20th, and 1/25th fractions of 96 hr. LC50) of malathion compound on acid phosphatase (AcPase), alkaline phosphatase (AlPase), serum glutamic oxalacetic transaminase (SGOT) and Serum Glucose-6-Phosphatase (S-G-6-Pase), serum glutamic pyruvic transaminase (SGPT) in blood of Labeo rohita exposed for the period of 15. 30, 45, and 60 days, have been studied in present investigations. In general the alterations were concentrations and duration dependent.Keywords: AcPase, AlPase, Labeo rohita, malathion, S-G-6-Pase, SGOT, SGPT
Procedia PDF Downloads 3137350 Exposure to Tactile Cues Does Not Influence Spatial Navigation in 129 S1/SvLm Mice
Authors: Rubaiyea Uddin, Rebecca Taylor, Emily Levesque
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The hippocampus, located in the limbic system, is most commonly known for its role in memory and spatial navigation (as cited in Brain Reward and Pathways). It maintains an especially important role in specifically episodic and declarative memory. The hippocampus has also recently been linked to dopamine, the reward pathway’s primary neurotransmitter. Since research has found that dopamine also contributes to memory consolidation and hippocampal plasticity, this neurotransmitter is potentially responsible for contributing to the hippocampus’s role in memory formation. In this experiment we tested to see the effect of tactile cues on spatial navigation for eight different mice. We used a radial arm that had one designated “reward” arm containing sucrose. The presence or absence of bedding was our tactile cue. We attempted to see if the memory of that cue would enhance the mice’s memory of having received the reward in that arm. The results from our study showed there was no significant response from the use of tactile cues on spatial navigation on our 129 mice. Tactile cues therefore do not influence spatial navigation.Keywords: mice, radial arm maze, memory, spatial navigation, tactile cues, hippocampus, reward, sensory skills, Alzheimer's, neuro-degenerative diseases
Procedia PDF Downloads 6837349 Activity of Some Plant Extracts on the Larvae and Eggs of Culex quinquefasciatus in the Laboratory
Authors: A. A. El Maghrbi
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The control of vectors like mosquitoes based on the application of chemical insecticides but due to its adverse effect on the environment, and development of resistance by most of species of mosquitoes including vectors of important diseases. Ethanol and acetone extracts of nine species of plants (Allium tuberosum, Apium leptophylum, Carica papaya, Cymbopogon citratus, Euphorbia cotinofolia, Melia azedarach, Ocimum canum, Ricinus common, and Tagetes erecta) were tested in respect of their influence on the eggs and larvae of Culex quinquifasciatus in concentration 100, 10 and 1 mg/L. In relation to the survival of larvae, ethanol extract of O. canum and acetone extract of A.tuberosum in 100 mg/L have larvicide activity against L4 of Cx. quinquifasciatus. For hatching of eggs, ethanol and acetone extract of A.tuberosum (100 and 10 mg/L) and acetone extract of C.citratus (100 mg/L) produced reduction in the number of eggs hatched of Cx. quinquifasciatus. Our results indicate that each extract of the plant have potential to control mosquito population and suggest that further studies are needed in this field.Keywords: Cx. quinquefasciatus, plant extract, ethanol, acetone, larvae, eggs
Procedia PDF Downloads 3577348 Influence of Cationic Surfactant (TTAB) on the Rate of Dipeptide (Gly-DL-Asp) Ninhydrin Reaction in Absence and Presence of Organic Solvents
Authors: Mohd. Akram, A. A. M. Saeed
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Surfactants are widely used in our daily life either directly in household and personal care products or indirectly in the industrial processes. The kinetics of the interaction of glycyl-DL-aspartic acid (Gly-DL-Asp) with ninhydrin has been investigated spectrophotometrically in aqueous and organic-solvent media in the absence and presence of cationic surfactant of tetradecyltrimethylammonium bromide (TTAB). The study was carried out under different experimental conditions. The first and fractional order-rate were observed for [Gly-DL-Asp] and [ninhydrin], respectively. The reaction was enhanced about four-fold by TTAB micelles. The effect of organic solvents was studied at a constant concentration of TTAB and showed an increase in the absorbance as well as the rate constant for the formation of product (Ruhemann's purple). The results obtained in micellar media are treated quantitatively in terms of pseudo-phase and Piszkiewicz cooperativity models. The Arrhenius and Eyring equations are valid for the reaction over the range of temperatures used and different activation parameters (Ea, ∆H#, ∆S#, and ∆G#) have been evaluated.Keywords: glycyl-DL-aspartic acid, ninhydrin, organic solvents, TTAB
Procedia PDF Downloads 3777347 Effect of the Diverse Standardized Patient Simulation Cultural Competence Education Strategy on Nursing Students' Transcultural Self-Efficacy Perceptions
Authors: Eda Ozkara San
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Nurse educators have been charged by several nursing organizations and accrediting bodies to provide innovative and evidence-based educational experiences, both didactic and clinical, to help students to develop the knowledge, skills, and attitudes needed to provide culturally competent nursing care to patients. Clinical simulation, which offers the opportunity for students to practice nursing skills in a risk-free, controlled environment and helps develop self-efficacy (confidence) within the nursing role. As one simulation method, the standardized patients (SPs) simulation helps educators to teach nursing students variety of skills in nursing, medicine, and other health professions. It can be a helpful tool for nurse educators to enhance cultural competence of nursing students. An alarming gap exists within the literature concerning the effectiveness of SP strategy to enhance cultural competence development of diverse student groups, who must work with patients from various backgrounds. This grant-supported, longitudinal, one-group, pretest and post-test educational intervention study aimed to examine the effect of the Diverse Standardized Patient Simulation (DSPS) cultural competence education strategy on students’ (n = 53) transcultural self-efficacy (TSE). The researcher-developed multidimensional DSPS strategy involved careful integration of transcultural nursing skills guided by the Cultural Competence and Confidence (CCC) model. As a carefully orchestrated teaching and learning strategy by specifically utilizing the SP pedagogy, the DSPS also followed international guidelines and standards for the design, implementation, evaluation, and SP training; and had content validity review. The DSPS strategy involved two simulation scenarios targeting underrepresented patient populations (Muslim immigrant woman with limited English proficiency and Irish-Italian American gay man with his partner (Puerto Rican) to be utilized in a second-semester, nine-credit, 15-week medical-surgical nursing course at an urban public US university. Five doctorally prepared content experts reviewed the DSPS strategy for content validity. The item-level content validity index (I-CVI) score was calculated between .80-1.0 on the evaluation forms. Jeffreys’ Transcultural Self-Efficacy Tool (TSET) was administered as a pretest and post-test to assess students’ changes in cognitive, practical, and affective dimensions of TSE. Results gained from this study support that the DSPS cultural competence education strategy assisted students to develop cultural competence and caused statistically significant changes (increase) in students’ TSE perceptions. Results also supported that all students, regardless of their background, benefit (and require) well designed cultural competence education strategies. The multidimensional DSPS strategy is found to be an effective way to foster nursing students’ cultural competence development. Step-by-step description of the DSPS provides an easy adaptation of this strategy with different student populations and settings.Keywords: cultural competence development, the cultural competence and confidence model, CCC model, educational intervention, transcultural self-efficacy, TSE, transcultural self-efficacy tool, TSET
Procedia PDF Downloads 1427346 Electrokinetic Transport of Power Law Fluid through Hydrophobic Micro-Slits
Authors: Ainul Haque, Ameeye Kumar Nayak
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Flow enhancement and species transport in a slit hydrophobic microchannel is studied for non-Newtonian fluids with the externally imposed electric field and pressure gradient. The incompressible Poisson-Nernst-Plank equations and the Navier-Stokes equations are approximated by lubrication theory to quantify the flow structure due to hydrophobic and hydrophilic surfaces. The analytical quantification of velocity and pressure of electroosmotic flow (EOF) is made with the numerical results due to the staggered grid based finite volume method for flow governing equations. The resistance force due to fluid friction and shear force along the surface are decreased by the hydrophobicity, enables the faster movement of fluid particles. The resulting flow enhancement factor Ef is increased with the low viscous fluid and provides maximum species transport. Also, the analytical comparison of EOF with pressure driven EOF justifies the flow enhancement due to hydrophobicity and shear impact on flow variation.Keywords: electroosmotic flow, hydrophobic surface, power-law fluid, shear effect
Procedia PDF Downloads 3717345 Directional Dependence of the Stress-Strain Behavior of Reinforced Sand
Authors: Alaa H. J. Al-Rkaby, A. Chegenizadeh, H. R. Nikraz
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The technique of reinforcing soil is an efficient, reliable and cost-effective alternative way for improving the performance of soil in civil engineering applications. Despite the anisotropic states of stresses induced within soil elements by many geotechnical structures such as footings, highways and offshore, most of the previous studies have been carried out under isotropic conditions. The anisotropic stress state in term of the inclined principal stress and the inequality of the intermediate and minor principal stresses cannot be investigated using conventional devices. Therefore, the advanced hollow cylinder apparatus, used in this work, provides a great opportunity to simulate such anisotropic stress states. To date, very little consideration has been given to how the direction of principal stress α and intermediate principal stress ratio b can affect the performance of the reinforced sand. This study presented that the anisotropic conditions of α and b resulted in significant variations in the deviator stress and volumetric strain of sand reinforced with geosynthetics. Anisotropic effect has been decreased by adding clay content.Keywords: anisotropy, reinforced sand, direction of principal stress, intermediate principal stress ratio
Procedia PDF Downloads 1897344 An Assessment of Experiential Learning Outcomes of Study Abroad Programs in Hospitality: A Learning Style Perspective
Authors: Radesh Palakurthi
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The purpose of this study was to determine the impact of experiential learning on learning outcomes in hospitality education. This paper presents the results of an online survey of students from the U.S. studying abroad and their self-reported change in learning outcomes as assessed using the Core Competencies Model for the Hospitality Industry developed by Employment and Training Development Office of the U.S. Department of Labor. The impact of student learning styles on learning outcomes is also evaluated in this study. Kolb’s Learning Styles Inventory Model was used to assess students’ learning style. The results show that students reported significant improvements in their learning outcomes because of engaging in study abroad experiential learning programs. The learning styles of the students had significant effect on one of core learning outcomes- personal effectiveness.Keywords: hospitality competencies, hospitality education, Kolb’s learning style inventory, learning outcomes, study abroad
Procedia PDF Downloads 2117343 Experimental Investigation on the Efficiency of Expanded Polystyrene Geofoam Post and Beam System in Protecting Lifelines
Authors: Masood Abdollahi, Seyed Naser Moghaddas Tafreshi
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Expanded polystyrene (EPS) geofoam is a cellular geosynthetic material that can be used to protect lifelines (e.g. pipelines, electricity cables, etc.) below ground. Post and beam system is the most recent configuration of EPS blocks which can be implemented for this purpose. It provides a void space atop lifelines which allows settlement of the loading surface with imposing no pressure on the lifelines system. This paper investigates the efficiency of the configuration of post-beam system subjected to static loading. To evaluate the soil surface settlement, beam deformation and transferred pressure over the beam, laboratory tests using two different densities for EPS blocks are conducted. The effect of geogrid-reinforcing the cover soil on system response is also investigated. The experimental results show favorable performance of EPS post and beam configuration in protecting underground lifelines.Keywords: beam deformation, EPS block, laboratory test, post-Beam system, soil surface settlement
Procedia PDF Downloads 2357342 Modeling the Impact of Time Pressure on Activity-Travel Rescheduling Heuristics
Authors: Jingsi Li, Neil S. Ferguson
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Time pressure could have an influence on the productivity, quality of decision making, and the efficiency of problem-solving. This has been mostly stemmed from cognitive research or psychological literature. However, a salient scarce discussion has been held for transport adjacent fields. It is conceivable that in many activity-travel contexts, time pressure is a potentially important factor since an excessive amount of decision time may incur the risk of late arrival to the next activity. The activity-travel rescheduling behavior is commonly explained by costs and benefits of factors such as activity engagements, personal intentions, social requirements, etc. This paper hypothesizes that an additional factor of perceived time pressure could affect travelers’ rescheduling behavior, thus leading to an impact on travel demand management. Time pressure may arise from different ways and is assumed here to be essentially incurred due to travelers planning their schedules without an expectation of unforeseen elements, e.g., transport disruption. In addition to a linear-additive utility-maximization model, the less computationally compensatory heuristic models are considered as an alternative to simulate travelers’ responses. The paper will contribute to travel behavior modeling research by investigating the following questions: how to measure the time pressure properly in an activity-travel day plan context? How do travelers reschedule their plans to cope with the time pressure? How would the importance of the activity affect travelers’ rescheduling behavior? What will the behavioral model be identified to describe the process of making activity-travel rescheduling decisions? How do these identified coping strategies affect the transport network? In this paper, a Mixed Heuristic Model (MHM) is employed to identify the presence of different choice heuristics through a latent class approach. The data about travelers’ activity-travel rescheduling behavior is collected via a web-based interactive survey where a fictitious scenario is created comprising multiple uncertain events on the activity or travel. The experiments are conducted in order to gain a real picture of activity-travel reschedule, considering the factor of time pressure. The identified behavioral models are then integrated into a multi-agent transport simulation model to investigate the effect of the rescheduling strategy on the transport network. The results show that an increased proportion of travelers use simpler, non-compensatory choice strategies instead of compensatory methods to cope with time pressure. Specifically, satisfying - one of the heuristic decision-making strategies - is adopted commonly since travelers tend to abandon the less important activities and keep the important ones. Furthermore, the importance of the activity is found to increase the weight of negative information when making trip-related decisions, especially route choices. When incorporating the identified non-compensatory decision-making heuristic models into the agent-based transport model, the simulation results imply that neglecting the effect of perceived time pressure may result in an inaccurate forecast of choice probability and overestimate the affectability to the policy changes.Keywords: activity-travel rescheduling, decision making under uncertainty, mixed heuristic model, perceived time pressure, travel demand management
Procedia PDF Downloads 1087341 Use of Fine Marble in Concrete Based On Sand Dune
Authors: M. Belachia, R. Djebien
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In the development that our country has in all areas and especially in the field of Building and Construction, the development of new building materials is a current problem where researchers are trying to find the right materials for each region and returning cheapest countries. Enhancement of crushed sand and sand dunes and reuse of waste as additions in concrete can help to overcome the deficit in aggregates. This work focuses on the development of concrete made from sand, knowing that our country has huge potential in sand dune. This study is complemented by a review of the possibility of using certain recycled wastes in concrete sand, including the effect of fines (marble powders) on the rheological and mechanical properties of concrete and sand to the outcome optimal formulation. After the characterization phase of basic materials, we proceeded to carry out the experimental program was to search the optimum characteristics by adding different percentages of fines. The aim is to show that the possibility of using local materials (sand dune) for the manufacture of concrete and reuse of waste (marble powders) in the implementation of concrete.Keywords: sand dune, mechanical properties, rheological properties, fine marble
Procedia PDF Downloads 4587340 Fabrication and Properties of Al2O3/Si Quantum Well-Structured Silicon Solar Cells
Authors: Kwang-Ho Kim, Kwan-Hong Min, Pyungwoo Jang, Chisup Jung, Kyu Seomoon
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By restricting the dimensions of silicon to less than Bohr radius of bulk crystalline silicon (∼5 nm), quantum confinement causes its effective bandgap to increase. Therefore, silicon quantum wells (QWs) using these quantum phenomena could be a good candidate to achieve high performance silicon solar cells. The Al2O3/Si QW structures were fabricated by using the successive deposition technique, as a quantum confinement device to increase the effective energy bandgap and passivation effect in Si surface for the 3rd generation solar cell applications. In Si/Al2O3 QWs, the thicknesses of Si layers and Al2O3 layers were varied between 1 to 5 nm, respectively. The roughness of deposited Si on Al2O3 was less than 4 Å in the thickness of 2 nm. By using the Al2O3/Si QW structures on Si surfaces, the lifetime measured by u-PCD technique increased as a result of passivated surface effects. The discussion about the other properties such as electrical and optical properties of the QWs structures as well as the fabricated solar cells will be presented in this paper.Keywords: Al2O3/Si quantum well, quantum confinement, solar cells, third generation, successive deposition technique
Procedia PDF Downloads 3337339 Study of Effect of Steering Column Orientation and Operator Platform Position on the Hand Vibration in Compactors
Authors: Sunil Bandaru, Suresh Yv, Srinivas Vanapalli
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Heavy machinery especially compactors has more vibrations induced from the compactor mechanism than the engines. Since the operator’s comfort is most important in any of the machines, this paper shows interest in studying the vibrations on the steering wheel for a double drum compactor. As there are no standard procedures available for testing vibrations on the steering wheel of double drum compactors, this paper tries to evaluate the vibrations on the steering wheel by considering most of the possibilities. In addition to the feasibility for the operator to adjust the steering wheel tilt as in the case of automotive, there is an option for the operator to change the orientation of the operator platform for the complete view of the road’s edge on both the ends of the front and rear drums. When the orientation is either +/-180°, the operator will be closer to the compactor mechanism; also there is a possibility for the shuffle in the modes with respect to the operator. Hence it is mandatory to evaluate the vibrations levels in both cases. This paper attempts to evaluate the vibrations on the steering wheel by considering the two operator platform positions and three steering wheel tilting angles.Keywords: FEA, CAE, steering column, steering column orientation position
Procedia PDF Downloads 2207338 Investigation of Roll-Off Factor in Pulse Shaping Filter on Maximal Ratio Combining for CDMA 2000 System
Authors: G. S. Walia, H. P. Singh, D. Padma
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The integration of wide variety of communication services is made possible with invention of 3G technology. Code Division Multiple Access 2000 operates on various RF channel bandwidths 1.2288 or 3.6864 Mcps (1x or 3x systems). It is a 3G system which offers high bandwidth and wireless broadband services but its efficiency is lowered due to various factors like fading, interference, scattering, absorption etc. This paper investigates the effect of diversity (MRC), roll off factor in Root Raised Cosine (RRC) filter for the BPSK and QPSK modulation schemes. It is possible to transmit data with minimum Inter symbol Interference and within limited bandwidth with proper pulse shaping technique. Bit error rate (BER) performance is analyzed by applying diversity technique by varying the roll off factor for BPSK and QPSK. Roll off factor reduces the ISI and diversity reduces the Fading.Keywords: CDMA2000, root raised cosine, roll-off factor, ISI, diversity, interference, fading
Procedia PDF Downloads 4007337 Effect of Urbanization on Basic Environmental Components
Authors: Sehba Saleem
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A country with a spread of only 2.4 percent of the total land surface area of the world, India is home to 17.5 percent of the world population. This fact is sufficient enough to delineate as well as simultaneously bringing to fore the paradox which exists between land and human population. It is evident that the relation which exists between both is an unequal one where the latter has the ability to multiply self, but the former remains constant. This unequal relation that exists has very significantly contributed to the depletion in the quality of land. This is because construction of every kind and nature has been forced on the land to assimilate the ever increasing population which has altered the not only the land but the environment which existed on the land. To get behind this alteration, it becomes imperative to delve into concepts like urbanization, ecology and their amalgam viz. urban ecology. The concept of urban ecology does not only involve study of buildings, flora, and fauna which exists in a given land space. It goes further into establishing a relation between construction on land and the consequent harm, which the same is causing to the environmental resources like air, water etc. This paper shall try cerebrating concepts of urbanization, ecology and urban ecology in the light of relation which exists between man and nature.Keywords: asymmetrical growth, environment, urbanisation, urban space
Procedia PDF Downloads 3187336 Circular Economy-Relationship of Natural Water Collection System, Afforestation and Country Park Towards Environmental Sustainability
Authors: Kwok Tak Kit
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The government and community have raised their awareness of the benefits of water reuse. Deforestation has a significant effect to climate change as it causes the drying out of the tropical rainforest and hence increases the chance of natural hazards. The loss of forests due to natural fire or human factors would be threatening the storage and supply of clean water. In this paper, we will focus on the discussion of the relationship of the natural water collection system, afforestation and country parks towards environmental sustainability and circular economy with a case study of water conservation policy and strategy in Hong Kong and Singapore for further research. The UN General Assembly launched the Water Action Decade in 2018 to mobilize action that will help to tackle the growing challenge of water scarcity through water conservation and protect and restore water-related ecosystems, including forests, wetlands, rivers, aquifers and lakes.Keywords: afforestation, environmental sustainability, water conservation, circular economy, climate change, sustainable development goal
Procedia PDF Downloads 1237335 The Effect of Ionic Liquid Anion Type on the Properties of TiO2 Particles
Authors: Marta Paszkiewicz, Justyna Łuczak, Martyna Marchelek, Adriana Zaleska-Medynska
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In recent years, photocatalytical processes have been intensively investigated for destruction of pollutants, hydrogen evolution, disinfection of water, air and surfaces, for the construction of self-cleaning materials (tiles, glass, fibres, etc.). Titanium dioxide (TiO2) is the most popular material used in heterogeneous photocatalysis due to its excellent properties, such as high stability, chemical inertness, non-toxicity and low cost. It is well known that morphology and microstructure of TiO2 significantly influence the photocatalytic activity. This characteristics as well as other physical and structural properties of photocatalysts, i.e., specific surface area or density of crystalline defects, could be controlled by preparation route. In this regard, TiO2 particles can be obtained by sol-gel, hydrothermal, sonochemical methods, chemical vapour deposition and alternatively, by ionothermal synthesis using ionic liquids (ILs). In the TiO2 particles synthesis ILs may play a role of a solvent, soft template, reagent, agent promoting reduction of the precursor or particles stabilizer during synthesis of inorganic materials. In this work, the effect of the ILs anion type on morphology and photoactivity of TiO2 is presented. The preparation of TiO2 microparticles with spherical structure was successfully achieved by solvothermal method, using tetra-tert-butyl orthotitatane (TBOT) as the precursor. The reaction process was assisted by an ionic liquids 1-butyl-3-methylimidazolium bromide [BMIM][Br], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] and 1-butyl-3-methylimidazolium haxafluorophosphate [BMIM][PF6]. Various molar ratios of all ILs to TBOT (IL:TBOT) were chosen. For comparison, reference TiO2 was prepared using the same method without IL addition. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brenauer-Emmett-Teller surface area (BET), NCHS analysis, and FTIR spectroscopy were used to characterize the surface properties of the samples. The photocatalytic activity was investigated by means of phenol photodegradation in the aqueous phase as a model pollutant, as well as formation of hydroxyl radicals based on detection of fluorescent product of coumarine hydroxylation. The analysis results showed that the TiO2 microspheres had spherical structure with the diameters ranging from 1 to 6 µm. The TEM micrographs gave a bright observation of the samples in which the particles were comprised of inter-aggregated crystals. It could be also observed that the IL-assisted TiO2 microspheres are not hollow, which provides additional information about possible formation mechanism. Application of the ILs results in rise of the photocatalytic activity as well as BET surface area of TiO2 as compared to pure TiO2. The results of the formation of 7-hydroxycoumarin indicated that the increased amount of ·OH produced at the surface of excited TiO2 for samples TiO2_ILs well correlated with more efficient degradation of phenol. NCHS analysis showed that ionic liquids remained on the TiO2 surface confirming structure directing role of that compounds.Keywords: heterogeneous photocatalysis, IL-assisted synthesis, ionic liquids, TiO2
Procedia PDF Downloads 2647334 The Redistributive Effects of Debtor Protection Laws
Authors: Hamid Boustanifar, Geraldo Cerqueiro, María Fabiana Penas
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We exploit state-level changes in the amount of personal wealth individuals can protect under Chapter 7 to analyze the causal effect of debtor protection on income inequality. We find that an increase in state exemptions significantly increases inequality by reducing income for low-income individuals and by increasing income for high-income individuals. The increase in inequality is four times larger among the self-employed than among wage earners, and it is due mainly to a growing income gap between skilled (i.e., individuals with a college degree) and unskilled entrepreneurs. We also find that the employment rate of skilled entrepreneurs significantly increases, while the employment rate of unskilled wage earners falls. Our results are consistent with a recent literature that shows that higher exemptions redistribute credit from low-wealth to high-wealth entrepreneurs, affecting the performance of their businesses.Keywords: debtor protection, credit markets, income inequality, debtor protection laws
Procedia PDF Downloads 4267333 Degumming of Eri Silk Fabric with Ionic Liquid
Authors: Shweta K. Vyas, Rakesh Musale, Sanjeev R. Shukla
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Eri silk is a non mulberry silk which is obtained without killing the silkworms and hence it is also known as Ahmisa silk. In the present study, the results on degumming of eri silk with alkaline peroxide have been compared with those obtained by using ionic liquid (IL) 1-Butyl-3-methylimidazolium chloride [BMIM]Cl. Experiments were designed to find out the optimum processing parameters for degumming of eri silk by response surface methodology. The statistical software, Design-Expert 6.0 was used for regression analysis and graphical analysis of the responses obtained by running the set of designed experiments. Analysis of variance (ANOVA) was used to estimate the statistical parameters. The polynomial equation of quadratic order was employed to fit the experimental data. The quality and model terms were evaluated by F-test. Three dimensional surface plots were prepared to study the effect of variables on different responses. The optimum conditions for IL treatment were selected from predicted combinations and the experiments were repeated under these conditions to determine the reproducibility.Keywords: silk degumming, ionic liquid, response surface methodology, ANOVA
Procedia PDF Downloads 582