Search results for: dependent
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2584

Search results for: dependent

1684 Mechanical Behaviours of Ti/GFRP/Ti Laminates with Different Surface Treatments of Titanium Sheets

Authors: Amit Kumar Haldar, Mark Simms, Ian McDevitt, Anthony Comer

Abstract:

Interface properties of fiber metal laminates (FML) affects the integrity and deformation failure modes. In this paper, the mechanical behaviours of Ti/GFRP/Ti laminates were experimentally investigated through low-velocity impact tests. Two different surface treatments of Titanium (Ti-6Al-4V) alloy sheets were prepared to obtain the composite interface properties based on annealing and sandblast surface treatment processes. The deformation failure modes, impact load sustaining ability and energy absorption capacity of FMLs were analysed. The impact load and modulus were shown to be dependent on the surface treatments of Titanium (Ti-6Al-4V) alloy sheets. It was demonstrated that the impact load performance was enhanced when titanium surfaces were annealed and sandblasted. It has also been shown that the values of the strength and energy absorption were slightly higher when the tests conducted at relatively higher loading rate, as a result of the rate-sensitive effects on the damage resistance of the FML.

Keywords: fiber metal laminates, metal composite interface, indentation, low velocity impact

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1683 A Robust Model Predictive Control for a Photovoltaic Pumping System Subject to Actuator Saturation Nonlinearity and Parameter Uncertainties: A Linear Matrix Inequality Approach

Authors: Sofiane Bououden, Ilyes Boulkaibet

Abstract:

In this paper, a robust model predictive controller (RMPC) for uncertain nonlinear system under actuator saturation is designed to control a DC-DC buck converter in PV pumping application, where this system is subject to actuator saturation and parameter uncertainties. The considered nonlinear system contains a linear constant part perturbed by an additive state-dependent nonlinear term. Based on the saturating actuator property, an appropriate linear feedback control law is constructed and used to minimize an infinite horizon cost function within the framework of linear matrix inequalities. The proposed approach has successfully provided a solution to the optimization problem that can stabilize the nonlinear plants. Furthermore, sufficient conditions for the existence of the proposed controller guarantee the robust stability of the system in the presence of polytypic uncertainties. In addition, the simulation results have demonstrated the efficiency of the proposed control scheme.

Keywords: PV pumping system, DC-DC buck converter, robust model predictive controller, nonlinear system, actuator saturation, linear matrix inequality

Procedia PDF Downloads 181
1682 Management and Conservation of Crop Biodiversity in Karnali Mountains of Nepal

Authors: Chhabi Paudel

Abstract:

The food and nutrition security of the people of the mountain of Karnali province of Nepal is dependent on traditional crop biodiversity. The altitude range of the study area is 1800 meters to 2700 meters above sea level. The climate is temperate to alpine. Farmers are adopting subsistent oriented diversified farming systems and selected crop species, cultivars, and local production systems by their own long adaptation mechanism. The major crop species are finger millet, proso millet, foxtail millet, potato, barley, wheat, mountain rice, buckwheat, Amaranths, medicinal plants, and many vegetable species. The genetic and varietal diversity of those underutilized indigenous crops is also very high, which has sustained farming even in uneven climatic events. Biodiversity provides production synergy, inputs, and other agro-ecological services for self-sustainability. But increase in human population and urban accessibility are seen as threats to biodiversity conservation. So integrated conservation measures are suggested, including agro-tourism and other monetary benefits to the farmers who conserve the local biodiversity.

Keywords: crop biodiversity, climate change, in-situ conservation, resilience, sustainability, agrotourism

Procedia PDF Downloads 101
1681 Green Supply Chain Design: A Mathematical Modeling Approach

Authors: Nusrat T. Chowdhury

Abstract:

Green Supply Chain Management (GSCM) is becoming a key to success for profitable businesses. The various activities contributing to carbon emissions in a supply chain are transportation, ordering and holding of inventory. This research work develops a mixed-integer nonlinear programming (MINLP) model that considers the scenario of a supply chain with multiple periods, multiple products and multiple suppliers. The model assumes that the demand is deterministic, the buyer has a limited storage space in each period, the buyer is responsible for the transportation cost, a supplier-dependent ordering cost applies for each period in which an order is placed on a supplier and inventory shortage is permissible. The model provides an optimal decision regarding what products to order, in what quantities, with which suppliers, and in which periods in order to maximize the profit. For the purpose of evaluating the carbon emissions, three different carbon regulating policies i.e., carbon cap-and-trade, the strict cap on carbon emission and carbon tax on emissions, have been considered. The proposed MINLP has been validated using a randomly generated data set.

Keywords: green supply chain, carbon emission, mixed integer non-linear program, inventory shortage, carbon cap-and-trade

Procedia PDF Downloads 241
1680 Dielectric, Energy Storage and Impedance Spectroscopic Studies of Tin Doped Ba₀.₉₈Ca₀.₀₂TiO₃ Lead-Free Ceramics

Authors: Ramovatar, Neeraj Panwar

Abstract:

Lead free Ba₀.₉₈Ca₀.₀₂SnxTi₁₋ₓO₃ (x = 0.01 and 0.05 mole %) ferroelectric ceramics have been synthesized by the solid-state reaction method with sintering at 1400 °C for 2 h. The room temperature x-ray diffraction (XRD) patterns identified the tetragonal phase for x = 0.01 composition whereas co-existence of tetragonal and orthorhombic phases for x =0.05 composition. Raman spectroscopy results corroborated with the XRD results at room temperature. The maximum dielectric properties (ɛm ~ 8591, tanδ ~ 0.018) were obtained for the compound with x = 0.01 at 5 kHz. Further, the tetragonal to cubic (TC) transition temperature was observed at 122 °C and 102 °C for the ceramics with x =0.01 and x = 0.05, respectively. The temperature dependent P-E loops also revealed the existence of TC at these particular temperature values. The energy storage density (Ed) of both compounds was calculated from room temperature P – E loops at an applied electric field of 20 kV/cm. The maximum Ed ~ 224 kJ/m³ was achieved for the sample with x = 0.01 as compared to 164 kJ/m³ for the x =0.05 composition. The value of Ed is comparable to other BaTiO₃ based lead free ferroelectric systems. Impedance spectroscopy analysis exhibited the bulk and grain boundary contributions above 300 °C under the frequency range 100 Hz to 1 MHz. The above properties make these ceramics suitable for energy storage devices.

Keywords: dielectric properties, energy storage properties, impedance spectroscopy, lead free ceramics

Procedia PDF Downloads 153
1679 The Impact of Syntactic Priming on Language Learners’ Perception of Relative Clauses

Authors: Kaine Gulozer

Abstract:

Listening comprehension in a foreign language context has been a constant challenge for Turkish speakers of English. Syntactic priming (SP) of relative clauses might affect the perception of subsequent sentences of identical structure and this could have an impact on the listening comprehension of second or foreign language learners. There has been little attempt to investigate the syntactic priming of English subject relative clauses and object relative clauses in relation to perception for the learners of English in Turkish context. This study investigates SP effects on low-proficiency EFL learners’ production of English relative clauses. Both qualitative and quantitative method along with a pre-test and post-test tasks were adopted, recruiting 62 EFL learners to receive a six-week listening instruction on relative clauses. Testing instruments for language production included the two tasks: (1) the visual- cued presentation and recall and (2) the auditory-cued presentation and recall. Students’ listening comprehension in task 1 and 2 were recorded and transcribed. Fifteen of the participants were also interviewed. The results of the dependent samples t-test analyses revealed that SP had a significant effect on the overall perception of relative clauses.

Keywords: listening comprehension, relative clauses, structural priming, syntactic persistance, syntactic priming

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1678 Using the Nonlocal Theory of Free Vibrations Nanobeam

Authors: Ali Oveysi Sarabi

Abstract:

The dimensions of nanostructures are in the range of inter-atomic spacing of the structures which makes them impossible to be modeled as a continuum. Nanoscale size-effects on vibration analysis of nanobeams embedded in an elastic medium is investigated using different types of beam theory. To this end, Eringen’s nonlocal elasticity is incorporated to various beam theories namely as Euler-Bernoulli beam theory (EBT), Timoshenko beam theory (TBT), Reddy beam theory (RBT), and Levinson beam theory (LBT). The surrounding elastic medium is simulated with both Winkler and Pasternak foundation models and the difference between them is studies. Explicit formulas are presented to obtain the natural frequencies of nanobeam corresponding to each nonlocal beam theory. Selected numerical results are given for different values of the non-local parameter, Winkler modulus parameter, Pasternak modulus parameter and aspect ratio of the beam that imply the effects of them, separately. It is observed that the values of natural frequency are strongly dependent on the stiffness of elastic medium and the value of the non-local parameter and these dependencies varies with the value of aspect ratio and mode number.

Keywords: nanobeams, free vibration, nonlocal elasticity, winkler foundation model, Pasternak foundation model, beam theories

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1677 A Natural Killer T Cell Subset That Protects against Airway Hyperreactivity

Authors: Ya-Ting Chuang, Krystle Leung, Ya-Jen Chang, Rosemarie H. DeKruyff, Paul B. Savage, Richard Cruse, Christophe Benoit, Dirk Elewaut, Nicole Baumgarth, Dale T. Umetsu

Abstract:

We examined characteristics of a Natural Killer T (NKT) cell subpopulation that developed during influenza infection in neonatal mice, and that suppressed the subsequent development of allergic asthma in a mouse model. This NKT cell subset expressed CD38 but not CD4, produced IFN-γ, but not IL-17, IL-4 or IL-13, and inhibited the development of airway hyperreactivity (AHR) through contact-dependent suppressive activity against helper CD4 T cells. The NKT subset expanded in the lungs of neonatal mice after infection with influenza, but also after treatment of neonatal mice with a Th1-biasing α-GalCer glycolipid analogue, Nu-α-GalCer. These results suggest that early/neonatal exposure to infection or to antigenic challenge can affect subsequent lung immunity by altering the profile of cells residing in the lung and that some subsets of NKT cells can have direct inhibitory activity against CD4+ T cells in allergic asthma. Importantly, our results also suggest a potential therapy for young children that might provide protection against the development of asthma.

Keywords: NKT subset, asthma, airway hyperreactivity, hygiene hypothesis, influenza

Procedia PDF Downloads 240
1676 Determination of Thermophysical Properties of Water Based Magnetic Nanofluids

Authors: Eyüphan Manay, Bayram Sahin, Emre Mandev, Ibrahim Ates, Tuba Yetim

Abstract:

In this study, it was aimed to determine the thermophysical properties of two different magnetic nanofluids (NiFe2O4-water and CoFe2O4-water). Magnetic nanoparticles were dispersed into the pure water at different volume fractions from 0 vol.% to 4 vol.%. The measurements were performed in the temperature range of 15 oC-55 oC. In order to get better idea on the temperature dependent thermophysical properties of magnetic nanofluids (MNFs), viscosity and thermal conductivity measurements were made. SEM images of both NiFe2O4 and CoFe2O4 nanoparticles were used in order to confirm the average dimensions. The measurements showed that the thermal conductivity of MNFs increased with an increase in the volume fraction as well as viscosity. Increase in the temperature of both MNFs resulted in an increase in the thermal conductivity and a decrease in the viscosity. Based on the measured data, the correlations for both the viscosity and the thermal conductivity were presented with respect to solid volume ratio and temperature. Effective thermal conductivity of the prepared MNFs was also calculated. The results indicated that water based NiFe2O4 nanofluid had higher thermal conductivity than that of the CoFe2O4. Once the viscosity values of both MNFs were compared, almost no difference was observed.

Keywords: magnetic nanofluids, thermal conductivity, viscosity, nife2o4-water, cofe2o4-water

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1675 Electrokinetics and Stability of Solder Powders in Aqueous Media

Authors: Terence Lucero F. Menor, Manolo G. Mena, Herman D. Mendoza

Abstract:

Solder pastes are widely used in creating mechanical, thermal and electrical connection between electronic components. Continued miniaturization of consumer electronics drives manufacturers to achieve smaller, lighter, and faster electronic packages at low cost. This faces them to the difficult challenge of dispensing solder pastes in extremely precise and repeatable manner. The most common problem in solder paste dispensing is the clogging of dispensers which results from agglomeration and settling of solder powders leading to increase on the effective particle size and uneven distribution of particles in the mixture. In this work, microelectrophoresis was employed to investigate the effect of pH and KNO₃ concentration on the electrokinetic behavior and stability of SAC305, PbSn5Ag2.5 and Sn powders in aqueous media. Results revealed that the electrokinetic behavior of the three types of solder powders are similar, which was attributed to high SnO₂ content on the surface of the particles. Electrokinetic measurements showed that the zeta potentials of the solder powders are highly dependent on pH and KNO₃ concentration with isoelectric points ranging from 3.5 to 5.5. Results were verified using stability tests.

Keywords: electrokinetic behavior, isoelectric point, solder powder, stability, surface analysis

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1674 Challenging Hegemonic Masculinity in Nigerian Hip Hop: An Evaluation of Gender Representation in Falz the Bahd Guy’s Moral Instruction Album

Authors: Adelaja O. Oriade

Abstract:

The Nigerian hip-hop music genre, like the African American scene where it was adopted from, is riddled with musical lyrics that amplify and normalize hypermasculinity, homophobia, sexism, and objectification of women. Several factors are responsible for this anomaly; however, the greatest factor is the urge of hip-hop musicians to achieve the commercial success that is dependent on selling records and appealing to the established societal accepted norm for hip-hop music. Consequently, this paper presents a counter-narrative of this gender representation within the Nigerian hip-hop industry. This study analyzed the musical lyrics of the ‘Hypocrisy’ track on the 2019 album of famous Nigerian rapper, Falz the Bahd Guy; and argued that Falz in this album challenged the predominant ideas of hegemonic masculinity by singing in favor of LGBT people and women. Also, based on the success of this album, this paper argues that a hip-hop album can achieve commercial success without aligning with predominant hip-hop parameters of gender representation. The study recommends that future studies should evaluate the reactions of Nigerians to these gender presentations by Falz the Bahd guy.

Keywords: hegemonic masculinity, hypermasculinity, LGBT, misogyny, sexism

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1673 The Effect of Energy Consumption and Losses on the Nigerian Manufacturing Sector: Evidence from the ARDL Approach

Authors: Okezie A. Ihugba

Abstract:

The bounds testing ARDL (2, 2, 2, 2, 0) technique to cointegration was used in this study to investigate the effect of energy consumption and energy loss on Nigeria's manufacturing sector from 1981 to 2020. The model was created to determine the relationship between these three variables while also accounting for interactions with control variables such as inflation and commercial bank loans to the manufacturing sector. When the dependent variables are energy consumption and energy loss, the bounds tests show that the variables of interest are bound together in the long run. Because electricity consumption is a critical factor in determining manufacturing value-added in Nigeria, some intriguing observations were made. According to the findings, the relationship between LELC and LMVA is statistically significant. According to the findings, electricity consumption reduces manufacturing value-added. The target variable (energy loss) is statistically significant and has a positive sign. In Nigeria, a 1% reduction in energy loss increases manufacturing value-added by 36% in the first lag and 35% in the second. According to the study, the government should speed up the ongoing renovation of existing power plants across the country, as well as the construction of new gas-fired power plants. This will address a number of issues, including overpricing of electricity as a result of grid failure.

Keywords: L60, Q43, H81, C52, E31, ARDL, cointegration, Nigeria's manufacturing

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1672 Thermal End Effect on the Isotachophoretic Separation of Analytes

Authors: Partha P. Gopmandal, S. Bhattacharyya

Abstract:

We investigate the thermal end effect on the pseudo-steady state behavior of the isotachophoretic transport of ionic species in a 2-D microchannel. Both ends of the channel are kept at a constant temperature which may lead to significant changes in electrophoretic migration speed. A mathematical model based on Nernst-Planck equations for transport of ions coupled with the equation for temperature field is considered. In addition, the charge conservation equations govern the potential field due to the external electric field. We have computed the equations for ion transport, potential and temperature in a coupled manner through the finite volume method. The diffusive terms are discretized via central difference scheme, while QUICK (Quadratic Upwind Interpolation Convection Kinematics) scheme is used to discretize the convective terms. We find that the thermal end effect has significant effect on the isotachophoretic (ITP) migration speed of the analyte. Our result shows that the ITP velocity for temperature dependent case no longer varies linearly with the applied electric field. A detailed analysis has been made to provide a range of the key parameters to minimize the Joule heating effect on ITP transport of analytes.

Keywords: finite volume method, isotachophoresis, QUICK scheme, thermal effect

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1671 The Role of Contextual Factors in the Sustainability Reporting of Australian and New Zealand Companies

Authors: Ramona Zharfpeykan

Abstract:

The concept of sustainability is generally considered as a key topic in many countries, and sustainability reporting is becoming an important tool for companies to communicate their sustainability plans and performance to their stakeholders. There have been various studies on factors that may influence sustainability reporting in companies. This study examines the possible effect of some of the organisational factors on corporate sustainability reporting. The organisational factors included in this study are a company’s type (public or private), industry, and size as well as managers’ perception of the level of importance of indicators in reporting these indicators. A survey was conducted from 240 Australian and New Zealand companies in various industries. They were asked about their perception of the importance of sustainability indicators in their performance and if they report these indicators. The GRI indicators used to develop the survey. A multiple regression model was developed using reporting strategy score as dependent and type, size, industry categorisation, and managers’ perception of the level of importance of the GRI indicators as independent factors. The results show that among all the factors included in the model, size of a company and the perception of managers of the level of importance of environmental and labour practice indicators can affect the sustainability scores of these companies.

Keywords: sustainability reporting, global reporting initiative, sustainability reporting strategy, organisational features

Procedia PDF Downloads 160
1670 Model Based Fault Diagnostic Approach for Limit Switches

Authors: Zafar Mahmood, Surayya Naz, Nazir Shah Khattak

Abstract:

The degree of freedom relates to our capability to observe or model the energy paths within the system. Higher the number of energy paths being modeled leaves to us a higher degree of freedom, but increasing the time and modeling complexity rendering it useless for today’s world’s need for minimum time to market. Since the number of residuals that can be uniquely isolated are dependent on the number of independent outputs of the system, increasing the number of sensors required. The examples of discrete position sensors that may be used to form an array include limit switches, Hall effect sensors, optical sensors, magnetic sensors, etc. Their mechanical design can usually be tailored to fit in the transitional path of an STME in a variety of mechanical configurations. The case studies into multi-sensor system were carried out and actual data from sensors is used to test this generic framework. It is being investigated, how the proper modeling of limit switches as timing sensors, could lead to unified and neutral residual space while keeping the implementation cost reasonably low.

Keywords: low-cost limit sensors, fault diagnostics, Single Throw Mechanical Equipment (STME), parameter estimation, parity-space

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1669 Computational Study of Chromatographic Behavior of a Series of S-Triazine Pesticides Based on Their in Silico Biological and Lipophilicity Descriptors

Authors: Lidija R. Jevrić, Sanja O. Podunavac-Kuzmanović, Strahinja Z. Kovačević

Abstract:

In this paper, quantitative structure-retention relationships (QSRR) analysis was applied in order to correlate in silico biological and lipophilicity molecular descriptors with retention values for the set of selected s-triazine herbicides. In silico generated biological and lipophilicity descriptors were discriminated using generalized pair correlation method (GPCM). According to this method, the significant difference between independent variables can be noticed regardless almost equal correlation with dependent variable. Using established multiple linear regression (MLR) models some biological characteristics could be predicted. Established MLR models were evaluated statistically and the most suitable models were selected and ranked using sum of ranking differences (SRD) method. In this method, as reference values, average experimentally obtained values are used. Additionally, using SRD method, similarities among investigated s-triazine herbicides can be noticed. These analysis were conducted in order to characterize selected s-triazine herbicides for future investigations regarding their biodegradability. This study is financially supported by COST action TD1305.

Keywords: descriptors, generalized pair correlation method, pesticides, sum of ranking differences

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1668 Dissipation of Tebuconazole in Cropland Soils as Affected by Soil Factors

Authors: Bipul Behari Saha, Sunil Kumar Singh, P. Padmaja, Kamlesh Vishwakarma

Abstract:

Dissipation study of tebuconazole in alluvial, black and deep-black clayey soils collected from paddy, mango and peanut cropland of tropical agro-climatic zone of India at three concentration levels were carried out for monitoring the water contamination through persisted residual toxicity. The soil-slurry samples were analyzed by capillary GC-NPD methods followed by ultrasound-assisted extraction (UAE) technique and cleanup process. An excellent linear relationship between peak area and concentration obtained in the range 1 to 50 μgkg-1. The detection (S/N, 3 ± 0.5) and quantification (S/N, 7.5 ± 2.5) limits were 3 and 10 μgkg-1 respectively. Well spiked recoveries were achieved from 96.28 to 99.33 % at levels 5 and 20 μgkg-1 and method precision (% RSD) was ≤ 5%. The soils dissipation of tebuconazole was fitted in first order kinetic-model with half-life between 34.48 to 48.13 days. The soil organic-carbon (SOC) content correlated well with the dissipation rate constants (DRC) of the fungicide Tebuconazole. An increase in the SOC content resulted in faster dissipation. The results indicate that the soil organic carbon and tebuconazole concentrations plays dominant role in dissipation processes. The initial concentration illustrated that the degradation rate of tebuconazole in soils was concentration dependent.

Keywords: cropland soil, dissipation, laboratory incubation, tebuconazole

Procedia PDF Downloads 253
1667 Cultural Environment, Behavior and Diabetes Melitus Incident in Urban Area of Semarang, Indonesia

Authors: Oktia Woro Kasmini Handayani, Sri Ratna Rahayu, Efa Nugroho, Berta Kalswahermawati

Abstract:

Diabetes occurs 10 years faster in the Southeast Asian region than the European region, which occurs in the most productive periods. Cultural differences as well as cultural transitions can be determinant factors of health cases in urban and rural areas. The purpose of this research is to analyze the effect of the cultural environment, behavior and the occurrence of diabetes mellitus in urban areas of Semarang, Indonesia. The research was conducted in the area of Semarang Regency, using a quantitative approach and supported by qualitative data, the population is DM type 2 patients, sample size of 200 people, with a purposive sampling technique. The independent variable consists of cultural environment, behavior, and the dependent variable is DM. The data is analyzed with regression test method. Cultural environment affects behavior positively, with t value of 4,690 and p (sig.) 0.000, this means sig <0.05, while the effect of behavior on Diabetes Mellitus obtained t value 2.950 with p-value (sig.) 0.003 this means that sig <0.05, thus it can be interpreted that the behavior has a significant effect on Diabetes Mellitus. The cultural environment directly affects the incidence of DM. It can also shape a person's behavior or lifestyle or habit, whether healthy or unhealthy one, which in turn causes symptoms of DM.

Keywords: Behavior, Cultural Environment, Diebetes Millitus, Urban

Procedia PDF Downloads 138
1666 Feasibility of Agro Waste-Derived Adsorbent for Colour Removal

Authors: U. P. L. Wijayarathne, P. W. Vidanage, H. K. D. Jayampath, K. W. P. M. Kothalawala

Abstract:

Feasibility of utilizing Empty Bunch (EB) fibre, a solid waste of palm oil extraction process, as an adsorbent is analysed in this study. Empty bunch fibre is generated after the extraction of retained oil in the sterilized and threshed empty fruit bunches. Besides the numerous characteristics of EB fibre, which enable its utilization as a fuel, a bio-composite material, or mulch, EB fibre also shows exceptional characteristics of a good adsorbent. Fixed bed adsorption method is used to study the adsorptivity of EB fibre using a continuous adsorption column with Methyl-blue (1.13ppm) as the feed. Adsorptivity is assumed to be solely dependent on the bed porosity keeping other parameters (feed flow rate, bed height, bed diameter, and operating temperature) constant. Bed porosity is changed by means of compact ratio and the variation of the feed concentration is analysed using a photometric method. Break through curves are plotted at different porosity levels and optimum bed porosity is identified for a given feed stream. Feasibility of using the EB fibre as an inexpensive and an abundant adsorbent in wastewater treatment facilities, where the effluent colour reduction is adamant, is also discussed.

Keywords: adsorption, fixed bed, break through time, methylene blue, oil palm fibre

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1665 Impact Deformation and Fracture Behaviour of Cobalt-Based Haynes 188 Superalloy

Authors: Woei-Shyan Lee, Hao-Chien Kao

Abstract:

The impact deformation and fracture behaviour of cobalt-based Haynes 188 superalloy are investigated by means of a split Hopkinson pressure bar. Impact tests are performed at strain rates ranging from 1×103 s-1 to 5×103 s-1 and temperatures between 25°C and 800°C. The experimental results indicate that the flow response and fracture characteristics of cobalt-based Haynes 188 superalloy are significantly dependent on the strain rate and temperature. The flow stress, work hardening rate and strain rate sensitivity all increase with increasing strain rate or decreasing temperature. It is shown that the impact response of the Haynes 188 specimens is adequately described by the Zerilli-Armstrong fcc model. The fracture analysis results indicate that the Haynes 188 specimens fail predominantly as the result of intensive localised shearing. Furthermore, it is shown that the flow localisation effect leads to the formation of adiabatic shear bands. The fracture surfaces of the deformed Haynes 188 specimens are characterised by dimple- and / or cleavage-like structure with knobby features. The knobby features are thought to be the result of a rise in the local temperature to a value greater than the melting point.

Keywords: Haynes 188 alloy, impact, strain rate and temperature effect, adiabatic shearing

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1664 Mechanism of Performance of Soil-Cement Columns under Shallow Foundations in Liquefiable Soil

Authors: Zaheer Ahmed Almani, Agha Faisal Habib Pathan, Aneel Kumar Hindu

Abstract:

In this study, the effects of ground reinforcement with stiff soil-cement columns on liquefiable ground and on the shallow foundation of structure were investigated. The modelling and analysis of shallow foundation of the structure founded on the composite reinforced ground were carried out with finite difference FLAC commercial software. The results showed that stiff columns were not effective to the redistribute the shear stresses in the composite ground, thus, were not effective to reduce shear stress and shear strain on the soil between the columns. The excessive pore pressure increase which is dependent on volumetric strain (contractive) tendency of loose sand upon shearing, was not reduced to a significant level that liquefaction potential could be remediated. Thus, mechanism of performance with reduction of pore pressure and consequent liquefaction was not predicted in numerical analysis. Nonetheless, the columns were effective to resist the load of structure in compression and reduced the liquefaction-induced large settlements of structure to tolerable limits when provided adjacent and beneath the pad of shallow foundation.

Keywords: earthquake, liquefaction, mechanism, soil-cement columns

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1663 The Effect of Institutions on Economic Growth: An Analysis Based on Bayesian Panel Data Estimation

Authors: Mohammad Anwar, Shah Waliullah

Abstract:

This study investigated panel data regression models. This paper used Bayesian and classical methods to study the impact of institutions on economic growth from data (1990-2014), especially in developing countries. Under the classical and Bayesian methodology, the two-panel data models were estimated, which are common effects and fixed effects. For the Bayesian approach, the prior information is used in this paper, and normal gamma prior is used for the panel data models. The analysis was done through WinBUGS14 software. The estimated results of the study showed that panel data models are valid models in Bayesian methodology. In the Bayesian approach, the effects of all independent variables were positively and significantly affected by the dependent variables. Based on the standard errors of all models, we must say that the fixed effect model is the best model in the Bayesian estimation of panel data models. Also, it was proved that the fixed effect model has the lowest value of standard error, as compared to other models.

Keywords: Bayesian approach, common effect, fixed effect, random effect, Dynamic Random Effect Model

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1662 Application of Principle Component Analysis for Classification of Random Doppler-Radar Targets during the Surveillance Operations

Authors: G. C. Tikkiwal, Mukesh Upadhyay

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During the surveillance operations at war or peace time, the Radar operator gets a scatter of targets over the screen. This may be a tracked vehicle like tank vis-à-vis T72, BMP etc, or it may be a wheeled vehicle like ALS, TATRA, 2.5Tonne, Shaktiman or moving army, moving convoys etc. The Radar operator selects one of the promising targets into Single Target Tracking (STT) mode. Once the target is locked, the operator gets a typical audible signal into his headphones. With reference to the gained experience and training over the time, the operator then identifies the random target. But this process is cumbersome and is solely dependent on the skills of the operator, thus may lead to misclassification of the object. In this paper we present a technique using mathematical and statistical methods like Fast Fourier Transformation (FFT) and Principal Component Analysis (PCA) to identify the random objects. The process of classification is based on transforming the audible signature of target into music octave-notes. The whole methodology is then automated by developing suitable software. This automation increases the efficiency of identification of the random target by reducing the chances of misclassification. This whole study is based on live data.

Keywords: radar target, fft, principal component analysis, eigenvector, octave-notes, dsp

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1661 A Comprehensive Evaluation of the Bus Rapid Transit Project from Gazipur to Airport at Dhaka Focusing on Environmental Impacts

Authors: Swapna Begum, Higano Yoshiro

Abstract:

Dhaka is the capital city of Bangladesh. It is considered as one of the traffic congested cities in the world. The growth of the population of this city is increasing day by day. The land use pattern and the increased socio-economic characteristics increase the motor vehicle ownership of this city. The rapid unplanned urbanization and poor transportation planning have deteriorated the transport environment of this city. Also, the huge travel demand with non-motorized traffics on streets is accounted for enormous traffic congestion in this city. The land transport sector in Dhaka is mainly dependent on road transport comprised of both motorized and non-motorized modes of travel. This improper modal mix and the un-integrated system have resulted in huge traffic congestion in this city. Moreover, this city has no well-organized public transport system and any Mass Transit System to cope with this ever increasing demand. Traffic congestion causes serious air pollution and adverse impact on the economy by deteriorating the accessibility, level of service, safety, comfort and operational efficiency. Therefore, there is an imperative need to introduce a well-organized, properly scheduled mass transit system like (Bus Rapid Transit) BRT minimizing the existing problems.

Keywords: air pollution, BRT, mass transit, traffic congestion

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1660 Free Vibration Characteristics of Nanoplates with Various Edge Supports Incorporating Surface Free Energy Effects

Authors: Saeid Sahmani

Abstract:

Due to size-dependent behavior of nanostrustures, the classical continuum models are not applicable for the analyses at this submicrion size. Surface stress effect is one of the most important matters which make the nanoscale structures to have different properties compared to the conventional structures due to high surface to volume ratio. In the present study, free vibration characteristics of nanoplates are investigated including surface stress effects. To this end, non-classical plate model based on Gurtin-Murdoch elasticity theory is proposed to evaluate the surface stress effects on the vibrational behavior of nanoplates subjected to different boundary conditions. Generalized differential quadrature (GDQ) method is employed to discretize the governing non-classical differential equations along with various edge supports. Selected numerical results are given to demonstrate the distinction between the behavior of nanoplates predicted by the classical and present non-classical plate models that leads to illustrate the great influence of surface stress effect. It is observed that this influence quite depends on the magnitude of the surface elastic constants which are relevant to the selected material.

Keywords: nanomechanics, surface stress, free vibration, GDQ method, small scale effect

Procedia PDF Downloads 358
1659 The effect of Reflective Thinking on Iranian EFL Learners’ Language Learning Strategy Use, L2 Proficiency, and Beliefs about Second Language Learning and Teaching

Authors: Mohammad Hadi Mahmoodi, Mojtaba Farahani

Abstract:

The present study aimed at investigating whether reflective thinking differentiates Iranian EFL learners regarding language learning strategy use, beliefs about language learning and teaching, and L2 proficiency. To this end, the researcher adopted a mixed method approach. First, 94 EFL learners were asked to complete Reflective Thinking Questionnaire (Kember et al., 2000), Beliefs about Language Learning and Teaching Inventory (Horwitz, 1985), Strategy Inventory for Language Learning (Oxford, 1990), and Oxford Quick Placement Test. The results of three separate one-way ANOVAs indicated that reflective thinking significantly differentiates Iranian EFL learners concerning: (a)language learning strategy use, (b) beliefs about language learning and teaching, and (c) general language proficiency. Furthermore, to see where the differences lay, three separate post-hoc Tukey tests were run the results of which showed that learners with different levels of reflectivity (high, mid, and low) were significantly different from each other in all three dependent variables. Finally, to increase the validity of the findings thirty of the participants were interviewed and the results were analyzed through template organizing style method (Crabtree & Miller, 1999). The results of the interview analysis supported the results of quantitative data analysis.

Keywords: reflective thinking, language learning strategy use, beliefs toward language learning and teaching

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1658 Relevance of Dosing Time for Everolimus Toxicity in Respect to the Circadian P-Glycoprotein Expression in Mdr1a::Luc Mice

Authors: Narin Ozturk, Xiao-Mei Li, Sylvie Giachetti, Francis Levi, Alper Okyar

Abstract:

P-glycoprotein (P-gp, MDR1, ABCB1) is a transmembrane protein acting as an ATP-dependent efflux pump and functions as a biological barrier by extruding drugs and xenobiotics out of cells in healthy tissues especially in intestines, liver and brain as well as in tumor cells. The circadian timing system controls a variety of biological functions in mammals including xenobiotic metabolism and detoxification, proliferation and cell cycle events, and may affect pharmacokinetics, toxicity and efficacy of drugs. Selective mTOR (mammalian target of rapamycin) inhibitor everolimus is an immunosuppressant and anticancer drug that is active against many cancers, and its pharmacokinetics depend on P-gp. The aim of this study was to investigate the dosing time-dependent toxicity of everolimus with respect to the intestinal P-gp expression rhythms in mdr1a::Luc mice using Real Time-Biolumicorder (RT-BIO) System. Mdr1a::Luc male mice were synchronized with 12 h of Light and 12 h of Dark (LD12:12, with Zeitgeber Time 0 – ZT0 – corresponding Light onset). After 1-week baseline recordings, everolimus (5 mg/kg/day x 14 days) was administered orally at ZT1-resting period- and ZT13-activity period- to mdr1a::Luc mice singly housed in an innovative monitoring device, Real Time-Biolumicorder units which let us monitor real-time and long-term gene expression in freely moving mice. D-luciferin (1.5 mg/mL) was dissolved in drinking water. Mouse intestinal mdr1a::Luc oscillation profile reflecting P-gp gene expression and locomotor activity pattern were recorded every minute with the photomultiplier tube and infrared sensor respectively. General behavior and clinical signs were monitored, and body weight was measured every day as an index of toxicity. Drug-induced body weight change was expressed relative to body weight on the initial treatment day. Statistical significance of differences between groups was validated with ANOVA. Circadian rhythms were validated with Cosinor Analysis. Everolimus toxicity changed as a function of drug timing, which was least following dosing at ZT13, near the onset of the activity span in male mice. Mean body weight loss was nearly twice as large in mice treated with 5 mg/kg everolimus at ZT1 as compared to ZT13 (8.9% vs. 5.4%; ANOVA, p < 0.001). Based on the body weight loss and clinical signs upon everolimus treatment, tolerability for the drug was best following dosing at ZT13. Both rest-activity and mdr1a::Luc expression displayed stable 24-h periodic rhythms before everolimus and in both vehicle-treated controls. Real-time bioluminescence pattern of mdr1a revealed a circadian rhythm with a 24-h period with an acrophase at ZT16 (Cosinor, p < 0.001). Mdr1a expression remained rhythmic in everolimus-treated mice, whereas down-regulation was observed in P-gp expression in 2 of 4 mice. The study identified the circadian pattern of intestinal P-gp expression with an unprecedented precision. The circadian timing depending on the P-gp expression rhythms may play a crucial role in the tolerability/toxicity of everolimus. The circadian changes in mdr1a genes deserve further studies regarding their relevance for in vitro and in vivo chronotolerance of mdr1a-transported anticancer drugs. Chronotherapy with P-gp-effluxed anticancer drugs could then be applied according to their rhythmic patterns in host and tumor to jointly maximize treatment efficacy and minimize toxicity.

Keywords: circadian rhythm, chronotoxicity, everolimus, mdr1a::Luc mice, p-glycoprotein

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1657 The Influences of Accountants’ Potential Performance on Their Working Process: Government Savings Bank, Northeast, Thailand

Authors: Prateep Wajeetongratana

Abstract:

The purpose of this research was to study the influence of accountants’ potential performance on their working process, a case study of Government Savings Banks in the northeast of Thailand. The independent variables included accounting knowledge, accounting skill, accounting value, accounting ethics, and accounting attitude, while the dependent variable included the success of the working process. A total of 155 accountants working for Government Savings Banks were selected by random sampling. A questionnaire was used as a tool for collecting data. Descriptive statistics in this research included percentage, mean, and multiple regression analyses. The findings revealed that the majority of accountants were female with an age between 35-40 years old. Most of the respondents had an undergraduate degree with ten years of experience. Moreover, the factors of accounting knowledge, accounting skill, accounting a value and accounting ethics and accounting attitude were rated at a high level. The findings from regression analysis of observation data revealed a causal relationship in that the observation data could explain at least 51 percent of the success in the accountants’ working process.

Keywords: influence, potential performance, success, working process

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1656 Municipal Solid Waste Generation Trend in the Metropolitan Cities of the Muslim World

Authors: Farzaneh Fakheri Raof, Abdolkhalegh vadian

Abstract:

One of the most important environmental issues in developing countries is municipal solid waste management. In this context, knowledge of the quantity and composition of solid waste provides the basic information for the optimal management of solid waste. Many studies have been conducted to investigate the impact of economic, social and cultural factors on generation trend of solid waste, however, few of these have addressed the role of religion in the matter. The present study is a field investigation on generation trend of solid waste in Mashhad, a metropolitan city in northeastern Iran. Accordingly, the religious rituals, quantity and composition of municipal solid waste were considered as independent and dependent variables, respectively. For this purpose, the quantity of the solid waste was initially determined. Afterwards, they were classified into 12 groups using the relevant standard methods. The results showed that the production rate of the municipal solid waste was 1,507 tons per day. Composing 65.2% of the whole; the organic materials constitute the largest share of the total municipal solid waste in Mashhad. The obtained results also revealed that there is a positive relationship between waste generation and the months of religious ceremonies so that the greatest amount of waste generated in the city was reported from Ramadan (as a religious month) in a way that it was significantly different from other months.

Keywords: Mashhad, municipal solid waste, religious months, waste composition, organic waste

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1655 Functional Poly(Hedral Oligomeric Silsesquioxane) Nano-Spacer to Boost Quantum Resistive Vapour Sensors’ Sensitivity and Selectivity

Authors: Jean-Francois Feller

Abstract:

The analysis of the volatolome emitted by the human body with a sensor array (e-nose) is a method for clinical applications full of promises to make an olfactive fingerprint characteristic of people's health state. But the amount of volatile organic compounds (VOC) to detect, being in the range of parts per billion (ppb), and their diversity (several hundred) justifies developing ever more sensitive and selective vapor sensors to improve the discrimination ability of the e-nose, is still of interest. Quantum resistive vapour sensors (vQRS) made with nanostructured conductive polymer nanocomposite transducers have shown a great versatility in both their fabrication and operation to detect volatiles of interest such as cancer biomarkers. However, it has been shown that their chemo-resistive response was highly dependent on the quality of the inter-particular junctions in the percolated architecture. The present work investigates the effectiveness of poly(hedral oligomeric silsesquioxane) acting as a nanospacer to amplify the disconnectability of the conducting network and thus maximize the vQRS's sensitivity to VOC.

Keywords: volatolome, quantum resistive vapour sensor, nanostructured conductive polymer nanocomposites, olfactive diagnosis

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