Search results for: level set method
Commenced in January 2007
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Edition: International
Paper Count: 28544

Search results for: level set method

22154 Fuzzy Optimization Multi-Objective Clustering Ensemble Model for Multi-Source Data Analysis

Authors: C. B. Le, V. N. Pham

Abstract:

In modern data analysis, multi-source data appears more and more in real applications. Multi-source data clustering has emerged as a important issue in the data mining and machine learning community. Different data sources provide information about different data. Therefore, multi-source data linking is essential to improve clustering performance. However, in practice multi-source data is often heterogeneous, uncertain, and large. This issue is considered a major challenge from multi-source data. Ensemble is a versatile machine learning model in which learning techniques can work in parallel, with big data. Clustering ensemble has been shown to outperform any standard clustering algorithm in terms of accuracy and robustness. However, most of the traditional clustering ensemble approaches are based on single-objective function and single-source data. This paper proposes a new clustering ensemble method for multi-source data analysis. The fuzzy optimized multi-objective clustering ensemble method is called FOMOCE. Firstly, a clustering ensemble mathematical model based on the structure of multi-objective clustering function, multi-source data, and dark knowledge is introduced. Then, rules for extracting dark knowledge from the input data, clustering algorithms, and base clusterings are designed and applied. Finally, a clustering ensemble algorithm is proposed for multi-source data analysis. The experiments were performed on the standard sample data set. The experimental results demonstrate the superior performance of the FOMOCE method compared to the existing clustering ensemble methods and multi-source clustering methods.

Keywords: clustering ensemble, multi-source, multi-objective, fuzzy clustering

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22153 Comparison of Tensile Strength and Folding Endurance of (FDM Process) 3D Printed ABS and PLA Materials

Authors: R. Devicharan

Abstract:

In a short span 3D Printing is expected to play a vital role in our life. The possibility of creativity and speed in manufacturing through various 3D printing processes is infinite. This study is performed on the FDM (Fused Deposition Modelling) method of 3D printing, which is one of the pre-dominant methods of 3D printing technologies. This study focuses on physical properties of the objects produced by 3D printing which determine the applications of the 3D printed objects. This paper specifically aims at the study of the tensile strength and the folding endurance of the 3D printed objects through the FDM (Fused Deposition Modelling) method using the ABS (Acronitirile Butadiene Styrene) and PLA (Poly Lactic Acid) plastic materials. The study is performed on a controlled environment and the specific machine settings. Appropriate tables, graphs are plotted and research analysis techniques will be utilized to analyse, verify and validate the experiment results.

Keywords: FDM process, 3D printing, ABS for 3D printing, PLA for 3D printing, rapid prototyping

Procedia PDF Downloads 589
22152 Structural and Magnetic Properties of CoFe2O4:Nd3+/Dy3+/Pr3+/Gd3+ Nanoparticles Synthesized by Starch-Assisted Sol-Gel Auto-Combustion Method and Annealing Effect

Authors: Raghvendra Singh Yadav, Ivo Kuřitka, Jaromir Havlica, Zuzana Kozakova, Jiri Masilko, Lukas Kalina, Miroslava Hajdúchová, Vojtěch Enev, Jaromir Wasserbauer

Abstract:

In this work, we investigated the structural and magnetic properties of CoFe2O4:Nd3+/Dy3+/Pr3+/Gd3+ nanoparticles synthesized by starch-assisted sol-gel combustion method. X-ray diffraction pattern confirmed the formation of cubic spinel structure of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) doped CoFe2O4 spinel ferrite nanoparticles. Raman and Fourier Transform Infrared spectroscopy study also confirmed cubic spinel structure of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles. The field emission scanning electron microscopy study revealed the effect of annealing temperature on size of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles and particles were in the range of 10-100 nm. The magnetic properties of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles were investigated by using vibrating sample magnetometer. The variation in saturation magnetization, coercivity and remanent magnetization with annealing temperature/ particle size of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles was observed. Acknowledgment: This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic – Program NPU I (LO1504).

Keywords: starch, sol-gel combustion method, rare-earth ions, spinel ferrite nanoparticles, magnetic properties

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22151 Optimization of the Drinking Water Treatment Process

Authors: M. Farhaoui, M. Derraz

Abstract:

Problem statement: In the water treatment processes, the coagulation and flocculation processes produce sludge according to the level of the water turbidity. The aluminum sulfate is the most common coagulant used in water treatment plants of Morocco as well as many countries. It is difficult to manage the sludge produced by the treatment plant. However, it can be used in the process to improve the quality of the treated water and reduce the aluminum sulfate dose. Approach: In this study, the effectiveness of sludge was evaluated at different turbidity levels (low, medium, and high turbidity) and coagulant dosage to find optimal operational conditions. The influence of settling time was also studied. A set of jar test experiments was conducted to find the sludge and aluminum sulfate dosages in order to improve the produced water quality for different turbidity levels. Results: Results demonstrated that using sludge produced by the treatment plant can improve the quality of the produced water and reduce the aluminum sulfate using. The aluminum sulfate dosage can be reduced from 40 to 50% according to the turbidity level (10, 20 and 40 NTU). Conclusions/Recommendations: Results show that sludge can be used in order to reduce the aluminum sulfate dosage and improve the quality of treated water. The highest turbidity removal efficiency is observed within 6 mg/l of aluminum sulfate and 35 mg/l of sludge in low turbidity, 20 mg/l of aluminum sulfate and 50 mg/l of sludge in medium turbidity and 20 mg/l of aluminum sulfate and 60 mg/l of sludge in high turbidity. The turbidity removal efficiency is 97.56%, 98.96% and 99.47% respectively for low, medium and high turbidity levels.

Keywords: coagulation process, coagulant dose, sludge, turbidity removal

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22150 Calibration of Site Effect Parameters in the GMPM BSSA 14 for the Region of Spain

Authors: Gonzalez Carlos, Martinez Fransisco

Abstract:

The creation of a seismic prediction model that considers all the regional variations and perfectly adjusts its results to the response spectra is very complicated. To achieve statistically acceptable results, it is necessary to process a sufficiently robust data set, and even if high efficiencies are achieved, this model will only work properly in this region. However, when using it in other regions, differences are found due to different parameters that have not been calibrated to other regions, such as the site effect. The fact that impedance contrasts, as well as other factors belonging to the site, have a great influence on the local response is well known, which is why this work, using the residual method, is intended to establish a regional calibration of the corresponding parameters site effect for the Spain region in the global GMPM BSSA 14.

Keywords: GMPM, seismic prediction equations, residual method, response spectra, impedance contrast

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22149 Awareness regarding Radiation Protection among the Technicians Practicing in Bharatpur, Chitwan, Nepal

Authors: Jayanti Gyawali, Deepak Adhikari, Mukesh Mallik, Sanjay Sah

Abstract:

Radiation is defined as an emission or transmission of energy in form of waves or particles through space or material medium. The major imaging tools used in diagnostic radiology is based on the use of ionizing radiation. A cross-sectional study was carried out during July- August, 2015 among technicians in 15 different hospitals of Bharatpur, Chitwan, Nepal to assess awareness regarding radiation protection and their current practice. The researcher was directly engaged for data collection using self-administered semi-structured questionnaire. The findings of the study are presented in socio-demographic characteristics of respondents, current practice of respondents and knowledge regarding radiation protection. The result of this study demonstrated that despite the importance of radiation and its consequent hazards, the level of knowledge among technicians is only 60.23% and their current practice is 76.84%. The difference in the mean score of knowledge and practice might have resulted due to technicians’s regular work and lack of updates. The study also revealed that there is no significant (p>0.05) difference in knowledge level of technicians practicing in different hospitals. But the mean difference in practice scores of different hospital is significant (p<0.05) i.e. i.e. the cancer hospital with large volumes of regular radiological cases and radiation therapies for cancer treatment has better practice in comparison to other hospitals. The deficiency in knowledge of technicians might alter the expected benefits, compared to the risk involved, and can cause erroneous medical diagnosis and radiation hazard. Therefore, this study emphasizes the need for all technicians to update themselves with the appropriate knowledge and current practice about ionizing and non-ionizing radiation.

Keywords: technicians, knowledge, Nepal, radiation

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22148 Tunable Graphene Metasurface Modeling Using the Method of Moment Combined with Generalised Equivalent Circuit

Authors: Imen Soltani, Takoua Soltani, Taoufik Aguili

Abstract:

Metamaterials crossover classic physical boundaries and gives rise to new phenomena and applications in the domain of beam steering and shaping. Where electromagnetic near and far field manipulations were achieved in an accurate manner. In this sense, 3D imaging is one of the beneficiaries and in particular Denis Gabor’s invention: holography. But, the major difficulty here is the lack of a suitable recording medium. So some enhancements were essential, where the 2D version of bulk metamaterials have been introduced the so-called metasurface. This new class of interfaces simplifies the problem of recording medium with the capability of tuning the phase, amplitude, and polarization at a given frequency. In order to achieve an intelligible wavefront control, the electromagnetic properties of the metasurface should be optimized by means of solving Maxwell’s equations. In this context, integral methods are emerging as an important method to study electromagnetic from microwave to optical frequencies. The method of moment presents an accurate solution to reduce the problem of dimensions by writing its boundary conditions in the form of integral equations. But solving this kind of equations tends to be more complicated and time-consuming as the structural complexity increases. Here, the use of equivalent circuit’s method exhibits the most scalable experience to develop an integral method formulation. In fact, for allaying the resolution of Maxwell’s equations, the method of Generalised Equivalent Circuit was proposed to convey the resolution from the domain of integral equations to the domain of equivalent circuits. In point of fact, this technique consists in creating an electric image of the studied structure using discontinuity plan paradigm and taken into account its environment. So that, the electromagnetic state of the discontinuity plan is described by generalised test functions which are modelled by virtual sources not storing energy. The environmental effects are included by the use of an impedance or admittance operator. Here, we propose a tunable metasurface composed of graphene-based elements which combine the advantages of reflectarrays concept and graphene as a pillar constituent element at Terahertz frequencies. The metasurface’s building block consists of a thin gold film, a dielectric spacer SiO₂ and graphene patch antenna. Our electromagnetic analysis is based on the method of moment combined with generalised equivalent circuit (MoM-GEC). We begin by restricting our attention to study the effects of varying graphene’s chemical potential on the unit cell input impedance. So, it was found that the variation of complex conductivity of graphene allows controlling the phase and amplitude of the reflection coefficient at each element of the array. From the results obtained here, we were able to determine that the phase modulation is realized by adjusting graphene’s complex conductivity. This modulation is a viable solution compared to tunning the phase by varying the antenna length because it offers a full 2π reflection phase control.

Keywords: graphene, method of moment combined with generalised equivalent circuit, reconfigurable metasurface, reflectarray, terahertz domain

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22147 Amelioration of Over-Expression of bax, Nrf2 and NFК–β in Nano-Sized Titanium Dioxide-Intoxicated Mice by Potent Antioxidants

Authors: Maha Z. Rizk, Sami A. Fattah, Heba M. Darwish, Sanaa A. Ali, Mai O. Kadry

Abstract:

The increasing use of nanomaterials in consumer and industrial products has aroused global concern regarding their fate in biological systems resulting in demand for parallel risk assessment. The objective of this study is investigating either the effect of individual or combined doses of idebenone, carnosine and vitamin E on amelioration of some biochemical indices of nano sized titanium dioxide (TiO2 NPS) induced metabolic disorders in mice liver. TiO2-NPS was administered in an oral dose of 150 mg/kg for consecutive 14 days followed by oral daily doses of the aforementioned antioxidants for 1 month. TiO2-NPS induced a significant elevation in serum level of ALT and AST, hepatic inflammatory markers (tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)) and increased the percent of DNA damage which was assessed by COMET assay in addition to the apoptotic marker Caspase-3. Moreover, mRNA gene expression observed by RT-PCR showed a significant overexpression in nuclear factor relation-2 (Nrf2), nuclear factor kappa beta (NF-Kβ) and the apoptotic factor (bax), and a significant down-regulation in the antiapoptotic factor (bcl2) level. In conclusion, idebenone, carnosine and vitamin E ameliorated the deviated parameters with a variable degree with the most pronounced role in alleviating the hazardous effect of TiO2 NPS toxicity following the combination regimen.

Keywords: idebenone, carnosine, vitamin E, TiO2 NPS, caspase-3, NrF2, NF-KB

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22146 Design of Wide-Range Variable Fractional-Delay FIR Digital Filters

Authors: Jong-Jy Shyu, Soo-Chang Pei, Yun-Da Huang

Abstract:

In this paper, design of wide-range variable fractional-delay (WR-VFD) finite impulse response (FIR) digital filters is proposed. With respect to the conventional VFD filter which is designed such that its delay is adjustable within one unit, the proposed VFD FIR filter is designed such that its delay can be tunable within a wider range. By the traces of coefficients of the fractional-delay FIR filter, it is found that the conventional method of polynomial substitution for filter coefficients no longer satisfies the design demand, and the circuits perform the sinc function (sinc converter) are added to overcome this problem. In this paper, least-squares method is adopted to design WR-VFD FIR filter. Throughout this paper, several examples will be proposed to demonstrate the effectiveness of the presented methods.

Keywords: digital filter, FIR filter, variable fractional-delay (VFD) filter, least-squares approximation

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22145 Mobile Agents-Based Framework for Dynamic Resource Allocation in Cloud Computing

Authors: Safia Rabaaoui, Héla Hachicha, Ezzeddine Zagrouba

Abstract:

Nowadays, cloud computing is becoming the more popular technology to various companies and consumers, which benefit from its increased efficiency, cost optimization, data security, unlimited storage capacity, etc. One of the biggest challenges of cloud computing is resource allocation. Its efficiency directly influences the performance of the whole cloud environment. Finding an effective method to address these critical issues and increase cloud performance was necessary. This paper proposes a mobile agents-based framework for dynamic resource allocation in cloud computing to minimize both the cost of using virtual machines and the makespan. Furthermore, its impact on the best response time and power consumption has been studied. The simulation showed that our method gave better results than here.

Keywords: cloud computing, multi-agent system, mobile agent, dynamic resource allocation, cost, makespan

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22144 An Optimal Control Method for Reconstruction of Topography in Dam-Break Flows

Authors: Alia Alghosoun, Nabil El Moçayd, Mohammed Seaid

Abstract:

Modeling dam-break flows over non-flat beds requires an accurate representation of the topography which is the main source of uncertainty in the model. Therefore, developing robust and accurate techniques for reconstructing topography in this class of problems would reduce the uncertainty in the flow system. In many hydraulic applications, experimental techniques have been widely used to measure the bed topography. In practice, experimental work in hydraulics may be very demanding in both time and cost. Meanwhile, computational hydraulics have served as an alternative for laboratory and field experiments. Unlike the forward problem, the inverse problem is used to identify the bed parameters from the given experimental data. In this case, the shallow water equations used for modeling the hydraulics need to be rearranged in a way that the model parameters can be evaluated from measured data. However, this approach is not always possible and it suffers from stability restrictions. In the present work, we propose an adaptive optimal control technique to numerically identify the underlying bed topography from a given set of free-surface observation data. In this approach, a minimization function is defined to iteratively determine the model parameters. The proposed technique can be interpreted as a fractional-stage scheme. In the first stage, the forward problem is solved to determine the measurable parameters from known data. In the second stage, the adaptive control Ensemble Kalman Filter is implemented to combine the optimality of observation data in order to obtain the accurate estimation of the topography. The main features of this method are on one hand, the ability to solve for different complex geometries with no need for any rearrangements in the original model to rewrite it in an explicit form. On the other hand, its achievement of strong stability for simulations of flows in different regimes containing shocks or discontinuities over any geometry. Numerical results are presented for a dam-break flow problem over non-flat bed using different solvers for the shallow water equations. The robustness of the proposed method is investigated using different numbers of loops, sensitivity parameters, initial samples and location of observations. The obtained results demonstrate high reliability and accuracy of the proposed techniques.

Keywords: erodible beds, finite element method, finite volume method, nonlinear elasticity, shallow water equations, stresses in soil

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22143 Improving Second Language Speaking Skills via Video Exchange

Authors: Nami Takase

Abstract:

Computer-mediated-communication allows people to connect and interact with each other as if they were sharing the same space. The current study examined the effects of using video letters (VLs) on the development of second language speaking skills of Common European Framework of Reference for Languages (CEFR) A1 and CEFR B2 level learners of English as a foreign language. Two groups were formed to measure the impact of VLs. The experimental and control groups were given the same topic, and both groups worked with a native English-speaking university student from the United States of America. Students in the experimental group exchanged VLs, and students in the control group used video conferencing. Pre- and post-tests were conducted to examine the effects of each practice mode. The transcribed speech-text data showed that the VL group had improved speech accuracy scores, while the video conferencing group had increased sentence complexity scores. The use of VLs may be more effective for beginner-level learners because they are able to notice their own errors and replay videos to better understand the native speaker’s speech at their own pace. Both the VL and video conferencing groups provided positive feedback regarding their interactions with native speakers. The results showed how different types of computer-mediated communication impacts different areas of language learning and speaking practice and how each of these types of online communication tool is suited to different teaching objectives.

Keywords: computer-assisted-language-learning, computer-mediated-communication, english as a foreign language, speaking

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22142 Energy Performance of Buildings Due to Downscaled Seasonal Models

Authors: Anastasia K. Eleftheriadou, Athanasios Sfetsos, Nikolaos Gounaris

Abstract:

The present work examines the suitability of a seasonal forecasting model downscaled with a very high spatial resolution in order to assess the energy performance and requirements of buildings. The application of the developed model is applied on Greece for a period and with a forecast horizon of 5 months in the future. Greece, as a country in the middle of a financial crisis and facing serious societal challenges, is also very sensitive to climate changes. The commonly used method for the correlation of climate change with the buildings energy consumption is the concept of Degree Days (DD). This method can be applied to heating and cooling systems for a better management of environmental, economic and energy crisis, and can be used as medium (3-6 months) planning tools in order to predict the building needs and country’s requirements for residential energy use.

Keywords: downscaled seasonal models, degree days, energy performance

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22141 Investigating the Relationship between Service Quality and Amount of Violations in Community Pharmacies with Their Type of Ownership

Authors: Afshin Azari, Farzad Peiravian, Nazila Yousefi

Abstract:

Introduction: Community pharmacies have been always played an important role in public health. Therefore, having a decent service provided by these pharmacies is of paramount importance for the healthcare system. The issue of pharmacy ownership and its possible impact on the quality of services and amount of violations has been argued for many years, and there are different opinions around this debate. Since, so far, no scientific research has been performed to investigate this issue in Iran, this study aimed to examine the differences between these two types of pharmacies ownership in terms of violations and service quality. Method: This study investigates the impact of two different kinds of pharmacy ownership (pharmacists and non-pharmacist’s ownership) on the pharmacies’ amount of violations and services quality. Pharmacies’ amount of violations was examined using “pharmacy inspection reports” between September 2018 and September 2019, in their distinguishable categories: minor, major and critical violations. Then, service quality was examined using a questionnaire from the perspective of pharmacy customers. Results: Considering violations, there was no evidence to prove a significant relationship between critical violations and major violations with the type of pharmacy ownership. However, in minor violations, the average of violations was higher in pharmacies owned by pharmacists in comparison to their non-pharmacist owned counterparts. Regarding service quality, the results showed that there is no significant relationship between the quality of service and the type of pharmacy ownership. Discussion and Conclusion: In this study, no significant relationship was found between the amount of violations and the type of pharmacy ownership. This could indicate that the pharmacy ownership would not influence the rate of violations. Considering that more inspections have been carried out in non-pharmacist owned pharmacies, it can be concluded that these pharmacies are more under control, and in fact, this monitoring has reduced violations in these pharmacies. The quality of services in the two types of pharmacies were not significantly different from each other, and this shows that non-pharmacist-owned pharmacies also try to maintain the desired level of service in competition with their competitors.

Keywords: pharmacy ownership, quality of service, violation, community pharmacy

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22140 The History of Sambipitu Formation Temperature during the Early Miocene Epooch at Kali Ngalang, Nglipar, Gunung Kidul Regency

Authors: R. Harman Dwi, Ryan Avirsa, P. Abraham Ivan

Abstract:

Understanding of temperatures in the past, present, and future temperatures can be possible to do by analysis abundance of fossil foraminifera. This research was conducted in Sambipitu Formation, Ngalang River, Nglipar, Gunung Kidul Regency. The research method is divided into 3 stages: 1) study of literature, research based on previous researchers, 2) spatial, observation and sampling every 5-10 meters, 3) descriptive, analyzing samples consisting of a 10-gram sample weight, washing sample using 30% peroxide, biostratigraphy analysis, paleotemperature analysis using abundance of fossil, diversity analysis using Simpson diversity index method, and comparing current temperature data. There are two phases based on the appearance of Globorotalia menardii and Pulleniatina obliqueculata pointed to Phase Tropical Area, and the appearance of fossil Globigerinoides ruber and Orbulina universa fossil shows the phase of Subtropical Area. Paleotemperatur based on the appearance of Globorotalia menardii, Globigerinoides trilobus, Globigerinoides ruber, Orbulina universa, and Pulleniatina obliqueculata pointed to Warm Water Area and Warm Water Area (average surface water approximate 25°C).

Keywords: abundance, biostratigraphy, Simpson diversity index method, paleotemperature

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22139 Voluntary Work Monetary Value and Cost-Benefit Analysis with 'Value Audit and Voluntary Investment' Technique: Case Study of Yazd Red Crescent Society Youth Members Voluntary Work in Health and Safety Plan for New Year's Passengers

Authors: Hamed Seddighi Khavidak

Abstract:

Voluntary work has a lot of economic and social benefits for a country, but the economic value is ignored because it is voluntary. The aim of this study is reviewing Monetary Value of Voluntary Work methods and comparing opportunity cost method and replacement cost method both in theory and in practice. Beside monetary value, in this study, we discuss cost-benefit analysis of health and safety plan in the New Year that conducted by young volunteers of Red Crescent society of Iran. Method: We discussed eight methods for monetary value of voluntary work including: Alternative-Employment Wage Approach, Leisure-Adjusted OCA, Volunteer Judgment OCA, Replacement Wage Approach, Volunteer Judgment RWA, Supervisor Judgment RWA, Cost of Counterpart Goods and Services and Beneficiary Judgment. Also, for cost benefit analysis we drew on 'value audit and volunteer investment' (VIVA) technique that is used widely in voluntary organizations like international federation of Red Cross and Red Crescent societies. Findings: In this study, using replacement cost approach, voluntary work by 1034 youth volunteers was valued 938000000 Riyals and using Replacement Wage Approach it was valued 2268713232 Riyals. Moreover, Yazd Red Crescent Society spent 212800000 Riyals on food and other costs for these volunteers. Discussion and conclusion: In this study, using cost benefit analysis method that is Volunteer Investment and Value Audit (VIVA), VIVA rate showed that for every Riyal that the Red Crescent Society invested in the health and safety of New Year's travelers in its volunteer project, four Riyals returned, and using the wage replacement approach, 11 Riyals returned. Therefore, New Year's travelers health and safety project were successful and economically, it was worthwhile for the Red Crescent Society because the output was much bigger than the input costs.

Keywords: voluntary work, monetary value, youth, red crescent society

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22138 Uncertainty Quantification of Crack Widths and Crack Spacing in Reinforced Concrete

Authors: Marcel Meinhardt, Manfred Keuser, Thomas Braml

Abstract:

Cracking of reinforced concrete is a complex phenomenon induced by direct loads or restraints affecting reinforced concrete structures as soon as the tensile strength of the concrete is exceeded. Hence it is important to predict where cracks will be located and how they will propagate. The bond theory and the crack formulas in the actual design codes, for example, DIN EN 1992-1-1, are all based on the assumption that the reinforcement bars are embedded in homogeneous concrete without taking into account the influence of transverse reinforcement and the real stress situation. However, it can often be observed that real structures such as walls, slabs or beams show a crack spacing that is orientated to the transverse reinforcement bars or to the stirrups. In most Finite Element Analysis studies, the smeared crack approach is used for crack prediction. The disadvantage of this model is that the typical strain localization of a crack on element level can’t be seen. The crack propagation in concrete is a discontinuous process characterized by different factors such as the initial random distribution of defects or the scatter of material properties. Such behavior presupposes the elaboration of adequate models and methods of simulation because traditional mechanical approaches deal mainly with average material parameters. This paper concerned with the modelling of the initiation and the propagation of cracks in reinforced concrete structures considering the influence of transverse reinforcement and the real stress distribution in reinforced concrete (R/C) beams/plates in bending action. Therefore, a parameter study was carried out to investigate: (I) the influence of the transversal reinforcement to the stress distribution in concrete in bending mode and (II) the crack initiation in dependence of the diameter and distance of the transversal reinforcement to each other. The numerical investigations on the crack initiation and propagation were carried out with a 2D reinforced concrete structure subjected to quasi static loading and given boundary conditions. To model the uncertainty in the tensile strength of concrete in the Finite Element Analysis correlated normally and lognormally distributed random filed with different correlation lengths were generated. The paper also presents and discuss different methods to generate random fields, e.g. the Covariance Matrix Decomposition Method. For all computations, a plastic constitutive law with softening was used to model the crack initiation and the damage of the concrete in tension. It was found that the distributions of crack spacing and crack widths are highly dependent of the used random field. These distributions are validated to experimental studies on R/C panels which were carried out at the Laboratory for Structural Engineering at the University of the German Armed Forces in Munich. Also, a recommendation for parameters of the random field for realistic modelling the uncertainty of the tensile strength is given. The aim of this research was to show a method in which the localization of strains and cracks as well as the influence of transverse reinforcement on the crack initiation and propagation in Finite Element Analysis can be seen.

Keywords: crack initiation, crack modelling, crack propagation, cracks, numerical simulation, random fields, reinforced concrete, stochastic

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22137 Modelling and Simulation of Biomass Pyrolysis

Authors: P. Ahuja, K. S. S. Sai Krishna

Abstract:

There is a concern over the energy shortage in the modern societies as it is one of the primary necessities. Renewable energy, mainly biomass, is found to be one feasible solution as it is inexhaustible and clean energy source all over the world. Out of various methods, thermo chemical conversion is considered to be the most common and convenient method to extract energy from biomass. The thermo-chemical methods that are employed are gasification, liquefaction and combustion. On gasification biomass yields biogas, on liquefaction biomass yields bio-oil and on combustion biomass yields bio-char. Any attempt to biomass gasification, liquefaction or combustion calls for a good understanding of biomass pyrolysis. So, Irrespective of the method used the first step towards the thermo-chemical treatment of biomass is pyrolysis. Pyrolysis mainly converts the solid mass into liquid with gas and residual char as the byproducts. Liquid is used for the production of heat, power and many other chemicals whereas the gas and char can be used as fuels to generate heat.

Keywords: biomass, fluidisation, pyrolysis, simulation

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22136 Dynamic Soil Structure Interaction in Buildings

Authors: Shreya Thusoo, Karan Modi, Ankit Kumar Jha, Rajesh Kumar

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Since the evolution of computational tools and simulation software, there has been considerable increase in research on Soil Structure Interaction (SSI) to decrease the computational time and increase accuracy in the results. To aid the designer with a proper understanding of the response of structure in different soil types, the presented paper compares the deformation, shear stress, acceleration and other parameters of multi-storey building for a specific input ground motion using Response-spectrum Analysis (RSA) method. The response of all the models of different heights have been compared in different soil types. Finite Element Simulation software, ANSYS, has been used for all the computational purposes. Overall, higher response is observed with SSI, while it increases with decreasing stiffness of soil.

Keywords: soil-structure interaction, response spectrum, analysis, finite element method, multi-storey buildings

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22135 Software Transactional Memory in a Dynamic Programming Language at Virtual Machine Level

Authors: Szu-Kai Hsu, Po-Ching Lin

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As more and more multi-core processors emerge, traditional sequential programming paradigm no longer suffice. Yet only few modern dynamic programming languages can leverage such advantage. Ruby, for example, despite its wide adoption, only includes threads as a simple parallel primitive. The global virtual machine lock of official Ruby runtime makes it impossible to exploit full parallelism. Though various alternative Ruby implementations do eliminate the global virtual machine lock, they only provide developers dated locking mechanism for data synchronization. However, traditional locking mechanism error-prone by nature. Software Transactional Memory is one of the promising alternatives among others. This paper introduces a new virtual machine: GobiesVM to provide a native software transactional memory based solution for dynamic programming languages to exploit parallelism. We also proposed a simplified variation of Transactional Locking II algorithm. The empirical results of our experiments show that support of STM at virtual machine level enables developers to write straightforward code without compromising parallelism or sacrificing thread safety. Existing source code only requires minimal or even none modi cation, which allows developers to easily switch their legacy codebase to a parallel environment. The performance evaluations of GobiesVM also indicate the difference between sequential and parallel execution is significant.

Keywords: global interpreter lock, ruby, software transactional memory, virtual machine

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22134 Estimation of World Steel Production by Process

Authors: Reina Kawase

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World GHG emissions should be reduced 50% by 2050 compared with 1990 level. CO2 emission reduction from steel sector, an energy-intensive sector, is essential. To estimate CO2 emission from steel sector in the world, estimation of steel production is required. The world steel production by process is estimated during the period of 2005-2050. The world is divided into aggregated 35 regions. For a steel making process, two kinds of processes are considered; basic oxygen furnace (BOF) and electric arc furnace (EAF). Steel production by process in each region is decided based on a current production capacity, supply-demand balance of steel and scrap, technology innovation of steel making, steel consumption projection, and goods trade. World steel production under moderate countermeasure scenario in 2050 increases by 1.3 times compared with that in 2012. When domestic scrap recycling is promoted, steel production in developed regions increases about 1.5 times. The share in developed regions changes from 34 %(2012) to about 40%(2050). This is because developed regions are main suppliers of scrap. 48-57% of world steel production is produced by EAF. Under the scenario which thinks much of supply-demand balance of steel, steel production in developing regions increases is 1.4 times and is larger than that in developed regions. The share in developing regions, however, is not so different from current level. The increase in steel production by EAF is the largest under the scenario in which supply-demand balance of steel is an important factor. The share reaches 65%.

Keywords: global steel production, production distribution scenario, steel making process, supply-demand balance

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22133 Determination of Safe Ore Extraction Methodology beneath Permanent Extraction in a Lead Zinc Mine with the Help of FLAC3D Numerical Model

Authors: Ayan Giri, Lukaranjan Phukan, Shantanu Karmakar

Abstract:

Structure and tectonics play a vital role in ore genesis and deposition. The existence of a swelling structure below the current level of a mine leads to the discovery of ores below some permeant developments of the mine. The discovery and the extraction of the ore body are very critical to sustain the business requirement of the mine. The challenge was to extract the ore without hampering the global stability of the mine. In order to do so, different mining options were considered and analysed by numerical modelling in FLAC3d software. The constitutive model prepared for this simulation is the improved unified constitutive model, which can better and more accurately predict the stress-strain relationships in a continuum model. The IUCM employs the Hoek-Brown criterion to determine the instantaneous Mohr-Coulomb parameters cohesion (c) and friction (ɸ) at each level of confining stress. The extra swelled part can be dimensioned as north-south strike width 50m, east-west strike width 50m. On the north side, already a stope (P1) is excavated of the dimension of 25m NS width. The different options considered were (a) Open stoping of extraction of southern part (P0) of 50m to the full extent, (b) Extraction of the southern part of 25m, then filling of both the primaries and extraction of secondary (S0) 25m in between. (c) Extraction of the southern part (P0) completely, preceded by backfill and modify the design of the secondary (S0) for the overall stability of the permanent excavation above the stoping.

Keywords: extraction, IUCM, FLAC 3D, stoping, tectonics

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22132 Simplified Analysis Procedure for Seismic Evaluation of Tall Building at Structure and Component Level

Authors: Tahir Mehmood, Pennung Warnitchai

Abstract:

Simplified static analysis procedures such Nonlinear Static Procedure (NSP) are gaining popularity for the seismic evaluation of buildings. However, these simplified procedures accounts only for the seismic responses of the fundamental vibration mode of the structure. Some other procedures which can take into account the higher modes of vibration, lack in accuracy to determine the component responses. Hence, such procedures are not suitable for evaluating the structures where many vibration modes may participate significantly or where component responses are needed to be evaluated. Moreover, these procedures were found to either computationally expensive or tedious to obtain individual component responses. In this paper, a simplified but accurate procedure is studied. It is called the Uncoupled Modal Response History Analysis (UMRHA) procedure. In this procedure, the nonlinear response of each vibration mode is first computed, and they are later on combined into the total response of the structure. The responses of four tall buildings are computed by this simplified UMRHA procedure and compared with those obtained from the NLRHA procedure. The comparison shows that the UMRHA procedure is able to accurately compute the global responses, i.e., story shears and story overturning moments, floor accelerations and inter-story drifts as well as the component level responses of these tall buildings with heights varying from 20 to 44 stories. The required computational effort is also extremely low compared to that of the Nonlinear Response History Analysis (NLRHA) procedure.

Keywords: higher mode effects, seismic evaluation procedure, tall buildings, component responses

Procedia PDF Downloads 336
22131 The Metacognition Levels of Students: A Research School of Physical Education and Sports at Anadolu University

Authors: Dilek Yalız Solmaz

Abstract:

Meta-cognition is an important factor for educating conscious individuals who are aware of their cognitive processes. With this respect, the purposes of this article is to find out the perceived metacognition level of Physical Education and Sports School students at Anadolu University and to identify whether metacognition levels display significant differences in terms of various variables. 416 Anadolu University Physical Education and Sports School students were formed the research universe. "The Meta-Cognitions Questionnaire (MCQ-30)" developed by Cartwright-Hatton and Wells and later developed the 30-item short form (MCQ-30) was used. The MCQ-30 which was adapted into Turkish by Tosun and Irak is a four-point agreement scale. In the data analysis, arithmethic mean, standard deviation, t-test and ANOVA were used. There is no statistical difference between mean scores of uncontrollableness and danger, cognitive awareness, cognitive confidence and the positive beliefs of girls and boys students. There is a statistical difference between mean scores of the need to control thinking. There is no statistical difference according to departments of students between mean scores of uncontrollableness and danger, cognitive awareness, cognitive confidence, need to control thinking and the positive beliefs. There is no statistical difference according to grade level of students between mean scores of the positive beliefs, cognitive confidence and need to control thinking. There is a statistical difference between mean scores of uncontrollableness and danger and cognitive awareness.

Keywords: meta cognition, physical education, sports school students, thinking

Procedia PDF Downloads 370
22130 Audio-Visual Aids and the Secondary School Teaching

Authors: Shrikrishna Mishra, Badri Yadav

Abstract:

In this complex society of today where experiences are innumerable and varied, it is not at all possible to present every situation in its original colors hence the opportunities for learning by actual experiences always are not at all possible. It is only through the use of proper audio visual aids that the life situation can be trough in the class room by an enlightened teacher in their simplest form and representing the original to the highest point of similarity which is totally absent in the verbal or lecture method. In the presence of audio aids, the attention is attracted interest roused and suitable atmosphere for proper understanding is automatically created, but in the existing traditional method greater efforts are to be made in order to achieve the aforesaid essential requisite. Inspire of the best and sincere efforts on the side of the teacher the net effect as regards understanding or learning in general is quite negligible.

Keywords: Audio-Visual Aids, the secondary school teaching, complex society, audio

Procedia PDF Downloads 471
22129 Understanding Indonesian Smallholder Dairy Farmers’ Decision to Adopt Multiple Farm: Level Innovations

Authors: Rida Akzar, Risti Permani, Wahida , Wendy Umberger

Abstract:

Adoption of farm innovations may increase farm productivity, and therefore improve market access and farm incomes. However, most studies that look at the level and drivers of innovation adoption only focus on a specific type of innovation. Farmers may consider multiple innovation options, and constraints such as budget, environment, scarcity of labour supply, and the cost of learning. There have been some studies proposing different methods to combine a broad variety of innovations into a single measurable index. However, little has been done to compare these methods and assess whether they provide similar information about farmer segmentation by their ‘innovativeness’. Using data from a recent survey of 220 dairy farm households in West Java, Indonesia, this study compares and considers different methods of deriving an innovation index, including expert-weighted innovation index; an index derived from the total number of adopted technologies; and an index of the extent of adoption of innovation taking into account both adoption and disadoption of multiple innovations. Second, it examines the distribution of different farming systems taking into account their innovativeness and farm characteristics. Results from this study will inform policy makers and stakeholders in the dairy industry on how to better design, target and deliver programs to improve and encourage farm innovation, and therefore improve farm productivity and the performance of the dairy industry in Indonesia.

Keywords: adoption, dairy, household survey, innovation index, Indonesia, multiple innovations dairy, West Java

Procedia PDF Downloads 327
22128 Modified Ninhydrin Reagent for the Detection of Amino Acids on TLC Paper

Authors: H. Elgubbi, A. Mlitan, A. Alzridy

Abstract:

Ninhydrin is the most well known spray reagent for identification of amino acids. Spring with Ninhydrin as a non-specific reagent is well-known and widely used for its remarkable high sensitivity. Using Ninhydrin reagent alone to detect amino acid on thin layer chromatography (TLA) paper is not advisable due to its lower sensitivity. A new spray reagent, Stannus chloride solution (Sn CL2) has been used to detect amino acids on filtter paper (witman 14) and TLC paper, silica Gel, 60 F254 TLC Aluminium Sheet 20x20cm Merck- Germany. Also, modified TLC pre-staining method was used, which only consisted of 3 steps: spotting, separating and color. The improved method was rapid and inexpensive and the results obtained were clear and reliable. In addition, it is suitable for screening different amino acid.

Keywords: amino acid, ninhydrin, modified ninhydrin reagent, stannus chloride reagent, thin-layer chromatography (TLC), TLC pre-staining

Procedia PDF Downloads 410
22127 A Discrete Element Method Centrifuge Model of Monopile under Cyclic Lateral Loads

Authors: Nuo Duan, Yi Pik Cheng

Abstract:

This paper presents the data of a series of two-dimensional Discrete Element Method (DEM) simulations of a large-diameter rigid monopile subjected to cyclic loading under a high gravitational force. At present, monopile foundations are widely used to support the tall and heavy wind turbines, which are also subjected to significant from wind and wave actions. A safe design must address issues such as rotations and changes in soil stiffness subject to these loadings conditions. Design guidance on the issue is limited, so are the availability of laboratory and field test data. The interpretation of these results in sand, such as the relation between loading and displacement, relies mainly on empirical correlations to pile properties. Regarding numerical models, most data from Finite Element Method (FEM) can be found. They are not comprehensive, and most of the FEM results are sensitive to input parameters. The micro scale behaviour could change the mechanism of the soil-structure interaction. A DEM model was used in this paper to study the cyclic lateral loads behaviour. A non-dimensional framework is presented and applied to interpret the simulation results. The DEM data compares well with various set of published experimental centrifuge model test data in terms of lateral deflection. The accumulated permanent pile lateral displacements induced by the cyclic lateral loads were found to be dependent on the characteristics of the applied cyclic load, such as the extent of the loading magnitudes and directions.

Keywords: cyclic loading, DEM, numerical modelling, sands

Procedia PDF Downloads 312
22126 Unified Power Quality Conditioner Presentation and Dimensioning

Authors: Abderrahmane Kechich, Othmane Abdelkhalek

Abstract:

Static converters behave as nonlinear loads that inject harmonic currents into the grid and increase the consumption of the inactive power. On the other hand, the increased use of sensitive equipment requires the application of sinusoidal voltages. As a result, the electrical power quality control has become a major concern in the field of power electronics. In this context, the active power conditioner (UPQC) was developed. It combines both serial and parallel structures; the series filter can protect sensitive loads and compensate for voltage disturbances such as voltage harmonics, voltage dips or flicker when the shunt filter compensates for current disturbances such as current harmonics, reactive currents and imbalance. This double feature is that it is one of the most appropriate devices. Calculating parameters is an important step and in the same time it’s not easy for that reason several researchers based on trial and error method for calculating parameters but this method is not easy for beginners researchers especially what about the controller’s parameters, for that reason this paper gives a mathematical way to calculate of almost all of UPQC parameters away from trial and error method. This paper gives also a new approach for calculating of PI regulators parameters for purpose to have a stable UPQC able to compensate for disturbances acting on the waveform of line voltage and load current in order to improve the electrical power quality.

Keywords: UPQC, Shunt active filer, series active filer, PI controller, PWM control, dual-loop control

Procedia PDF Downloads 389
22125 An AK-Chart for the Non-Normal Data

Authors: Chia-Hau Liu, Tai-Yue Wang

Abstract:

Traditional multivariate control charts assume that measurement from manufacturing processes follows a multivariate normal distribution. However, this assumption may not hold or may be difficult to verify because not all the measurement from manufacturing processes are normal distributed in practice. This study develops a new multivariate control chart for monitoring the processes with non-normal data. We propose a mechanism based on integrating the one-class classification method and the adaptive technique. The adaptive technique is used to improve the sensitivity to small shift on one-class classification in statistical process control. In addition, this design provides an easy way to allocate the value of type I error so it is easier to be implemented. Finally, the simulation study and the real data from industry are used to demonstrate the effectiveness of the propose control charts.

Keywords: multivariate control chart, statistical process control, one-class classification method, non-normal data

Procedia PDF Downloads 413