Search results for: maximum entropy modeling
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7908

Search results for: maximum entropy modeling

4878 A Calibration Method for Temperature Distribution Measurement of Thermochromic Liquid Crystal Based on Mathematical Morphology of Hue Image

Authors: Risti Suryantari, Flaviana

Abstract:

The aim of this research is to design calibration method of Thermochromic Liquid Crystal for temperature distribution measurement based on mathematical morphology of hue image A glass of water is placed on the surface of sample TLC R25C5W at certain temperature. We use scanner for image acquisition. The true images in RGB format is converted to HSV (hue, saturation, value) by taking of hue without saturation and value. Then the hue images is processed based on mathematical morphology using Matlab2013a software to get better images. There are differences on the final images after processing at each temperature variation based on visualization observation and the statistic value. The value of maximum and mean increase with rising temperature. It could be parameter to identify the temperature of the human body surface like hand or foot surface.

Keywords: thermochromic liquid crystal, TLC, mathematical morphology, hue image

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4877 Lithium-Ion Battery State of Charge Estimation Using One State Hysteresis Model with Nonlinear Estimation Strategies

Authors: Mohammed Farag, Mina Attari, S. Andrew Gadsden, Saeid R. Habibi

Abstract:

Battery state of charge (SOC) estimation is an important parameter as it measures the total amount of electrical energy stored at a current time. The SOC percentage acts as a fuel gauge if it is compared with a conventional vehicle. Estimating the SOC is, therefore, essential for monitoring the amount of useful life remaining in the battery system. This paper looks at the implementation of three nonlinear estimation strategies for Li-Ion battery SOC estimation. One of the most common behavioral battery models is the one state hysteresis (OSH) model. The extended Kalman filter (EKF), the smooth variable structure filter (SVSF), and the time-varying smoothing boundary layer SVSF are applied on this model, and the results are compared.

Keywords: state of charge estimation, battery modeling, one-state hysteresis, filtering and estimation

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4876 A Quantitative Structure-Adsorption Study on Novel and Emerging Adsorbent Materials

Authors: Marc Sader, Michiel Stock, Bernard De Baets

Abstract:

Considering a large amount of adsorption data of adsorbate gases on adsorbent materials in literature, it is interesting to predict such adsorption data without experimentation. A quantitative structure-activity relationship (QSAR) is developed to correlate molecular characteristics of gases and existing knowledge of materials with their respective adsorption properties. The application of Random Forest, a machine learning method, on a set of adsorption isotherms at a wide range of partial pressures and concentrations is studied. The predicted adsorption isotherms are fitted to several adsorption equations to estimate the adsorption properties. To impute the adsorption properties of desired gases on desired materials, leave-one-out cross-validation is employed. Extensive experimental results for a range of settings are reported.

Keywords: adsorption, predictive modeling, QSAR, random forest

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4875 Brand Management Model in Professional Football League

Authors: Vajiheh Javani

Abstract:

The study aims to examine brand image in Iran's professional Football League (2014-2015). The study was descriptive survey one. A sample of Iranian professional football league fans (N=911) responded four items questionnaire. A structural equation model (SEM) test with maximum likelihood estimation was performed to test the relationships among the research variables. The analyses of data showed three dimensions of brand image influenced on fan’s brand loyalty of which the attitude was the most important. Benefits and attributes were placed in the second and third rank respectively. According to results, brand image plays a pivotal role between Iranian fans brand loyalty. Create an attractive and desirable brand image in the fans mind increases brand loyalty. Moreover due to, revenue and profits increase through ticket sales and products of club and also attract more sponsors.

Keywords: brand management, sport industry, brand image, fans

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4874 Failure Criterion for Mixed Mode Fracture of Cracked Wood Specimens

Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi

Abstract:

Investigation of fracture of wood components can prevent from catastrophic failures. Created fracture process zone (FPZ) in crack tip vicinity has important effect on failure of cracked composite materials. In this paper, a failure criterion for fracture investigation of cracked wood specimens under mixed mode I/II loading is presented. This criterion is based on maximum strain energy release rate and material nonlinearity in the vicinity of crack tip due to presence of microcracks. Verification of results with available experimental data proves the coincidence of the proposed criterion with the nature of fracture of wood. To simplify the estimation of nonlinear properties of FPZ, a damage factor is also introduced for engineering and application purposes.

Keywords: fracture criterion, mixed mode loading, damage zone, micro cracks

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4873 An Approach to Analyze Testing of Nano On-Chip Networks

Authors: Farnaz Fotovvatikhah, Javad Akbari

Abstract:

Test time of a test architecture is an important factor which depends on the architecture's delay and test patterns. Here a new architecture to store the test results based on network on chip is presented. In addition, simple analytical model is proposed to calculate link test time for built in self-tester (BIST) and external tester (Ext) in multiprocessor systems. The results extracted from the model are verified using FPGA implementation and experimental measurements. Systems consisting 16, 25, and 36 processors are implemented and simulated and test time is calculated. In addition, BIST and Ext are compared in terms of test time at different conditions such as at different number of test patterns and nodes. Using the model the maximum frequency of testing could be calculated and the test structure could be optimized for high speed testing.

Keywords: test, nano on-chip network, JTAG, modelling

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4872 Strongly Disordered Conductors and Insulators in Holography

Authors: Matthew Stephenson

Abstract:

We study the electrical conductivity of strongly disordered, strongly coupled quantum field theories, holographically dual to non-perturbatively disordered uncharged black holes. The computation reduces to solving a diffusive hydrostatic equation for an emergent horizon fluid. We demonstrate that a large class of theories in two spatial dimensions have a universal conductivity independent of disorder strength, and rigorously rule out disorder-driven conductor-insulator transitions in many theories. We present a (fine-tuned) axion-dilaton bulk theory which realizes the conductor-insulator transition, interpreted as a classical percolation transition in the horizon fluid. We address aspects of strongly disordered holography that can and cannot be addressed via mean-field modeling, such as massive gravity.

Keywords: theoretical physics, black holes, holography, high energy

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4871 Tracing the Developmental Repertoire of the Progressive: Evidence from L2 Construction Learning

Authors: Tianqi Wu, Min Wang

Abstract:

Research investigating language acquisition from a constructionist perspective has demonstrated that language is learned as constructions at various linguistic levels, which is related to factors of frequency, semantic prototypicality, and form-meaning contingency. However, previous research on construction learning tended to focus on clause-level constructions such as verb argument constructions but few attempts were made to study morpheme-level constructions such as the progressive construction, which is regarded as a source of acquisition problems for English learners from diverse L1 backgrounds, especially for those whose L1 do not have an equivalent construction such as German and Chinese. To trace the developmental trajectory of Chinese EFL learners’ use of the progressive with respect to verb frequency, verb-progressive contingency, and verbal prototypicality and generality, a learner corpus consisting of three sub-corpora representing three different English proficiency levels was extracted from the Chinese Learners of English Corpora (CLEC). As the reference point, a native speakers’ corpus extracted from the Louvain Corpus of Native English Essays was also established. All the texts were annotated with C7 tagset by part-of-speech tagging software. After annotation all valid progressive hits were retrieved with AntConc 3.4.3 followed by a manual check. Frequency-related data showed that from the lowest to the highest proficiency level, (1) the type token ratio increased steadily from 23.5% to 35.6%, getting closer to 36.4% in the native speakers’ corpus, indicating a wider use of verbs in the progressive; (2) the normalized entropy value rose from 0.776 to 0.876, working towards the target score of 0.886 in native speakers’ corpus, revealing that upper-intermediate learners exhibited a more even distribution and more productive use of verbs in the progressive; (3) activity verbs (i.e., verbs with prototypical progressive meanings like running and singing) dropped from 59% to 34% but non-prototypical verbs such as state verbs (e.g., being and living) and achievement verbs (e.g., dying and finishing) were increasingly used in the progressive. Apart from raw frequency analyses, collostructional analyses were conducted to quantify verb-progressive contingency and to determine what verbs were distinctively associated with the progressive construction. Results were in line with raw frequency findings, which showed that contingency between the progressive and non-prototypical verbs represented by light verbs (e.g., going, doing, making, and coming) increased as English proficiency proceeded. These findings altogether suggested that beginning Chinese EFL learners were less productive in using the progressive construction: they were constrained by a small set of verbs which had concrete and typical progressive meanings (e.g., the activity verbs). But with English proficiency increasing, their use of the progressive began to spread to marginal members such as the light verbs.

Keywords: Construction learning, Corpus-based, Progressives, Prototype

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4870 The Impact of the Number of Neurons in the Hidden Layer on the Performance of MLP Neural Network: Application to the Fast Identification of Toxics Gases

Authors: Slimane Ouhmad, Abdellah Halimi

Abstract:

In this work, we have applied neural networks method MLP type to a database from an array of six sensors for the detection of three toxic gases. As the choice of the number of hidden layers and the weight values has a great influence on the convergence of the learning algorithm, we proposed, in this article, a mathematical formulation to determine the optimal number of hidden layers and good weight values based on the method of back propagation of errors. The results of this modeling have improved discrimination of these gases on the one hand, and optimize the computation time on the other hand, the comparison to other results achieved in this case.

Keywords: MLP Neural Network, back-propagation, number of neurons in the hidden layer, identification, computing time

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4869 Asymptotic Expansion of the Korteweg-de Vries-Burgers Equation

Authors: Jian-Jun Shu

Abstract:

It is common knowledge that many physical problems (such as non-linear shallow-water waves and wave motion in plasmas) can be described by the Korteweg-de Vries (KdV) equation, which possesses certain special solutions, known as solitary waves or solitons. As a marriage of the KdV equation and the classical Burgers (KdVB) equation, the Korteweg-de Vries-Burgers (KdVB) equation is a mathematical model of waves on shallow water surfaces in the presence of viscous dissipation. Asymptotic analysis is a method of describing limiting behavior and is a key tool for exploring the differential equations which arise in the mathematical modeling of real-world phenomena. By using variable transformations, the asymptotic expansion of the KdVB equation is presented in this paper. The asymptotic expansion may provide a good gauge on the validation of the corresponding numerical scheme.

Keywords: asymptotic expansion, differential equation, Korteweg-de Vries-Burgers (KdVB) equation, soliton

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4868 Penetration Analysis for Composites Applicable to Military Vehicle Armors, Aircraft Engines and Nuclear Power Plant Structures

Authors: Dong Wook Lee

Abstract:

This paper describes a method for analyzing penetration for composite material using an explicit nonlinear Finite Element Analysis (FEA). This method may be used in the early stage of design for the protection of military vehicles, aircraft engines and nuclear power plant structures made of composite materials. This paper deals with simple ballistic penetration tests for composite materials and the FEA modeling method and results. The FEA was performed to interpret the ballistic field test phenomenon regarding the damage propagation in the structure subjected to local foreign object impact.

Keywords: computer aided engineering, finite element analysis, impact analysis, penetration analysis, composite material

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4867 Trace Metals in Natural Bottled Water on Montenegrin Market and Comaparison with Tap Water in Podgorica

Authors: Katarina Živković, Ivana Joksimović

Abstract:

Many different chemicals may occur in drinking water and cause significant human health risks after prolonged periods of exposure. In particular concern are contaminants that have cumulative toxic properties, such as heavy metals. This investigation was done to clarify concerns about chemical quality and safety of drinking tap water in Podgorica. For comparison, all available natural bottled water on Montenegrin market were bought. All samples (bottled water and tap water from Podgorica) were analyzed using ICP –OES on contents of Al, Cd, Pb, Cu, Zn,Cr, Fe, As and Mn. All results compared with the maximum concentration levels allowed by international standards and World Health Organization (WHO) guidelines. The results of analysis showed that all trace of heavy metals were very low and in same time below MCL according to WHO and International standard.

Keywords: inductively coupled plasma - optical emission spectrometry (ICP-OES), Montenegro (Podgorica), natural bottled water, tap water , trace of heavy metal

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4866 Synthesis and Electromagnetic Property of Li₀.₃₅Zn₀.₃Fe₂.₃₅O₄ Grafted with Polyaniline Fibers

Authors: Jintang Zhou, Zhengjun Yao, Tiantian Yao

Abstract:

Li₀.₃₅Zn₀.₃Fe₂.₃₅O₄(LZFO) grafted with polyaniline (PANI) fibers was synthesized by in situ polymerization. FTIR, XRD, SEM, and vector network analyzer were used to investigate chemical composition, micro-morphology, electromagnetic properties and microwave absorbing properties of the composite. The results show that PANI fibers were grafted on the surfaces of LZFO particles. The reflection loss exceeds 10 dB in the frequency range from 2.5 to 5 GHz and from 15 to 17GHz, and the maximum reflection loss reaches -33 dB at 15.9GHz. The enhanced microwave absorption properties of LZFO/PANI-fiber composites are mainly ascribed to the combined effect of both dielectric loss and magnetic loss and the improved impedance matching.

Keywords: Li₀.₃₅Zn₀.₃Fe₂.₃₅O₄, polyaniline, electromagnetic properties, microwave absorbing properties

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4865 Supercritical CO2 Extraction of Cymbopogon martini Essential Oil and Comparison of Its Composition with Traditionally Extracted Oils

Authors: Aarti Singh, Anees Ahmad

Abstract:

Essential oil was extracted from lemon grass (Cymbopogon martini) with supercritical carbondioxide (SC-CO2) at pressure of 140 bar and temperature of 55 °C and CO2 flow rate of 8 gmin-1, and its composition and yield were compared with other conventional extraction methods of oil, HD (Hydrodistillation), SE (Solvent Extraction), UAE (Ultrasound Assisted Extraction). SC-CO2 extraction is a green and sustainable extraction technique. Each oil was analysed by GC-MS, the major constituents were neral (44%), Z-citral (43%), geranial (27%), caryophyllene (4.6%) and linalool (1%). The essential oil of lemon grass is valued for its neral and citral concentration. The oil obtained by supercritical carbon-dioxide extraction contained maximum concentration of neral (55.05%) whereas ultrasonication extracted oil contained minimum content (5.24%) and it was absent in solvent extracted oil. The antioxidant properties have been assessed by DPPH and superoxide scavenging methods.

Keywords: cymbopogon martini, essential oil, FT-IR, GC-MS, HPTLC, SC-CO2

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4864 Assessment of Breast, Lung and Liver Effective Doses in Heart Imaging by CT-Scan 128 Dual Sources with Use of TLD-100 in RANDO Phantom

Authors: Seyedeh Sepideh Amini, Navideh Aghaei Amirkhizi, Seyedeh Paniz Amini, Seyed Soheil Sayyahi, Mohammad Reza Davar Panah

Abstract:

CT-Scan is one of the lateral and sectional imaging methods that produce 3D-images with use of rotational x-ray tube around central axis. This study is about evaluation and calculation of effective doses around heart organs such as breast, lung and liver with CT-Scan 128 dual sources with TLD_100 and RANDO Phantom by spiral, flash and conventional protocols. In results, it is showed that in spiral protocol organs have maximum effective dose and minimum in flash protocol. Thus flash protocol advised for children and risk persons.

Keywords: X-ray computed tomography, dosimetry, TLD-100, RANDO, phantom

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4863 A DFT-Based QSARs Study of Kovats Retention Indices of Adamantane Derivatives

Authors: Z. Bayat

Abstract:

A quantitative structure–property relationship (QSPR) study was performed to develop models those relate the structures of 65 Kovats retention index (RI) of adamantane derivatives. Molecular descriptors derived solely from 3D structures of the molecular compounds. The usefulness of the quantum chemical descriptors, calculated at the level of the DFT theories using 6-311+G** basis set for QSAR study of adamantane derivatives was examined. The use of descriptors calculated only from molecular structure eliminates the need to experimental determination of properties for use in the correlation and allows for the estimation of RI for molecules not yet synthesized. The prediction results are in good agreement with the experimental value. A multi-parametric equation containing maximum Four descriptors at B3LYP/6-31+G** method with good statistical qualities (R2train=0.913, Ftrain=97.67, R2test=0.770, Ftest=3.21, Q2LOO=0.895, R2adj=0.904, Q2LGO=0.844) was obtained by Multiple Linear Regression using stepwise method.

Keywords: DFT, adamantane, QSAR, Kovat

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4862 Prevalence of the Musculoskeletal Disorder amongst School Teachers

Authors: Nirav Vaghela, Sanket Parekh

Abstract:

Objective: Musculoskeletal disorders (MSD) represent one of the most common and important occupational health problems in working populations, being responsible for a substantial impact on quality of life and incurring a major economic burden in compensation cost and lost wages. School teachers represent an occupational group among which there appears to be a high prevalence of MSD. Design: Three hundred and fourteen teachers were enrolled in this study. Teachers were interview with the Modified Nordic Questionnaire. Result: In current study total 314 participants have been recruited in that minimum age of participants is 22 and maximum age is 59 with mean 40.5± 9.88. Total prevalence of the MSD is 71.95% among the teachers. In that Female were more affected with 72% than the males with 28%. Conclusion: The teachers here in reported a high prevalence of musculoskeletal pain in the shoulder, knee and back.

Keywords: repetitive stress injury, pain, occupational hazards, disability, abneetism, physical health, quality of life

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4861 Analytical Solutions for Corotational Maxwell Model Fluid Arising in Wire Coating inside a Canonical Die

Authors: Muhammad Sohail Khan, Rehan Ali Shah

Abstract:

The present paper applies the optimal homotopy perturbation method (OHPM) and the optimal homotopy asymptotic method (OHAM) introduced recently to obtain analytic approximations of the non-linear equations modeling the flow of polymer in case of wire coating of a corotational Maxwell fluid. Expression for the velocity field is obtained in non-dimensional form. Comparison of the results obtained by the two methods at different values of non-dimensional parameter l10, reveal that the OHPM is more effective and easy to use. The OHPM solution can be improved even working in the same order of approximation depends on the choices of the auxiliary functions.

Keywords: corotational Maxwell model, optimal homotopy asymptotic method, optimal homotopy perturbation method, wire coating die

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4860 Enhancing the Safety Climate and Reducing Violence against Staff in Closed Hospital Wards

Authors: Valerie Isaak

Abstract:

This study examines the effectiveness of an intervention program aimed at enhancing a unit-level safety climate as a way to minimize the risk of employees being injured by patient violence. The intervention program conducted in maximum security units in one of the psychiatric hospitals in Israel included a three day workshop. Safety climate was examined before and after the implementation of the intervention. We also collected data regarding incidents involving patient violence. Six months after the intervention a significant improvement in employees’ perceptions regarding management’s commitment to safety were found as well as a marginally significant improvement in communication concerning safety issues. Our research shows that an intervention program aimed at enhancing a safety climate is associated with a decrease in the number of aggressive incidents. We conclude that such an intervention program is likely to return the sense of safety and reduce the scope of violence.

Keywords: violence, intervention, safety climate, performance, public sector

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4859 Synthesis of Ethoxylated Amide as Bactericide to Enhance the Storage Period of Diesel Fuel Nanoemulsions

Authors: S. M. Abd-Altwab, M. R. Noor El-Din

Abstract:

This paper aims to the synthesis of new ethoxylated amide as bactericides to prevent the growth of Gram +ve and –ve bacteria of water-in-diesel fuel nanoemulsions over a long period of time as three months. To realize it, eight kinetically stable water-in-diesel fuel nanoemulsions differing in surfactant concentrations and water contents ranging from 4 to 8 and 5 to 8 wt.,wt.,% of total weight of the nanoemulsions, respectively were formed at a temperature of 20 °C. The performance of this ethoxylated amide as bactericides agents against two strains of Gram-negative bacteria, namely, Pseudomonas aeruginosa and Escherichia coli, and two strains of Gram-positive bacteria namely, Staphylococcus aureus and Bacillus subtilis, were evaluated as antimicrobial agents. The maximum and minimum antimicrobial activities were 85 and 71 % against S. aureus and E. coli, respectively, at a concentration of 5 mg/l, pH 7, and 37 °C.

Keywords: nanoemulsion, bacteriocide, diesel fuel, emulsifier

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4858 Externalizing Behavior Problems Influencing Social Behavior in Early Adolescence

Authors: Zhidong Zhang, Zhi-Chao Zhang

Abstract:

This study focuses on early adolescent externalizing behavioral problems which specifically concentrate on rule breaking behavior and aggressive behavior using the instrument of Achenbach System of Empirically Based Assessment (ASEBA). The purpose was to analyze the relationships between the externalizing behavioral problems and relevant background variables such as sports activities, hobbies, chores and the number of close friends. The stratified sampling method was used to collect data from 1975 participants. The results indicated that several background variables as predictors could significantly predict rule breaking behavior and aggressive behavior. Further, a hierarchical modeling method was used to explore the causal relations among background variables, breaking behavior variables and aggressive behavior variables.

Keywords: aggressive behavior, breaking behavior, early adolescence, externalizing problem

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4857 Cognitive Based Approach to Organizational Development

Authors: Tatiana V. Korsakova

Abstract:

The cognitive methodology in management is considered: Cognitive structuring - the formation of ideas about the functioning of a developing organization; Cognitive modeling - heuristic construction of existing actions (zone of successful actions); and Cognitive construct - the formation of filters for converting external information into specific events of managerial reality. The major findings of the study are the identification of areas of successful actions in the organization, harmonization of criteria for evaluating the effectiveness of company management, and the frame-description that indicates the connection of environmental elements with the elements of the organization. It is stated the development of specific events of managerial reality in the direction of the further development of the organization depends on the personal cognitive construct of the development-subjects when it is used in the zone of successful actions.

Keywords: cognitive construct, focus of applicability, knowledge corporate culture, zones of successful actions

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4856 Investigating the English Speech Processing System of EFL Japanese Older Children

Authors: Hiromi Kawai

Abstract:

This study investigates the nature of EFL older children’s L2 perceptive and productive abilities using classroom data, in order to find a pedagogical solution to the teaching of L2 sounds at an early stage of learning in a formal school setting. It is still inconclusive whether older children with only EFL formal school instruction at the initial stage of L2 learning are able to attain native-like perception and production in English within the very limited amount of exposure to the target language available. Based on the notion of the lack of study of EFL Japanese children’s acquisition of English segments, the researcher uses a model of L1 speech processing which was developed for investigating L1 English children’s speech and literacy difficulties using a psycholinguistic framework. The model is composed of input channel, output channel, and lexical representation, and examines how a child receives information from spoken or written language, remembers and stores it within the lexical representations and how the child selects and produces spoken or written words. Concerning language universality and language specificity in the language acquisitional process, the aim of finding any sound errors in L1 English children seemed to conform to the author’s intention to find abilities of English sounds in older Japanese children at the novice level of English in an EFL setting. 104 students in Grade 5 (between the ages of 10 and 11 years old) of an elementary school in Tokyo participated in this study. Four tests to measure their perceptive ability and three oral repetition tests to measure their productive ability were conducted with/without reference to lexical representation. All the test items were analyzed to calculate item facility (IF) indices, and correlational analyses and Structural Equation Modeling (SEM) were conducted to examine the relationship between the receptive ability and the productive ability. IF analysis showed that (1) the participants were better at perceiving a segment than producing a segment, (2) they had difficulty in auditory discrimination of paired consonants when one of them does not exist in the Japanese inventory, (3) they had difficulty in both perceiving and producing English vowels, and (4) their L1 loan word knowledge had an influence on their ability to perceive and produce L2 sounds. The result of the Multiple Regression Modeling showed that the two production tests could predict the participants’ auditory ability of real words in English. The result of SEM showed that the hypothesis that perceptive ability affects productive ability was supported. Based on these findings, the author discusses the possible explicit method of teaching English segments to EFL older children in a formal school setting.

Keywords: EFL older children, english segments, perception, production, speech processing system

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4855 PIN-Diode Based Slotted Reconfigurable Multiband Antenna Array for Vehicular Communication

Authors: Gaurav Upadhyay, Nand Kishore, Prashant Ranjan, Shivesh Tripathi, V. S. Tripathi

Abstract:

In this paper, a patch antenna array design is proposed for vehicular communication. The antenna consists of 2-element patch array. The antenna array is operating at multiple frequency bands. The multiband operation is achieved by use of slots at proper locations at the patch. The array is made reconfigurable by use of two PIN-diodes. The antenna is simulated and measured in four states of diodes i.e. ON-ON, ON-OFF, OFF-ON, and OFF-OFF. In ON-ON state of diodes, the resonant frequencies are 4.62-4.96, 6.50-6.75, 6.90-7.01, 7.34-8.22, 8.89-9.09 GHz. In ON-OFF state of diodes, the measured resonant frequencies are 4.63-4.93, 6.50-6.70 and 7.81-7.91 GHz. In OFF-ON states of diodes the resonant frequencies are 1.24-1.46, 3.40-3.75, 5.07-5.25 and 6.90-7.20 GHz and in the OFF-OFF state of diodes 4.49-4.75 and 5.61-5.98 GHz. The maximum bandwidth of the proposed antenna is 16.29%. The peak gain of the antenna is 3.4 dB at 5.9 GHz, which makes it suitable for vehicular communication.

Keywords: antenna, array, reconfigurable, vehicular

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4854 Dilation Effect on 3D Passive Earth Pressure Coefficients for Retaining Wall

Authors: Khelifa Tarek, Benmebarek Sadok

Abstract:

The 2D passive earth pressures acting on rigid retaining walls problem has been widely treated in the literature using different approaches (limit equilibrium, limit analysis, slip line and numerical computation), however, the 3D passive earth pressures problem has received less attention. This paper is concerned with the numerical study of 3D passive earth pressures induced by the translation of a rigid rough retaining wall for associated and non-associated soils. Using the explicit finite difference code FLAC3D, the increase of the passive earth pressures due to the decrease of the wall breadth is investigated. The results given by the present numerical analysis are compared with other investigation. The influence of the angle of dilation on the coefficients is also studied.

Keywords: numerical modeling, FLAC3D, retaining wall, passive earth pressures, angle of dilation

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4853 Approach on Conceptual Design and Dimensional Synthesis of the Linear Delta Robot for Additive Manufacturing

Authors: Efrain Rodriguez, Cristhian Riano, Alberto Alvares

Abstract:

In recent years, robots manipulators with parallel architectures are used in additive manufacturing processes – 3D printing. These robots have advantages such as speed and lightness that make them suitable to help with the efficiency and productivity of these processes. Consequently, the interest for the development of parallel robots for additive manufacturing applications has increased. This article deals with the conceptual design and dimensional synthesis of the linear delta robot for additive manufacturing. Firstly, a methodology based on structured processes for the development of products through the phases of informational design, conceptual design and detailed design is adopted: a) In the informational design phase the Mudge diagram and the QFD matrix are used to aid a set of technical requirements, to define the form, functions and features of the robot. b) In the conceptual design phase, the functional modeling of the system through of an IDEF0 diagram is performed, and the solution principles for the requirements are formulated using a morphological matrix. This phase includes the description of the mechanical, electro-electronic and computational subsystems that constitute the general architecture of the robot. c) In the detailed design phase, a digital model of the robot is drawn on CAD software. A list of commercial and manufactured parts is detailed. Tolerances and adjustments are defined for some parts of the robot structure. The necessary manufacturing processes and tools are also listed, including: milling, turning and 3D printing. Secondly, a dimensional synthesis method applied on design of the linear delta robot is presented. One of the most important key factors in the design of a parallel robot is the useful workspace, which strongly depends on the joint space, the dimensions of the mechanism bodies and the possible interferences between these bodies. The objective function is based on the verification of the kinematic model for a prescribed cylindrical workspace, considering geometric constraints that possibly lead to singularities of the mechanism. The aim is to determine the minimum dimensional parameters of the mechanism bodies for the proposed workspace. A method based on genetic algorithms was used to solve this problem. The method uses a cloud of points with the cylindrical shape of the workspace and checks the kinematic model for each of the points within the cloud. The evolution of the population (point cloud) provides the optimal parameters for the design of the delta robot. The development process of the linear delta robot with optimal dimensions for additive manufacture is presented. The dimensional synthesis enabled to design the mechanism of the delta robot in function of the prescribed workspace. Finally, the implementation of the robotic platform developed based on a linear delta robot in an additive manufacturing application using the Fused Deposition Modeling (FDM) technique is presented.

Keywords: additive manufacturing, delta parallel robot, dimensional synthesis, genetic algorithms

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4852 A Research Review on the Presence of Pesticide Residues in Apples Carried out in Poland in the Years 1980-2015

Authors: Bartosz Piechowicz, Stanislaw Sadlo, Przemyslaw Grodzicki, Magdalena Podbielska

Abstract:

Apples are popular fruits. They are eaten freshly and/or after processing. For instance Golden Delicious is an apple variety commonly used in production of foods for babies and toddlers. It is no wonder that complex analyses of the pesticide residue levels in those fruits have been carried out since eighties, and continued for the next years up to now. The results obtained were presented, usually as a teamwork, at the scientific sessions organised by the (IOR) Institute of Plant Protection-National Research Institute in Poznań and published in Scientific Works of the Institute (now Progress in Plant Protection/ Postępy w Ochronie Roślin) or Journal of Plant Protection Research, and in many non-periodical publications. These reports included studies carried out by IOR Laboratories in Poznań, Sośnicowice, Rzeszów and Bialystok. First detailed studies on the presence of pesticide residues in apple fruits by the laboratory in Rzeszów were published in 1991 in the article entitled 'The presence of pesticides in apples of late varieties from the area of south-eastern Poland in the years 1986-1989', in Annals of National Institute of Hygiene in Warsaw. These surveys gave the scientific base for business contacts between the Polish company Alima and the American company Gerber. At the beginning of XXI century, in Poland, systematic and complex studies on the deposition of pesticide residues in apples were initiated. First of all, the levels of active ingredients of plant protection products applied against storage diseases at 2-3 weeks before the harvest were determined. It is known that the above mentioned substances usually generate the highest residue levels. Also, the assessment of the fungicide residues in apples during their storage in controlled atmosphere and during their processing was carried out. Taking into account the need of actualisation the Maximum Residue Levels of pesticides, in force in Poland and in other European countries, and rationalisation of the ways of their determination, a lot of field tests on the behaviour of more important fungicides on the mature fruits just before their harvesting, were carried out. A rate of their disappearance and mathematical equation that showed the relationship between the residue level of any substance and the used dose, have been determined. The two parameters have allowed to evaluate the Maximum Residue Levels (MRLs) of pesticides, which were in force at that time, and to propose a coherent model of their determination in respect to the new substances. The obtained results were assessed in terms of the health risk for adult consumers and children, and to such determination of terms of treatment that mature apples could meet the rigorous level of 0.01 mg/kg.

Keywords: apple, disappearance, health risk, MRL, pesticide residue, research

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4851 Estimation of Pressure Loss Coefficients in Combining Flows Using Artificial Neural Networks

Authors: Shahzad Yousaf, Imran Shafi

Abstract:

This paper presents a new method for calculation of pressure loss coefficients by use of the artificial neural network (ANN) in tee junctions. Geometry and flow parameters are feed into ANN as the inputs for purpose of training the network. Efficacy of the network is demonstrated by comparison of the experimental and ANN based calculated data of pressure loss coefficients for combining flows in a tee junction. Reynolds numbers ranging from 200 to 14000 and discharge ratios varying from minimum to maximum flow for calculation of pressure loss coefficients have been used. Pressure loss coefficients calculated using ANN are compared to the models from literature used in junction flows. The results achieved after the application of ANN agrees reasonably to the experimental values.

Keywords: artificial neural networks, combining flow, pressure loss coefficients, solar collector tee junctions

Procedia PDF Downloads 373
4850 Modeling and Analysis Of Occupant Behavior On Heating And Air Conditioning Systems In A Higher Education And Vocational Training Building In A Mediterranean Climate

Authors: Abderrahmane Soufi

Abstract:

The building sector is the largest consumer of energy in France, accounting for 44% of French consumption. To reduce energy consumption and improve energy efficiency, France implemented an energy transition law targeting 40% energy savings by 2030 in the tertiary building sector. Building simulation tools are used to predict the energy performance of buildings but the reliability of these tools is hampered by discrepancies between the real and simulated energy performance of a building. This performance gap lies in the simplified assumptions of certain factors, such as the behavior of occupants on air conditioning and heating, which is considered deterministic when setting a fixed operating schedule and a fixed interior comfort temperature. However, the behavior of occupants on air conditioning and heating is stochastic, diverse, and complex because it can be affected by many factors. Probabilistic models are an alternative to deterministic models. These models are usually derived from statistical data and express occupant behavior by assuming a probabilistic relationship to one or more variables. In the literature, logistic regression has been used to model the behavior of occupants with regard to heating and air conditioning systems by considering univariate logistic models in residential buildings; however, few studies have developed multivariate models for higher education and vocational training buildings in a Mediterranean climate. Therefore, in this study, occupant behavior on heating and air conditioning systems was modeled using logistic regression. Occupant behavior related to the turn-on heating and air conditioning systems was studied through experimental measurements collected over a period of one year (June 2023–June 2024) in three classrooms occupied by several groups of students in engineering schools and professional training. Instrumentation was provided to collect indoor temperature and indoor relative humidity in 10-min intervals. Furthermore, the state of the heating/air conditioning system (off or on) and the set point were determined. The outdoor air temperature, relative humidity, and wind speed were collected as weather data. The number of occupants, age, and sex were also considered. Logistic regression was used for modeling an occupant turning on the heating and air conditioning systems. The results yielded a proposed model that can be used in building simulation tools to predict the energy performance of teaching buildings. Based on the first months (summer and early autumn) of the investigations, the results illustrate that the occupant behavior of the air conditioning systems is affected by the indoor relative humidity and temperature in June, July, and August and by the indoor relative humidity, temperature, and number of occupants in September and October. Occupant behavior was analyzed monthly, and univariate and multivariate models were developed.

Keywords: occupant behavior, logistic regression, behavior model, mediterranean climate, air conditioning, heating

Procedia PDF Downloads 49
4849 Friction Stir Welding of Al-Mg-Mn Aluminum Alloy Plates: A Review

Authors: K. Subbaiah, C. V. Jayakumar

Abstract:

Friction stir welding is a solid state welding process. Friction stir welding process eliminates the defects found in fusion welding processes. It is environmentally friend process. 5000 and 6000 series aluminum alloys are widely used in the transportation industries. The Al-Mg-Mn (5000) and Al-Mg-Si (6000) alloys are preferably offer best combination of use in Marine construction. The medium strength and high corrosion resistant 5000 series alloys are the aluminum alloys, which are found maximum utility in the world. In this review, the tool pin profile, process parameters such as hardness, yield strength and tensile strength, and microstructural evolution of friction stir welding of Al-Mg-Mn alloys (5000 Series) have been discussed.

Keywords: Al-Mg-Mn alloys, friction stir welding, tool pin profile, microstructure and mechanical properties

Procedia PDF Downloads 422