Search results for: gel strength prediction
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5854

Search results for: gel strength prediction

1864 Thermal Property of Multi-Walled-Carbon-Nanotube Reinforced Epoxy Composites

Authors: Min Ye Koo, Gyo Woo Lee

Abstract:

In this study, epoxy composite specimens reinforced with multi-walled carbon nanotube filler were fabricated using shear mixer and ultra-sonication processor. The mechanical and thermal properties of the fabricated specimens were measured and evaluated. From the electron microscope images and the results from the measurements of tensile strengths, the specimens having 0.6 wt% nanotube content show better dispersion and higher strength than those of the other specimens. The Young’s moduli of the specimens increased as the contents of the nanotube filler in the matrix were increased. The specimen having a 0.6 wt% nanotube filler content showed higher thermal conductivity than that of the other specimens. While, in the measurement of thermal expansion, specimens having 0.4 and 0.6 wt% filler contents showed a lower value of thermal expansion than that of the other specimens. On the basis of the measured and evaluated properties of the composites, we believe that the simple and time-saving fabrication process used in this study was sufficient to obtain improved properties of the specimens.

Keywords: carbon nanotube filler, epoxy composite, ultra-sonication, shear mixer, mechanical property, thermal property

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1863 Synthesis, Characterization, Computational Study, Antimicrobial Evaluation, in Vivo Toxicity Study of Manganese (II) and Copper (II) Complexes with Derivative Sulfa-drug

Authors: Afaf Bouchoucha, Karima Si Larbi, Mohamed Amine Bourouaia, Salah.Boulanouar, Safia.Djabbar

Abstract:

The synthesis, characterization and comparative biological study of manganese (II) and copper (II) complexes with an heterocyclic ligand used in pharmaceutical field (Scheme 1), were reported. Two kinds of complexes were obtained with derivative sulfonamide, [M (L)₂ (H₂O)₂].H₂O and [M (L)₂ (Cl)₂]3H₂O. These complexes have been prepared and characterized by elemental analysis, FAB mass, ESR magnetic measurements, FTIR, UV-Visible spectra and conductivity. Their stability constants have been determined by potentiometric methods in a water-ethanol (90:10 v/v) mixture at a 0.2 mol l-1 ionic strength (NaCl) and at 25.0 ± 0.1 ºC using Sirko program. DFT calculations were done using B3LYP/6-31G(d) and B3LYP/LanL2DZ. The antimicrobial activity of ligand and complexes against the species Escherichia coli, P. aeruginosa, Klebsiella pneumoniae, S. aureus, Bacillus subtilisan, Candida albicans, Candida tropicalis, Saccharomyces, Aspergillus fumigatus and Aspergillus terreus has been carried out and compared using agar-diffusion method. Also, the toxicity study was evaluated on synchesis complexes using Mice of NMRI strain.

Keywords: hetterocyclic ligand, complex, stability constant, antimicrobial activity, DFT, acute and genotoxicity study

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1862 The Use of Classifiers in Image Analysis of Oil Wells Profiling Process and the Automatic Identification of Events

Authors: Jaqueline Maria Ribeiro Vieira

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Different strategies and tools are available at the oil and gas industry for detecting and analyzing tension and possible fractures in borehole walls. Most of these techniques are based on manual observation of the captured borehole images. While this strategy may be possible and convenient with small images and few data, it may become difficult and suitable to errors when big databases of images must be treated. While the patterns may differ among the image area, depending on many characteristics (drilling strategy, rock components, rock strength, etc.). Previously we developed and proposed a novel strategy capable of detecting patterns at borehole images that may point to regions that have tension and breakout characteristics, based on segmented images. In this work we propose the inclusion of data-mining classification strategies in order to create a knowledge database of the segmented curves. These classifiers allow that, after some time using and manually pointing parts of borehole images that correspond to tension regions and breakout areas, the system will indicate and suggest automatically new candidate regions, with higher accuracy. We suggest the use of different classifiers methods, in order to achieve different knowledge data set configurations.

Keywords: image segmentation, oil well visualization, classifiers, data-mining, visual computer

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1861 Estimation of Seismic Drift Demands for Inelastic Shear Frame Structures

Authors: Ali Etemadi, Polat H. Gulkan

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The drift spectrum derived through the continuous shear-beam and wave propagation theory is known to be useful appliance to measure of the demand of pulse like near field ground motions on building structures. As regards, many of old frame buildings with poor or non-ductile column elements, pass the elastic limits and blurt the post yielding hysteresis degradation responses when subjected to such impulsive ground motions. The drift spectrum which, is based on a linear system cannot be predicted the overestimate drift demands arising from inelasticity in an elastic plastic systems. A simple procedure to estimate the drift demands in shear-type frames which, respond over the elastic limits is described and effect of hysteresis degradation behavior on seismic demands is clarified. Whereupon the modification factors are proposed to incorporate the hysteresis degradation effects parametrically. These factors are defined with respected to the linear systems. The method can be applicable for rapid assessment of existing poor detailed, non-ductile buildings.

Keywords: drift spectrum, shear-type frame, stiffness and strength degradation, pinching, smooth hysteretic model, quasi static analysis

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1860 The Analysis of Competitive Balance Progress among Five Most Valuable Football Leagues from 1966 to 2015

Authors: Seyed Salahedin Naghshbandi, Zahra Bozorgzadeh, Leila Zakizadeh, Siavash Hamidzadeh

Abstract:

From the sport economy experts point of view, the existence of competitive balance among sport leagues and its numerous effects on league is an important and undeniable issue. In general, sport events fans are so eager to unpredictable results of competition in order to reach the top of excitement and necessary motivation for following competitions. The purpose of this research is to consider and compare the competitive balance among five provisional European football leagues (Spain, England, Italy, France and Germany) during 1966 - 2015 seasons. Research data are secondary and obtained from Premier League final tables of selected countries in 1966 - 2015 seasons. For analyzing data, C5 and C5ICB indicators used. whatever these indicators be less, more balance establishes in the league and vice-versa. The result showed that Le champion of France reached from 1,259 to 1,395; Italy Serie-A league from 1,316 to 1,432; England premier league from 1, 342 to 1,455; Germany Bundesliga from 1,238 to 1,465 and Spain La liga from 1,295 to 1,495. So by comparing C5ICB charts during 1966 - 2015 seasons, La liga of Spain moved more toward imbalance and enjoyed less balance with other European Leagues. Also, La champion of France during the mentioned season, enjoyed less imbalance and preserved its relative balance with monotonous process. It seems that football in France has been followed as stable during 1966 to 2015, and prediction of results was more difficult and competitions were so attractive for spectators, but in Italy, England, Germany, and Spain there were less balance, respectively.

Keywords: competitive balance, professional football league, competition, C5ICB

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1859 Understanding Parental Style and Its Effect on the Wellbeing of Adolescents with Epilepsy

Authors: Arthy Vinayakam, Emilda Judith Ezhil Rajan

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Adolescents with epilepsy living in developing country like India face many difficulties on stigma towards the disease. The psychological wellbeing of adolescents who are living with epilepsy has a varied influence on their daily activities and decision-making. Parental involvement with adolescents has always been a subject of caution. The dynamics in adolescents with epilepsy is much varied as their parental aspects has been known to have an impact on their education, socialization and wellbeing. The current study aims to identify the effect of parental styles, how they tend to effect the perception of self-concept that relate to the stigma in adolescents with epilepsy. A sample of 30 adolescents with epilepsy and their parents were taken; a control group of 30 adolescents and their parents were also taken. The General Health Questionnaire -12 was used as a screening for both groups to be included in the study. Parents were evaluated with Parenting Practices Questionnaire (PPQ). Adolescents were administered the Epilepsy Stigma Scale (ESS), Rosenberg Self-esteem Scale (RSS) and Adolescent Wellbeing Scale (AWS). Descriptive statistics was used to analyze the data. The findings of the study highlight the challenges of both parent and their influence on adolescent’s wellbeing. The findings also establish the impact of parenting style on the stigma in adolescents having epilepsy and how this influences their self-concept whereby their emotional strength.

Keywords: epilepsy, parenting style, stigma, wellbeing

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1858 Somatic Embryogenesis Derived from Protoplast of Murraya Paniculata L. Jack and Their Regeneration into Plant Flowering in vitro

Authors: Hasan Basri Jumin

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The in vitro flowering of orange jessamine plantlets derived from protoplast was affected by the manipulation of plant growth regulators, sugar and light conditions. MT basal medium containing 5% sucrose and supplemented with 0.001 mg 1-1 indole-acetic-acid was found to be a suitable medium for development of globular somatic embryos derived from protoplasts to form heart-shaped somatic embryos with cotyledon-like structures. The highest percentage (85 %) of flowering was achieved with plantlet on half-strength MT basal medium containing 5% sucrose and 0.001 mg1-1 indole-acetic-acid in light. Exposure to darkness for more than 3 weeks followed by re-exposure to light reduced flowering. Flowering required a 10-day exposure to indole-acetic-acid. Photoperiod with 18 h and 79.4 µmol m-2 s-1 light intensity promoted in vitro flowering in high frequencies. The sucrose treatment affected the flower bud size distribution. Flower buds originating from plantlet derived from protoplasts developed into normal flowers.

Keywords: indole-acetc-acid, light-intensity, Murraya-paniculata, photoperiod, plantlet, Zeatin

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1857 Numerical Simulation of Free Surface Water Wave for the Flow Around NACA 0012 Hydrofoil and Wigley Hull Using VOF Method

Authors: Omar Imine, Mohammed Aounallah, Mustapha Belkadi

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Steady three-dimensional and two free surface waves generated by moving bodies are presented, the flow problem to be simulated is rich in complexity and poses many modeling challenges because of the existence of breaking waves around the ship hull, and because of the interaction of the two-phase flow with the turbulent boundary layer. The results of several simulations are reported. The first study was performed for NACA0012 of hydrofoil with different meshes, this section is analyzed at h/c= 1, 0345 for 2D. In the second simulation, a mathematically defined Wigley hull form is used to investigate the application of a commercial CFD code in prediction of the total resistance and its components from tangential and normal forces on the hull wetted surface. The computed resistance and wave profiles are used to estimate the coefficient of the total resistance for Wigley hull advancing in calm water under steady conditions. The commercial CFD software FLUENT version 12 is used for the computations in the present study. The calculated grid is established using the code computer GAMBIT 2.3.26. The shear stress k-ωSST model is used for turbulence modeling and the volume of the fluid technique is employed to simulate the free-surface motion. The second order upwind scheme is used for discretizing the convection terms in the momentum transport equations, the Modified HRICscheme for VOF discretization. The results obtained compare well with the experimental data.

Keywords: free surface flows, breaking waves, boundary layer, Wigley hull, volume of fluid

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1856 Identification and Quantification of Acid Sites of M(X)X Zeolites (M= Cu2+ and/or Zn2+,X = Level of Exchange): An In situ FTIR Study Using Pyridine Adsorption/Desorption

Authors: H. Hammoudi, S. Bendenia, I. Batonneau-Gener, J. Comparot, K. Marouf-Khelifa, A. Khelifa

Abstract:

X zeolites were prepared by ion-exchange with Cu2+ and/or Zn2+ cations, at different concentrations of the exchange solution, and characterised by thermal analysis and nitrogen adsorption. The acidity of the samples was investigated by pyridine adsorption–desorption followed by in situ Fourier transform infrared (FTIR) spectroscopy. Desorption was carried out at 150, 250 and 350 °C. The objective is to estimate the nature and concentration of acid sites. A comparison between the binary (Cu(x)X, Zn(x)X) and ternary (CuZn(x)X) exchanges was also established (x = level of exchange) through the Cu(43)X, Zn(48)X and CuZn(50)X samples. Lewis acidity decreases overall with desorption temperature and the level of exchange. As the latter increases, there is a conversion of some Lewis sites into those of Brønsted during thermal treatment. In return, the concentration of Brønsted sites increases with the degree of exchange. The Brønsted acidity of CuZn(50)X at 350 °C is more important than the sum of those of Cu(43)X and Zn(48)X. The found values were 73, 32 and 15 μmol g-1, respectively. Besides, the concentration of Brønsted sites for CuZn(50)X increases with desorption temperature. These features indicate the presence of a synergistic effect amplifying the strength of these sites when Cu2+ and Zn2+ cations compete for the occupancy of sites distributed inside zeolitic cavities.

Keywords: acidity, adsorption, pyridine, zeolites

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1855 A Data-Driven Approach for Studying the Washout Effects of Rain on Air Pollution

Authors: N. David, H. O. Gao

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Air pollution is a serious environmental threat on a global scale and can cause harm to human health, morbidity and premature mortality. Reliable monitoring and control systems are therefore necessary to develop coping skills against the hazards associated with this phenomenon. However, existing environmental monitoring means often do not provide a sufficient response due to practical and technical limitations. Commercial microwave links that form the infrastructure for transmitting data between cell phone towers can be harnessed to map rain at high tempo-spatial resolution. Rainfall causes a decrease in the signal strength received by these wireless communication links allowing it to be used as a built-in sensor network to map the phenomenon. In this study, we point to the potential that lies in this system to indirectly monitor areas where air pollution is reduced. The relationship between pollutant wash-off and rainfall provides an opportunity to acquire important spatial information about air quality using existing cell-phone tower signals. Since the density of microwave communication networks is high relative to any dedicated sensor arrays, it could be possible to rely on this available observation tool for studying precipitation scavenging on air pollutants, for model needs and more.

Keywords: air pollution, commercial microwave links, rainfall, washout

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1854 Optimum Design of Tall Tube-Type Building: An Approach to Structural Height Premium

Authors: Ali Kheyroddin, Niloufar Mashhadiali, Frazaneh Kheyroddin

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In last decades, tubular systems employed for tall buildings were efficient structural systems. However, increasing the height of a building leads to an increase in structural material corresponding to the loads imposed by lateral loads. Based on this approach, new structural systems are emerging to provide strength and stiffness with the minimum premium for height. In this research, selected tube-type structural systems such as framed tubes, braced tubes, diagrids and hexagrid systems were applied as a single tube, tubular structures combined with braced core and outrigger trusses on a set of 48, 72, and 96-story, respectively, to improve integrated structural systems. This paper investigated structural material consumption by model structures focusing on the premium for height. Compared analytical results indicated that as the height of the building increased, combination of the structural systems caused the framed tube, hexagrid and braced tube system to pay fewer premiums to material tonnage while in diagrid system, combining the structural system reduced insignificantly the steel material consumption.

Keywords: braced tube, diagrid, framed tube, hexagrid

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1853 Development of High Temperature Mo-Si-B Based In-situ Composites

Authors: Erhan Ayas, Buse Katipoğlu, Eda Metin, Rifat Yılmaz

Abstract:

The search for new materials has begun to be used even higher than the service temperature (~1150ᵒC) where nickel-based superalloys are currently used. This search should also meet the increasing demands for energy efficiency improvements. The materials studied for aerospace applications are expected to have good oxidation resistance. Mo-Si-B alloys, which have higher operating temperatures than nickel-based superalloys, are candidates for ultra-high temperature materials used in gas turbine and jet engines. Because the Moss and Mo₅SiB₂ (T2) phases exhibit high melting temperature, excellent high-temperature creep strength and oxidation resistance properties, however, low fracture toughness value at room temperature is a disadvantage for these materials, but this feature can be improved with optimum Moss phase and microstructure control. High-density value is also a problem for structural parts. For example, in turbine rotors, the higher the weight, the higher the centrifugal force, which reduces the creep life of the material. The density value of the nickel-based superalloys and the T2 phase, which is the Mo-Si-B alloy phase, is in the range of 8.6 - 9.2 g/cm³. But under these conditions, T2 phase Moss (density value 10.2 g/cm³), this value is above the density value of nickel-based superalloys. So, with some ceramic-based contributions, this value is enhanced by optimum values.

Keywords: molybdenum, composites, in-situ, mmc

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1852 Multi-Point Dieless Forming Product Defect Reduction Using Reliability-Based Robust Process Optimization

Authors: Misganaw Abebe Baye, Ji-Woo Park, Beom-Soo Kang

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The product quality of multi-point dieless forming (MDF) is identified to be dependent on the process parameters. Moreover, a certain variation of friction and material properties may have a substantially worse influence on the final product quality. This study proposed on how to compensate the MDF product defects by minimizing the sensitivity of noise parameter variations. This can be attained by reliability-based robust optimization (RRO) technique to obtain the optimal process setting of the controllable parameters. Initially two MDF Finite Element (FE) simulations of AA3003-H14 saddle shape showed a substantial amount of dimpling, wrinkling, and shape error. FE analyses are consequently applied on ABAQUS commercial software to obtain the correlation between the control process setting and noise variation with regard to the product defects. The best prediction models are chosen from the family of metamodels to swap the computational expensive FE simulation. Genetic algorithm (GA) is applied to determine the optimal process settings of the control parameters. Monte Carlo Analysis (MCA) is executed to determine how the noise parameter variation affects the final product quality. Finally, the RRO FE simulation and the experimental result show that the amendment of the control parameters in the final forming process leads to a considerably better-quality product.

Keywords: dimpling, multi-point dieless forming, reliability-based robust optimization, shape error, variation, wrinkling

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1851 In-silico Antimicrobial Activity of Bioactive Compounds of Ricinus communis against DNA Gyrase of Staphylococcus aureus as Molecular Target

Authors: S. Rajeswari

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Medicinal Plant extracts and their bioactive compounds have been used for antimicrobial activities and have significant remedial properties. In the recent years, a wide range of investigations have been carried out throughout the world to confirm antimicrobial properties of different medicinally important plants. A number of plants showed efficient antimicrobial activities, which were comparable to that of synthetic standard drugs or antimicrobial agents. The large family Euphorbiaceae contains nearly about 300 genera and 7,500 speciesand one among is Ricinus communis or castor plant which has high traditional and medicinal value for disease free healthy life. Traditionally the plant is used as laxative, purgative, fertilizer and fungicide etc. whereas the plant possess beneficial effects such as anti-oxidant, antihistamine, antinociceptive, antiasthmatic, antiulcer, immunomodulatory anti diabetic, hepatoprotective, anti inflammatory, antimicrobial, and many other medicinal properties. This activity of the plant possess due to the important phytochemical constituents like flavonoids, saponins, glycosides, alkaloids and steroids. The presents study includes the phytochemical properties of Ricinus communis and to prediction of the anti-microbial activity of Ricinus communis using DNA gyrase of Staphylococcus aureus as molecular target. Docking results of varies chemicals compounds of Ricinus communis against DNA gyrase of Staphylococcus aureus by maestro 9.8 of Schrodinger show that the phytochemicals are effective against the target protein DNA gyrase. our studies suggest that the phytochemical from Ricinus communis such has INDICAN (G.Score 4.98) and SUPLOPIN-2(G.Score 5.74) can be used as lead molecule against Staphylococcus infections.

Keywords: euphorbiaceae, antimicrobial activity, Ricinus communis, Staphylococcus aureus

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1850 Comparative Sulphate Resistance of Pozzolanic Cement Mortars

Authors: Mahmud Abba Tahir

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This is report on experiment out to compare the sulphate resistance of sand mortar made with five different pozzolanic cement. The pozzolanic cement were prepared by blending powered burnt bricks from the Adamawa, Makurdi, Kano, Kaduna and Niger bricks factories with ordinary Portland cement in the ratio 1:4. Sand –pozzolanic cement mortars of mix ratio 1:6 and 1:3 with water-cement ratio of 0.65 and 0.40 respectively were used to prepare cubes and bars specimens. 150 mortar cubes of size 70mm x 70mm x 70mm and 35 mortar bars of 15mm x 15mm x 100mm dimensions were cast and cured for 28 days. The cured specimens then immersed in the solutions of K2SO4, (NH4)2SO4 and water for 28 days and then tested. The compressive strengths of cubes in water increased by 34% while those in the sulphate solutions decreased. Strength decreases of the cubes, cracking and warping of bars immersed in K2SO4 were less than those in (NH4)2SO4. Specimens made with Niger and Makurdi pulverized burnt bricks experienced less effect of the sulphates and can therefore be used as pozzolan in mortar and concrete to resist sulphate.

Keywords: burnt bricks powder, comparative, pozzolanic cement, sulphates

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1849 Millennials' Viewpoints about Sustainable Hotels' Practices in Egypt: Promoting Responsible Consumerism

Authors: Jailan Mohamed El Demerdash

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Millennials are a distinctive and dominant consumer group whose behavior, preferences and purchase decisions are broadly explored but not fully understood yet. Making up the largest market segment in the world, and in Egypt, they have the power to reinvent the hospitality industry and contribute to forming prospective demand for green hotels by showing willingness to adopting their environmental-friendly practices. The current study aims to enhance better understanding of Millennials' perception about sustainable initiatives and to increase the prediction power of their intentions regarding green hotel practices in Egypt. In doing so, the study is exploring the relation among different factors; Millennials' environmental awareness, their acceptance of green practices and their willingness to pay more for them. Millennials' profile, their preferences and environmental decision-making process are brought under light to stimulate actions of hospitality decision-makers and hoteliers. Bearing in mind that responsible consumerism is depending on understanding the different influences on consumption. The study questionnaire was composed of four sections and it was distributed to random Egyptian travelers' blogs and Facebook groups, with approximately 8000 members. Analysis of variance test (ANOVA) was used to examine the study variables. The findings indicated that Millennials' environmental awareness will not be a significant factor in their acceptance of hotel green practices, as well as, their willingness to pay more for them. However, Millennials' acceptance of the level of hotel green practices will have an impact on their willingness to pay more. Millennials were found to have a noticeable level of environmental awareness but lack commitment to tolerating hotel green practices and their associated high prices.

Keywords: millennials, environment, awareness, paying more

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1848 Non-Linear Assessment of Chromatographic Lipophilicity of Selected Steroid Derivatives

Authors: Milica Karadžić, Lidija Jevrić, Sanja Podunavac-Kuzmanović, Strahinja Kovačević, Anamarija Mandić, Aleksandar Oklješa, Andrea Nikolić, Marija Sakač, Katarina Penov Gaši

Abstract:

Using chemometric approach, the relationships between the chromatographic lipophilicity and in silico molecular descriptors for twenty-nine selected steroid derivatives were studied. The chromatographic lipophilicity was predicted using artificial neural networks (ANNs) method. The most important in silico molecular descriptors were selected applying stepwise selection (SS) paired with partial least squares (PLS) method. Molecular descriptors with satisfactory variable importance in projection (VIP) values were selected for ANN modeling. The usefulness of generated models was confirmed by detailed statistical validation. High agreement between experimental and predicted values indicated that obtained models have good quality and high predictive ability. Global sensitivity analysis (GSA) confirmed the importance of each molecular descriptor used as an input variable. High-quality networks indicate a strong non-linear relationship between chromatographic lipophilicity and used in silico molecular descriptors. Applying selected molecular descriptors and generated ANNs the good prediction of chromatographic lipophilicity of the studied steroid derivatives can be obtained. This article is based upon work from COST Actions (CM1306 and CA15222), supported by COST (European Cooperation and Science and Technology).

Keywords: artificial neural networks, chemometrics, global sensitivity analysis, liquid chromatography, steroids

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1847 Large Eddy Simulation with Energy-Conserving Schemes: Understanding Wind Farm Aerodynamics

Authors: Dhruv Mehta, Alexander van Zuijlen, Hester Bijl

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Large Eddy Simulation (LES) numerically resolves the large energy-containing eddies of a turbulent flow, while modelling the small dissipative eddies. On a wind farm, these large scales carry the energy wind turbines extracts and are also responsible for transporting the turbines’ wakes, which may interact with downstream turbines and certainly with the atmospheric boundary layer (ABL). In this situation, it is important to conserve the energy that these wake’s carry and which could be altered artificially through numerical dissipation brought about by the schemes used for the spatial discretisation and temporal integration. Numerical dissipation has been reported to cause the premature recovery of turbine wakes, leading to an over prediction in the power produced by wind farms.An energy-conserving scheme is free from numerical dissipation and ensures that the energy of the wakes is increased or decreased only by the action of molecular viscosity or the action of wind turbines (body forces). The aim is to create an LES package with energy-conserving schemes to simulate wind turbine wakes correctly to gain insight into power-production, wake meandering etc. Such knowledge will be useful in designing more efficient wind farms with minimal wake interaction, which if unchecked could lead to major losses in energy production per unit area of the wind farm. For their research, the authors intend to use the Energy-Conserving Navier-Stokes code developed by the Energy Research Centre of the Netherlands.

Keywords: energy-conserving schemes, modelling turbulence, Large Eddy Simulation, atmospheric boundary layer

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1846 Deformation Behavior of Virgin and Polypropylene Modified Bituminous Mixture

Authors: Noor Zainab Habib, Ibrahim Kamaruddin, Madzlan Napiah

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This paper present a part of research conducted to investigate the creep behavior of bituminous concrete mixture prepared with well graded using the dynamic creep test. The samples were prepared from unmodified control mix and Polypropylene modified bituminous mix. Unmodified or control mix was prepared with 80/100 grade bitumen while polypropylene modified mix was prepared using polypropylene PP polymer as modifier, blended with 80/100 Pen bitumen. The concentration of polymer in the blend was kept at 1%, 2%, and 3% by weight of bitumen content. For Dynamic Creep Test, Marshall Specimen were prepared at optimum bitumen content and then tested using IPC Global Universal Testing Machine (UTM), in order to investigate the creep stiffness of both modified and control mix. From the results obtained it was found that 1% and 2% PP modified bituminous mix offer better results in comparison to control and 3% PP modified mix samples. The results verify all the findings of empirical and viscosity test results which indicates that polymer modification induces stiffening effect in the binder. Enhanced viscous component of the binder was considered responsible for this change which eventually enhances the mechanical strength of the modified bituminous mixes.

Keywords: polymer modified bitumen, stiffness, creep, viscosity

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1845 Human-Induced Vibration and Degree of Human Comfortability Analysis of Intersection Pedestrian Bridge

Authors: Yaowen Sheng, Jiuxian Liu

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In order to analyze the pedestrian bridge dynamic characteristics and degree of comfortability, the finite element method and live load time history method is used to calculate the dynamic response of the bridge. The example bridge’s dynamic characteristics and degree of human comfortability need to be analyzed. The project background is a three-way intersection. The intersection has three side blocks. An intersection bridge is designed to help people cross the streets. The finite element model of the bridge is established by the Midas/Civil software, and the analysis of the model is done. The strength, stiffness, and stability checks are also completed. Apart from the static analysis of the bridge, the dynamic analysis of the bridge is also completed to avoid the problems resulted from vibrations. The results show that the pedestrian bridge has different dynamic characteristics compared to other normal bridges. The degree of human comfortability satisfies the requirements of Chinese and British specifications. The live load time history method can be used to calculate the dynamic response of the bridge.

Keywords: pedestrian bridge, steel box girder, human-induced vibration, finite element analysis, degree of human comfortability

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1844 The Mediating Effect of Resilience on the Relationship between Cultural Identity and Self-Concordance among Tibetan, Han and Hui Students

Authors: Chunhua Ma

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Background: There is a relationship between cultural identity and psychological health. Resilience is an important factor of psychological health, and cultural identity will protect the resilience. The research showed that the cultural identity, resilience, and self-concordance of students from different cultures. It should be a theoretical basis to improve mental health of different nationalities students. And the role of resilience factors for adults’ cultural identity and self-concordance was deserve studied. Aims: The current study aimed to examine the relationship between cultural identity and self-concordance among Chinese academician from 3 minorities, postulating mediating by resilience. Methods: This study used cross-sectional and correlational design. Participants were 328 Chinese aged between 18 and 25 years. Data was collected via self-reports including both closed and opened questions. Results: Linear regression analysis controlling for age, gender, the result showed that: (a) Cultural identity was related to self-concordance, resilience was related to self-concordance and cultural identity was related to resilience, (b) Resilience mediated the link between cultural identity and self-concordance, respectively. Discussion: Our findings suggested that resilience and cultural identity are important factors in self-concordance. If minority college students realized the heterogeneous culture, it would alleviate their psychological conflict, stimulate their strength potential and improve their self-concordance.

Keywords: cultural identity, resilience, self-concordance, mediating effect

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1843 Long-Term Sitting Posture Identifier Connected with Cloud Service

Authors: Manikandan S. P., Sharmila N.

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Pain in the neck, intermediate and anterior, and even low back may occur in one or more locations. Numerous factors can lead to back discomfort, which can manifest into sensations in the other parts of your body. Up to 80% of people will have low back problems at a certain stage of their lives, making spine-related pain a highly prevalent ailment. Roughly twice as commonly as neck pain, low back discomfort also happens about as often as knee pain. According to current studies, using digital devices for extended periods of time and poor sitting posture are the main causes of neck and low back pain. There are numerous monitoring techniques provided to enhance the sitting posture for the aforementioned problems. A sophisticated technique to monitor the extended sitting position is suggested in this research based on this problem. The system is made up of an inertial measurement unit, a T-shirt, an Arduino board, a buzzer, and a mobile app with cloud services. Based on the anatomical position of the spinal cord, the inertial measurement unit was positioned on the inner back side of the T-shirt. The IMU (inertial measurement unit) sensor will evaluate the hip position, imbalanced shoulder, and bending angle. Based on the output provided by the IMU, the data will be analyzed by Arduino, supplied through the cloud, and shared with a mobile app for continuous monitoring. The buzzer will sound if the measured data is mismatched with the human body's natural position. The implementation and data prediction with design to identify balanced and unbalanced posture using a posture monitoring t-shirt will be further discussed in this research article.

Keywords: IMU, posture, IOT, textile

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1842 Study of Effective Parameters on Mechanical Properties of Toughened PP Compounds in Presence of Biofillers and Blowing Agents

Authors: Koosha Rezaei, Mehdi Moghri bidgoli, Mazyar Khakpour

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Wood-plastic composites foam is one of the most used products were the industry today. In this study, composite foam polypropylene in the presence of different biofilers such as Spruce wood, wheat and rice husk as well as 3 different types toughening agents such as polyolefin elastomer, styrene butadiene styrene and styrene-ethylene butadiene styrene, and two types of cause blowing agents azodicarbonamide and sodium bicarbonate was prepared. For improving dispersion of biofilers, in the mixing process we used polypropylene coupling agent grafted with maleic anhydride. Due to the large number of variables, the statistical analysis of response surface to analyze the results of the impact test, tensile modulus and tensile strength and modeling were used. Co-rotating twine extruder was made composite melt mixing method and then to perform mechanical tests using injection molding, respectively.Images from electron microscopy showed cell sandwich structure in composite amply demonstrates.

Keywords: polypropylene, wood plastic composite foam, response surface analysis, morphology, mechanical properties

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1841 The Research of the Relationship between Triathlon Competition Results with Physical Fitness Performance

Authors: Chen Chan Wei

Abstract:

The purpose of this study was to investigate the impact of swim 1500m, 10000m run, VO2 max, and body fat on Olympic distance triathlon competition performance. The subjects were thirteen college triathletes with endurance training, with an average age, height and weight of 20.61±1.04 years (mean ± SD), 171.76±8.54 cm and 65.32±8.14 kg respectively. All subjects were required to take the tests of swim 1500m, run 10000m, VO2 max, body fat, and participate in the Olympic distance triathlon competition. First, the swim 1500m test was taken in the standardized 50m pool, with a depth of 2m, and the 10000m run test on the standardized 400m track. After three days, VO2 max was tested with the MetaMax 3B and body fat was measured with the DEXA machine. After two weeks, all 13 subjects joined the Olympic distance triathlon competition at the 2016 New Taipei City Asian Cup. The relationships between swim 1500m, 10000m run, VO2 max, body fat test, and Olympic distance triathlon competition performance were evaluated using Pearson's product-moment correlation. The results show that 10000m run and body fat had a significant positive correlation with Olympic distance triathlon performance (r=.830, .768), but VO2 max has a significant negative correlation with Olympic distance triathlon performance (r=-.735). In conclusion, for improved non-draft Olympic distance triathlon performance, triathletes should focus on running than swimming training and can be measure VO2 max to prediction triathlon performance. Also, managing body fat can improve Olympic distance triathlon performance. In addition, swimming performance was not significantly correlated to Olympic distance triathlon performance, possibly because the 2016 New Taipei City Asian Cup age group was not a drafting competition. The swimming race is the shortest component of Olympic distance triathlons. Therefore, in a non-draft competition, swimming ability is not significantly correlated with overall performance.

Keywords: triathletes, olympic, non-drafting, correlation

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1840 Evaluation of Hard Rocks Destruction Effectiveness at Drilling

Authors: Ekaterina Leusheva, Valentin Morenov

Abstract:

Well drilling in hard rocks is coupled with high energy demands which negates the speed of the process and thus reduces overall effectiveness. Aim of this project is to develop the technique of experimental research, which would allow to select optimal washing fluid composition while adding special hardness reducing detergent reagents. Based on the analysis of existing references and conducted experiments, technique dealing with quantitative evaluation of washing fluid weakening influence on drilled rocks was developed, which considers laboratory determination of three mud properties (density, surface tension, specific electrical resistance) and three rock properties (ultimate stress, dynamic strength, micro-hardness). Developed technique can be used in the well drilling technologies and particularly while creating new compositions of drilling muds for increased destruction effectiveness of hard rocks. It can be concluded that given technique introduces coefficient of hard rocks destruction effectiveness that allows quantitative evaluation of different drilling muds on the drilling process to be taken. Correct choice of drilling mud composition with hardness reducing detergent reagents will increase drilling penetration rate and drill meterage per bit.

Keywords: detergent reagents, drilling mud, drilling process stimulation, hard rocks

Procedia PDF Downloads 547
1839 Investigation of the Recycling of Geopolymer Cement Wastes as Fine Aggregates in Mortar Mixes

Authors: Napoleana-Anna Chaliasou, Andrew Heath, Kevin Paine

Abstract:

Fly ash-slag based Geopolymer Cement (GPC) is presenting mechanical properties and environmental advantages that make it the predominant “green” alternative to Portland Cement (PC). Although numerous life-cycle analyses praising its environmental advantages, disposal after the end of its life remains as an issue that has been barely explored. The present study is investigating the recyclability of fly ash-slag GPC as aggregate in mortars. The purpose of the study was to evaluate the effect of GPC fine Recycled Aggregates (RA), at replacement levels of 25% and 50%, on the main mechanical properties of PC and GPC mortar mixes. The results were compared with those obtained by corresponding mixes incorporating natural and PC-RA. The main physical properties of GPC-RA were examined and proven to be comparable to those of PC-RA and slightly inferior to those of natural sand. A negligible effect was observed at 28-day compressive and flexural strength of PC mortars with GPC aggregates having a milder effect than PC. As far as GPC mortars are concerned, the influence of GPC aggregates was enhancing for the investigated mechanical properties. Additionally, a screening test showed that recycled geopolymer aggregates are not prone of inducing alkali silica reaction.

Keywords: concrete recycling, geopolymer cement, fly ash, construction wastes

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1838 Public Wi-Fi Security Threat Evil Twin Attack Detection Based on Signal Variant and Hop Count

Authors: Said Abdul Ahad Ahadi, Elyas Baray, Nitin Rakesh, Sudeep Varshney

Abstract:

Wi-Fi is a widely used internet source that is used to provide internet access in many areas such as Stores, Cafes, University campuses, Restaurants and so on. This technology brought more facilities in communication and networking. On the other hand, due to the transmission of data over the air, which makes the network vulnerable, so it becomes prone to various threats such as Evil Twin and etc. The Evil Twin is a kind of adversary which impersonates a legitimate access point (LAP) as it can happen by spoofing the name (SSID) and MAC address (BSSID) of a legitimate access point (LAP). And this attack can cause many threats such as MITM, Service Interruption, Access point service blocking. Various Evil Twin Attack Detection Techniques are proposed, but they require additional hardware, or they require protocol modification. In this paper, we proposed a new technique based on Access Point’s two fingerprints, Received Signal Strength Indicator (RSSI) and Hop Count, that is hard to copy by an adversary. And we implemented the technique in a system called “ETDetector,” which can detect and prevent the attack.

Keywords: evil twin, LAP, SSID, Wi-Fi security, signal variation, ETAD, kali linux, scapy, python

Procedia PDF Downloads 143
1837 Interpretation and Prediction of Geotechnical Soil Parameters Using Ensemble Machine Learning

Authors: Goudjil kamel, Boukhatem Ghania, Jlailia Djihene

Abstract:

This paper delves into the development of a sophisticated desktop application designed to calculate soil bearing capacity and predict limit pressure. Drawing from an extensive review of existing methodologies, the study meticulously examines various approaches employed in soil bearing capacity calculations, elucidating their theoretical foundations and practical applications. Furthermore, the study explores the burgeoning intersection of artificial intelligence (AI) and geotechnical engineering, underscoring the transformative potential of AI- driven solutions in enhancing predictive accuracy and efficiency.Central to the research is the utilization of cutting-edge machine learning techniques, including Artificial Neural Networks (ANN), XGBoost, and Random Forest, for predictive modeling. Through comprehensive experimentation and rigorous analysis, the efficacy and performance of each method are rigorously evaluated, with XGBoost emerging as the preeminent algorithm, showcasing superior predictive capabilities compared to its counterparts. The study culminates in a nuanced understanding of the intricate dynamics at play in geotechnical analysis, offering valuable insights into optimizing soil bearing capacity calculations and limit pressure predictions. By harnessing the power of advanced computational techniques and AI-driven algorithms, the paper presents a paradigm shift in the realm of geotechnical engineering, promising enhanced precision and reliability in civil engineering projects.

Keywords: limit pressure of soil, xgboost, random forest, bearing capacity

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1836 Air Dispersion Model for Prediction Fugitive Landfill Gaseous Emission Impact in Ambient Atmosphere

Authors: Moustafa Osman Mohammed

Abstract:

This paper will explore formation of HCl aerosol at atmospheric boundary layers and encourages the uptake of environmental modeling systems (EMSs) as a practice evaluation of gaseous emissions (“framework measures”) from small and medium-sized enterprises (SMEs). The conceptual model predicts greenhouse gas emissions to ecological points beyond landfill site operations. It focuses on incorporation traditional knowledge into baseline information for both measurement data and the mathematical results, regarding parameters influence model variable inputs. The paper has simplified parameters of aerosol processes based on the more complex aerosol process computations. The simple model can be implemented to both Gaussian and Eulerian rural dispersion models. Aerosol processes considered in this study were (i) the coagulation of particles, (ii) the condensation and evaporation of organic vapors, and (iii) dry deposition. The chemical transformation of gas-phase compounds is taken into account photochemical formulation with exposure effects according to HCl concentrations as starting point of risk assessment. The discussion set out distinctly aspect of sustainability in reflection inputs, outputs, and modes of impact on the environment. Thereby, models incorporate abiotic and biotic species to broaden the scope of integration for both quantification impact and assessment risks. The later environmental obligations suggest either a recommendation or a decision of what is a legislative should be achieved for mitigation measures of landfill gas (LFG) ultimately.

Keywords: air pollution, landfill emission, environmental management, monitoring/methods and impact assessment

Procedia PDF Downloads 324
1835 Chemical Stability of Ceramic Crucibles to Molten Titanium

Authors: Jong-Min Park, Hyung-Ki Park, Seok Hong Min, Tae Kwon Ha

Abstract:

Titanium is widely used due to its high specific strength, good biocompatibility, and excellent corrosion resistance. In order to produce titanium powders, it is necessary to melt titanium, and generally it is conducted by an induction heating method using Al₂O₃ ceramic crucible. However, since titanium reacts chemically with Al₂O₃, it is difficult to melt titanium by the induction heating method using Al₂O₃ crucible. To avoid this problem, we studied the chemical stability of the various crucibles such as Al₂O₃, MgO, ZrO₂, and Y₂O₃ crucibles to molten titanium. After titanium lumps (Grade 2, O(oxygen)<0.25wt%) were placed in each crucible, they were heated to 1800℃ with a heating rate of 5 ℃/min, held at 1800℃ for 30 min, and finally cooled to room temperature with a cooling rate of 5 ℃/min. All heat treatments were carried out in high purity Ar atmosphere. To evaluate the chemical stability, thermodynamic data such as Ellingham diagram were utilized, and also Vickers hardness test, microstructure analysis, and EPMA quantitative analysis were performed. As a result, Al₂O₃, MgO and ZrO₂ crucibles chemically reacted with molten titanium, but Y₂O₃ crucible rarely reacted with it.

Keywords: titanium, induction melting, crucible, chemical stability

Procedia PDF Downloads 301