Search results for: higher order kinematic specifications
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 22975

Search results for: higher order kinematic specifications

22615 Application and Assessment of Artificial Neural Networks for Biodiesel Iodine Value Prediction

Authors: Raquel M. De sousa, Sofiane Labidi, Allan Kardec D. Barros, Alex O. Barradas Filho, Aldalea L. B. Marques

Abstract:

Several parameters are established in order to measure biodiesel quality. One of them is the iodine value, which is an important parameter that measures the total unsaturation within a mixture of fatty acids. Limitation of unsaturated fatty acids is necessary since warming of a higher quantity of these ones ends in either formation of deposits inside the motor or damage of lubricant. Determination of iodine value by official procedure tends to be very laborious, with high costs and toxicity of the reagents, this study uses an artificial neural network (ANN) in order to predict the iodine value property as an alternative to these problems. The methodology of development of networks used 13 esters of fatty acids in the input with convergence algorithms of backpropagation type were optimized in order to get an architecture of prediction of iodine value. This study allowed us to demonstrate the neural networks’ ability to learn the correlation between biodiesel quality properties, in this case iodine value, and the molecular structures that make it up. The model developed in the study reached a correlation coefficient (R) of 0.99 for both network validation and network simulation, with Levenberg-Maquardt algorithm.

Keywords: artificial neural networks, biodiesel, iodine value, prediction

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22614 Grain Growth Behavior of High Carbon Microalloyed Steels Containing Very Low Amounts of Niobium

Authors: Huseyin Zengin, Muhammet Emre Turan, Yunus Turen, Hayrettin Ahlatci, Yavuz Sun

Abstract:

This study aimed for understanding the effects of dilute Nb additions on the austenite microstructure of microalloyed steels at five different reheating temperatures from 950 °C to 1300 °C. Four microalloyed high-carbon steels having 0.8 %wt C were examined in which three of them had varying Nb concentrations from 0.005 wt% to 0.02 wt% and one of them had no Nb concentration. The quantitative metallographic techniques were used to measure the average prior austenite grain size in order to compare the grain growth pinning effects of Nb precipitates as a function of reheating temperature. Due to the higher stability of the precipitates with increasing Nb concentrations, the grain coarsening temperature that resulted in inefficient grain growth impediment and a bimodal grain distribution in the microstructure, showed an increase with increasing Nb concentration. The respective grain coarsening temperatures (T_GC) in an ascending order for the steels having 0.005 wt% Nb, 0.01 wt% Nb and 0.02 wt% Nb were 950 °C, 1050 °C and 1150 °C. According to these observed grain coarsening temperatures, an approximation was made considering the complete dissolution temperature (T_DISS) of second phase particles as T_GC=T_DISS-300. On the other hand, the plain carbon steel did not show abnormal grain growth behaviour due to the absence of second phase particles. It was also observed that the higher the Nb concentration, the smaller the average prior austenite grain size although the small increments in Nb concenration did not change the average grain size considerably.

Keywords: microalloyed steels, prior austenite grains, second phase particles, grain coarsening temperature

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22613 Teachers’ Education in Brazil: A Case Study on Students’ Performance

Authors: Priscila A. M. Rodrigues

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In Brazil, higher education is usually offered in three parts of the day: in the morning, afternoon and evening. Students have to decide what part of the day they are going to study in the application process. Most of the admitted students who choose to study in the evening also work during the day, because of their financial conditions. Brazilian higher education courses in the evening were initially created to meet the demand for teacher training. These teacher-training courses are socially discredited and considered easily accessible in the country, mostly due to the fact that students who enroll for those courses come from very poor basic education. The research has analyzed the differences between the social profiles and studying conditions of students of teacher education, especially the training intended for would-be elementary education teachers. An investigation has been conducted with these undergraduate students, who were divided into a group of those who study both in the morning and in the afternoon (group 1) and a group of those who study in the evening (group 2). The hypothesis predicted that students in group 1 would perform better than students in group 2. The analysis of training and studying conditions departed from the point of view of students and their teachers. The hypothesis predicted that students in group 1 would perform better than students in group 2. The analysis of training and studying conditions departed from the point of view of students and their teachers. Data was collected from survey, qualitative interviews, field observation and reports from students. Sociological concepts of habitus, cultural capital, trajectories and strategies are essential for this study as well as the literature on quality of higher education. The research revealed that there are differences of studying conditions between group 1 and group 2, precisely when it comes to the university atmosphere, that is to say, academic support resources and enrichment activities which promote educational, cultural and social opportunities, for example conferences, events, scholarships of different types, etc. In order to counteract the effects of their poor educational performance, students who generally come from popular strata require conditions of greater dedication and investment in higher education, which most of them do not have. Despite the considerable difficulties that students in group 2 encounter in their academic experience, the university experience per se brings a gain for the lives of these students, which translates into the expansion of their capital structure – i.e. symbolic, cultural and educational capital – with repercussions on their social trajectory, especially in professional conditions.

Keywords: higher education, higher education students’ performance, quality of higher education, teacher’s education

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22612 Fractional Order Sallen-Key Filters

Authors: Ahmed Soltan, Ahmed G. Radwan, Ahmed M. Soliman

Abstract:

This work aims to generalize the integer order Sallen-Key filters into the fractional-order domain. The analysis in the case of two different fractional-order elements introduced where the general transfer function becomes four terms which are unusual in the conventional case. In addition, the effect of the transfer function parameters on the filter poles and hence the stability is introduced and closed forms for the filter critical frequencies are driven. Finally, different examples of the fractional order Sallen-Key filter design are presented with circuit simulations using ADS where a great matching between the numerical and simulation results is obtained.

Keywords: Sallen-Key, fractance, stability, low-pass filter, analog filter

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22611 Investigating the Process Kinetics and Nitrogen Gas Production in Anammox Hybrid Reactor with Special Emphasis on the Role of Filter Media

Authors: Swati Tomar, Sunil Kumar Gupta

Abstract:

Anammox is a novel and promising technology that has changed the traditional concept of biological nitrogen removal. The process facilitates direct oxidation of ammonical nitrogen under anaerobic conditions with nitrite as an electron acceptor without the addition of external carbon sources. The present study investigated the feasibility of anammox hybrid reactor (AHR) combining the dual advantages of suspended and attached growth media for biodegradation of ammonical nitrogen in wastewater. The experimental unit consisted of 4 nos. of 5L capacity AHR inoculated with mixed seed culture containing anoxic and activated sludge (1:1). The process was established by feeding the reactors with synthetic wastewater containing NH4-H and NO2-N in the ratio 1:1 at HRT (hydraulic retention time) of 1 day. The reactors were gradually acclimated to higher ammonium concentration till it attained pseudo steady state removal at a total nitrogen concentration of 1200 mg/l. During this period, the performance of the AHR was monitored at twelve different HRTs varying from 0.25-3.0 d with increasing NLR from 0.4 to 4.8 kg N/m3d. AHR demonstrated significantly higher nitrogen removal (95.1%) at optimal HRT of 1 day. Filter media in AHR contributed an additional 27.2% ammonium removal in addition to 72% reduction in the sludge washout rate. This may be attributed to the functional mechanism of filter media which acts as a mechanical sieve and reduces the sludge washout rate many folds. This enhances the biomass retention capacity of the reactor by 25%, which is the key parameter for successful operation of high rate bioreactors. The effluent nitrate concentration, which is one of the bottlenecks of anammox process was also minimised significantly (42.3-52.3 mg/L). Process kinetics was evaluated using first order and Grau-second order models. The first-order substrate removal rate constant was found as 13.0 d-1. Model validation revealed that Grau second order model was more precise and predicted effluent nitrogen concentration with least error (1.84±10%). A new mathematical model based on mass balance was developed to predict N2 gas in AHR. The mass balance model derived from total nitrogen dictated significantly higher correlation (R2=0.986) and predicted N2 gas with least error of precision (0.12±8.49%). SEM study of biomass indicated the presence of the heterogeneous population of cocci and rod shaped bacteria of average diameter varying from 1.2-1.5 mm. Owing to enhanced NRE coupled with meagre production of effluent nitrate and its ability to retain high biomass, AHR proved to be the most competitive reactor configuration for dealing with nitrogen laden wastewater.

Keywords: anammox, filter media, kinetics, nitrogen removal

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22610 An Enzyme Technology - Metnin™ - Enables the Full Replacement of Fossil-Based Polymers by Lignin in Polymeric Composites

Authors: Joana Antunes, Thomas Levée, Barbara Radovani, Anu Suonpää, Paulina Saloranta, Liji Sobhana, Petri Ihalainen

Abstract:

Lignin is an important component in the exploitation of lignocellulosic biomass. It has been shown that within the next years, the yield of added-value lignin-based chemicals and materials will generate renewable alternatives to oil-based products (e.g. polymeric composites, resins and adhesives) and enhance the economic feasibility of biorefineries. In this paper, a novel technology for lignin valorisation (METNIN™) is presented. METNIN™ is based on the oxidative action of an alkaliphilic enzyme in aqueous alkaline conditions (pH 10-11) at mild temperature (40-50 °C) combined with a cascading membrane operation, yielding a collection of lignin fractions (from oligomeric down to mixture of tri-, di- and monomeric units) with distinct molecular weight distribution, low polydispersity and favourable physicochemical properties. The alkaline process conditions ensure the high processibility of crude lignin in an aqueous environment and the efficiency of the enzyme, yielding better compatibility of lignin towards targeted applications. The application of a selected lignin fraction produced by METNIN™ as a suitable lignopolyol to completely replace a commercial polyol in polyurethane rigid foam formulations is presented as a prototype. Liquid lignopolyols with a high lignin content were prepared by oxypropylation and their full utilization in the polyurethane rigid foam formulation was successfully demonstrated. Moreover, selected technical specifications of different foam demonstrators were determined, including closed cell count, water uptake and compression characteristics. These specifications are within industrial standards for rigid foam applications. The lignin loading in the lignopolyol was a major factor determining the properties of the foam. In addition to polyurethane foam demonstrators, other examples of lignin-based products related to resins and sizing applications will be presented.

Keywords: enzyme, lignin valorisation, polyol, polyurethane foam

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22609 Optimum Locations for Intercity Bus Terminals with the AHP Approach: Case Study of the City of Esfahan

Authors: Mehrdad Arabi, Ehsan Beheshtitabar, Bahador Ghadirifaraz, Behrooz Forjanizadeh

Abstract:

Interaction between human, location and activity defines space. In the framework of these relations, space is a container for current specifications in relations of the 3 mentioned elements. The change of land utility considered with average performance range, urban regulations, society requirements etc. will provide welfare and comfort for citizens. From an engineering view it is fundamental that choosing a proper location for a specific civil activity requires evaluation of locations from different perspectives. The debate of desirable establishment of municipal service elements in urban regions is one of the most important issues related to urban planning. In this paper, the research type is applicable based on goal, and is descriptive and analytical based on nature. Initially existing terminals in Esfahan are surveyed and then new locations are presented based on evaluated criteria. In order to evaluate terminals based on the considered factors, an AHP model is used at first to estimate weight of different factors and then existing and suggested locations are evaluated using Arc GIS software and AHP model results. The results show that existing bus terminals are located in fairly proper locations. Further results of this study suggest new locations to establish terminals based on urban criteria.

Keywords: Arc GIS, Esfahan city, optimum locations, terminals

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22608 Information Construction of Higher Education in Teaching Practice

Authors: Yang Meng, James L. Patnao

Abstract:

With the rapid development of information technology and the impact of the epidemic environment, the traditional teaching model can’t longer meet the requirements of the development of the times. The development of teaching mechanism is the inevitable trend of the future development of higher education. We must further promote the informatization of higher education in teaching practice, let modern information technology penetrate and practice in classroom teaching, and provide promising opportunities for the high-quality development of higher education. This article mainly through the distribution of questionnaires to teachers of colleges and universities, so as to understand the degree of informatization in the teaching of colleges and universities. And on the basis of domestic and foreign scholars' research on higher education informatization, it analyzes the existing problems, and finds the optimal solution based on the needs of education and teaching development. According to the survey results, most college teachers will use information technology in teaching practice, but the information technology teaching tools used by teachers are relatively simple, and most of them only use slides. In addition, backward informatization infrastructure and less informatization training are the main challenges facing the current teaching informatization construction. If colleges and universities can make good use of information technology and multimedia technology and combine it with traditional teaching, it will definitely promote the development of college education and further promote the modernization and informatization of higher education.

Keywords: higher education, teaching practice, informatization construction, e-education

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22607 Effects of Different Fiber Orientations on the Shear Strength Performance of Composite Adhesive Joints

Authors: Ferhat Kadioglu, Hasan Puskul

Abstract:

A composite material with carbon fiber and polymer matrix has been used as adherent for manufacturing adhesive joints. In order to evaluate different fiber orientations on joint performance, the adherents with the 0°, ±15°, ±30°, ±45° fiber orientations were used in the single lap joint configuration. The joints with an overlap length of 25 mm were prepared according to the ASTM 1002 specifications and subjected to tensile loadings. The structural adhesive used was a two-part epoxy to be cured at 70°C for an hour. First, mechanical behaviors of the adherents were measured using three point bending test. In the test, considerations were given to stress to failure and elastic modulus. The results were compared with theoretical ones using rule of mixture. Then, the joints were manufactured in a specially prepared jig, after a proper surface preparation. Experimental results showed that the fiber orientations of the adherents affected the joint performance considerably; the joints with ±45° adherents experienced the worst shear strength, half of those with 0° adherents, and in general, there was a great relationship between the fiber orientations and failure mechanisms. Delamination problems were observed for many joints, which were thought to be due to peel effects at the ends of the overlap. It was proved that the surface preparation applied to the adherent surface was adequate. For further explanation of the results, a numerical work should be carried out using a possible non-linear analysis.

Keywords: composite materials, adhesive bonding, bonding strength, lap joint, tensile strength

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22606 Rd-PLS Regression: From the Analysis of Two Blocks of Variables to Path Modeling

Authors: E. Tchandao Mangamana, V. Cariou, E. Vigneau, R. Glele Kakai, E. M. Qannari

Abstract:

A new definition of a latent variable associated with a dataset makes it possible to propose variants of the PLS2 regression and the multi-block PLS (MB-PLS). We shall refer to these variants as Rd-PLS regression and Rd-MB-PLS respectively because they are inspired by both Redundancy analysis and PLS regression. Usually, a latent variable t associated with a dataset Z is defined as a linear combination of the variables of Z with the constraint that the length of the loading weights vector equals 1. Formally, t=Zw with ‖w‖=1. Denoting by Z' the transpose of Z, we define herein, a latent variable by t=ZZ’q with the constraint that the auxiliary variable q has a norm equal to 1. This new definition of a latent variable entails that, as previously, t is a linear combination of the variables in Z and, in addition, the loading vector w=Z’q is constrained to be a linear combination of the rows of Z. More importantly, t could be interpreted as a kind of projection of the auxiliary variable q onto the space generated by the variables in Z, since it is collinear to the first PLS1 component of q onto Z. Consider the situation in which we aim to predict a dataset Y from another dataset X. These two datasets relate to the same individuals and are assumed to be centered. Let us consider a latent variable u=YY’q to which we associate the variable t= XX’YY’q. Rd-PLS consists in seeking q (and therefore u and t) so that the covariance between t and u is maximum. The solution to this problem is straightforward and consists in setting q to the eigenvector of YY’XX’YY’ associated with the largest eigenvalue. For the determination of higher order components, we deflate X and Y with respect to the latent variable t. Extending Rd-PLS to the context of multi-block data is relatively easy. Starting from a latent variable u=YY’q, we consider its ‘projection’ on the space generated by the variables of each block Xk (k=1, ..., K) namely, tk= XkXk'YY’q. Thereafter, Rd-MB-PLS seeks q in order to maximize the average of the covariances of u with tk (k=1, ..., K). The solution to this problem is given by q, eigenvector of YY’XX’YY’, where X is the dataset obtained by horizontally merging datasets Xk (k=1, ..., K). For the determination of latent variables of order higher than 1, we use a deflation of Y and Xk with respect to the variable t= XX’YY’q. In the same vein, extending Rd-MB-PLS to the path modeling setting is straightforward. Methods are illustrated on the basis of case studies and performance of Rd-PLS and Rd-MB-PLS in terms of prediction is compared to that of PLS2 and MB-PLS.

Keywords: multiblock data analysis, partial least squares regression, path modeling, redundancy analysis

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22605 Integrating HOTS Activities with Geogebra in Pre-Service Teachers' Preparation

Authors: Wajeeh Daher, Nimer Baya'a

Abstract:

High Order Thinking Skills (HOTS) are suggested today as essential for the cognitive development of students and as preparing them for real life skills. Teachers are encouraged to use HOTS activities in the classroom to help their students develop higher order skills and deep thinking. So it is essential to prepare pre-service teachers to write and use HOTS activities for their students. This paper describes a model for integrating HOTS activities with GeoGebra in pre-service teachers’ preparation. This model describes four aspects of HOTS activities and working with them: Activity components, preparation procedure, strategies and processes used in writing a HOTS activity and types of the HOTS activities. In addition, the paper describes the pre-service teachers' difficulties in preparing and working with HOTS activities, as well as their perceptions regarding the use of these activities and GeoGebra in the mathematics classroom. The paper also describes the contribution of a HOTS activity to pupils' learning of mathematics, where this HOTS activity was prepared and taught by one pre-service teacher.

Keywords: high order thinking skills, HOTS activities, pre-service teachers, professional development

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22604 A Continuous Boundary Value Method of Order 8 for Solving the General Second Order Multipoint Boundary Value Problems

Authors: T. A. Biala

Abstract:

This paper deals with the numerical integration of the general second order multipoint boundary value problems. This has been achieved by the development of a continuous linear multistep method (LMM). The continuous LMM is used to construct a main discrete method to be used with some initial and final methods (also obtained from the continuous LMM) so that they form a discrete analogue of the continuous second order boundary value problems. These methods are used as boundary value methods and adapted to cope with the integration of the general second order multipoint boundary value problems. The convergence, the use and the region of absolute stability of the methods are discussed. Several numerical examples are implemented to elucidate our solution process.

Keywords: linear multistep methods, boundary value methods, second order multipoint boundary value problems, convergence

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22603 Industrial Engineering Higher Education in Saudi Arabia: Assessing the Current Status

Authors: Mohammed Alkahtani, Ahmed El-Sherbeeny

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Industrial engineering is among engineering disciplines that have been introduced relatively recently to higher education in Saudi Arabian engineering colleges. The objective of this paper is to shed light on the history and status of IE higher education in different Saudi universities, including statistics comparing student enrollment and graduation in different Saudi public and private universities. This paper then proposes how industrial engineering programs could participate successfully in the Saudi Vision 2030. Finally, the authors show the results of a survey conducted on a number of IE students evaluating various academic and administrative aspects of the IE program at King Saud University.

Keywords: higher education, history, industrial engineering, Vision 2030

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22602 Feature Extraction of MFCC Based on Fisher-Ratio and Correlated Distance Criterion for Underwater Target Signal

Authors: Han Xue, Zhang Lanyue

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In order to seek more effective feature extraction technology, feature extraction method based on MFCC combined with vector hydrophone is exposed in the paper. The sound pressure signal and particle velocity signal of two kinds of ships are extracted by using MFCC and its evolution form, and the extracted features are fused by using fisher-ratio and correlated distance criterion. The features are then identified by BP neural network. The results showed that MFCC, First-Order Differential MFCC and Second-Order Differential MFCC features can be used as effective features for recognition of underwater targets, and the fusion feature can improve the recognition rate. Moreover, the results also showed that the recognition rate of the particle velocity signal is higher than that of the sound pressure signal, and it reflects the superiority of vector signal processing.

Keywords: vector information, MFCC, differential MFCC, fusion feature, BP neural network

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22601 Chemical Analysis of Available Portland Cement in Libyan Market Using X-Ray Fluorescence

Authors: M. A. Elbagermia, A. I. Alajtala, M. Alkerzab

Abstract:

This study compares the quality of different brands of Portland Cement (PC) available in Libyan market. The amounts of chemical constituents like SiO2, Al2O3, Fe2O3, CaO, MgO, SO3, and Lime Saturation Factor (LSF) were determined in accordance with Libyan (L.S.S) and Amrican (A.S.S) Standard Specifications. All the cement studies were found to be good for concrete work especially where no special property is required. The chemical and mineralogical analyses for studied clinker samples show that the dominant phases composition are C3S and C2S while the C3A and C4AF are less abundant.

Keywords: Portland cement, chemical composition, Libyan market, X-Ray fluorescence

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22600 Stability Analysis of Hossack Suspension Systems in High Performance Motorcycles

Authors: Ciro Moreno-Ramirez, Maria Tomas-Rodriguez, Simos A. Evangelou

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A motorcycle's front end links the front wheel to the motorcycle's chassis and has two main functions: the front wheel suspension and the vehicle steering. Up to this date, several suspension systems have been developed in order to achieve the best possible front end behavior, being the telescopic fork the most common one and already subjected to several years of study in terms of its kinematics, dynamics, stability and control. A motorcycle telescopic fork suspension model consists of a couple of outer tubes which contain the suspension components (coil springs and dampers) internally and two inner tubes which slide into the outer ones allowing the suspension travel. The outer tubes are attached to the frame through two triple trees which connect the front end to the main frame through the steering bearings and allow the front wheel to turn about the steering axis. This system keeps the front wheel's displacement in a straight line parallel to the steering axis. However, there exist alternative suspension designs that allow different trajectories of the front wheel with the suspension travel. In this contribution, the authors investigate an alternative front suspension system (Hossack suspension) and its influence on the motorcycle nonlinear dynamics to identify and reduce stability risks that a new suspension systems may introduce in the motorcycle dynamics. Based on an existing high-fidelity motorcycle mathematical model, the front end geometry is modified to accommodate a Hossack suspension system. It is characterized by a double wishbone design that varies the front end geometry on certain maneuverings and, consequently, the machine's behavior/response. It consists of a double wishbone structure directly attached to the chassis. In here, the kinematics of this system and its impact on the motorcycle performance/stability are analyzed and compared to the well known telescopic fork suspension system. The framework of this research is the mathematical modelling and numerical simulation. Full stability analyses are performed in order to understand how the motorcycle dynamics may be affected by the newly introduced front end design. This study is carried out by a combination of nonlinear dynamical simulation and root-loci methods. A modal analysis is performed in order to get a deeper understanding of the different modes of oscillation and how the Hossack suspension system affects them. The results show that different kinematic designs of a double wishbone suspension systems do not modify the general motorcycle's stability. The normal modes properties remain unaffected by the new geometrical configurations. However, these normal modes differ from one suspension system to the other. It is seen that the normal modes behaviour depends on various important dynamic parameters, such as the front frame flexibility, the steering damping coefficient and the centre of mass location.

Keywords: nonlinear mechanical systems, motorcycle dynamics, suspension systems, stability

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22599 The Role of Questioning Techniques in a Literature Classroom

Authors: Barbara Magallona

Abstract:

Given the observations between students who were active participants in a dialogue with their teacher and students who simply answered the teacher’s questions, the researcher will investigate the relationship between student-teacher dialogue in the classroom and the development of higher level thinking skills with an emphasis on the questioning techniques used by the teacher. The study posits the main question: What is the relationship between teachers’ questioning techniques and the development of students’ higher level thinking skills in a literature class (or in literature classes) in Xavier? The following are the study’s sub-questions: a) What types of questions do literature teachers at Xavier School ask? b) What types of responses do literature students at Xavier School give to teachers' questions? c) To what extent is the development of students' higher level thinking skills shown in teacher-student classroom dialogues in Xavier School's literature classroom? Since questioning techniques and student responses in the literature classroom form the core of this paper and in order to evaluate them, the study uses Andersen and Krathwohl’s revision of Harold Bloom’s Taxonomy of Educational Objectives. Teun van Dijk’s discourse-cognition-society triangle will be used as a theoretical framework to design and to guide the classroom interaction.

Keywords: discourse analysis, literature classroom, questioning techniques, secondary education

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22598 Path-Tracking Controller for Tracked Mobile Robot on Rough Terrain

Authors: Toshifumi Hiramatsu, Satoshi Morita, Manuel Pencelli, Marta Niccolini, Matteo Ragaglia, Alfredo Argiolas

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Automation technologies for agriculture field are needed to promote labor-saving. One of the most relevant problems in automated agriculture is represented by controlling the robot along a predetermined path in presence of rough terrain or incline ground. Unfortunately, disturbances originating from interaction with the ground, such as slipping, make it quite difficult to achieve the required accuracy. In general, it is required to move within 5-10 cm accuracy with respect to the predetermined path. Moreover, lateral velocity caused by gravity on the incline field also affects slipping. In this paper, a path-tracking controller for tracked mobile robots moving on rough terrains of incline field such as vineyard is presented. The controller is composed of a disturbance observer and an adaptive controller based on the kinematic model of the robot. The disturbance observer measures the difference between the measured and the reference yaw rate and linear velocity in order to estimate slip. Then, the adaptive controller adapts “virtual” parameter of the kinematics model: Instantaneous Centers of Rotation (ICRs). Finally, target angular velocity reference is computed according to the adapted parameter. This solution allows estimating the effects of slip without making the model too complex. Finally, the effectiveness of the proposed solution is tested in a simulation environment.

Keywords: the agricultural robot, autonomous control, path-tracking control, tracked mobile robot

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22597 The Role of Acoustical Design within Architectural Design in the Early Design Phase

Authors: O. Wright, N. Perkins, M. Donn, M. Halstead

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This research responded to anecdotal evidence that suggested inefficiencies within the Architect and Acoustician relationship may lead to ineffective acoustic design decisions.  The acoustician spoken to believed that he was approached too late in the design phase. The approached architect valued acoustical qualities, yet, struggled to interpret common measurement parameters. The preliminary investigation of these opinions indicated a gap in the current New Zealand Architectural discourse and currently informs the creation of a 2016 Master of Architecture (Prof) thesis research. Little meaningful information about acoustic intervention in the early design phase could be found from past literature. In the information that was sourced, authors focus on software as an incorporation tool without investigating why the flaws in the relationship originally exist. To further explore this relationship, a survey was designed. It underwent three phases to ensure its consistency, and was delivered to a group of 51 acousticians from one international Acoustics company. The results were then separated between New Zealand and off-shore to identify trends. The survey results suggest that 75% of acousticians meet the architect less than 5 times per project. Instead of regular contact, a mediated method is adopted though a mix of telecommunication and written reports. Acousticians tend to be introduced later into New Zealand building project than the corresponding off-shore building. This delay corresponds to an increase in remedial action for each of the building types in the survey except Auditoria and Office Buildings. 31 participants have had their specifications challenged by an architect. Furthermore, 71% of the acousticians believe that architects do not have the knowledge to understand why the acoustic specifications are in place. The issues raised in this investigation align to the colloquial evidence expressed by the two consultants. It identifies a larger gap in the industry were acoustics is remedially treated rather than identified as a possible design driver. Further research through design is suggested to understand the role of acoustics within architectural design and potential tools for its inclusion during, not after, the design process.

Keywords: architectural acoustics, early-design, interdisciplinary communication, remedial response

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22596 Using Learning Apps in the Classroom

Authors: Janet C. Read

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UClan set collaboration with Lingokids to assess the Lingokids learning app's impact on learning outcomes in classrooms in the UK for children with ages ranging from 3 to 5 years. Data gathered during the controlled study with 69 children includes attitudinal data, engagement, and learning scores. Data shows that children enjoyment while learning was higher among those children using the game-based app compared to those children using other traditional methods. It’s worth pointing out that engagement when using the learning app was significantly higher than other traditional methods among older children. According to existing literature, there is a direct correlation between engagement, motivation, and learning. Therefore, this study provides relevant data points to conclude that Lingokids learning app serves its purpose of encouraging learning through playful and interactive content. That being said, we believe that learning outcomes should be assessed with a wider range of methods in further studies. Likewise, it would be beneficial to assess the level of usability and playability of the app in order to evaluate the learning app from other angles.

Keywords: learning app, learning outcomes, rapid test activity, Smileyometer, early childhood education, innovative pedagogy

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22595 Technoeustress in Higher Education Teachers: A Study on Positive Stress

Authors: Ligia Nascimento, Manuela Faia Correia

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Nowadays, Information and Communication Technologies (ICT) are embedded in most professions. Technostress - or stress induced by the use of ICTs, has been studied in various sectors of activity and in different geographical areas, mainly from the perspective of its harmful impacts. In the context of work, the technological contexts capable of causing stress have been examined in-depth, as well as the type of individuals most likely to experience its negative effects. However, new lines of the research argue that the stress generated by the use of ICTs may not necessarily be detrimental (technodistress), admitting that, in contrast, and in addition, it may actually be beneficial to organizations and their employees (technoeustress). Any measures that succeed in reducing technodistress do not necessarily lead to the creation of technoeustress, justifying the study of this phenomenon in a focused and independent manner. Adopting the transactional model of stress as the basic theoretical framework, an ongoing research project aims to study technoeustress independently. Given the role played in the qualification and progress of society and the economy, it becomes particularly critical to care for the well-being of the higher education teacher. Particularly in recent times, when teleworking is prevalent, these professionals have made a huge, compulsive effort to adapt to a new teaching reality. Rather than limiting itself to mitigating adverse effects of ICT use, which featured earlier approaches, the present study seeks to understand how to activate the positive side of technostress in higher education teachers in order to obtain favorable personal and organizational outcomes from ICT use at work. The research model seeks to understand, upstream, the ICT characteristics that increase the perception of technoeustress among higher education teachers, studying the direct and moderating effects of individual and organizational variables and, downstream, the impacts that technoeustress has on job satisfaction and performance. This research contributes both to expanding the knowledge of the technostress phenomenon and to identify possible recommendations for management.

Keywords: higher education teachers, ICT, stress, technoeustress

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22594 Human Walking Vertical Force and Vertical Vibration of Pedestrian Bridge Induced by Its Higher Components

Authors: Masahiro Yoneda

Abstract:

The purpose of this study is to identify human walking vertical force by using FFT power spectrum density from the experimental acceleration data of the human body. An experiment on human walking is carried out on a stationary floor especially paying attention to higher components of dynamic vertical walking force. Based on measured acceleration data of the human lumbar part, not only in-phase component with frequency of 2 fw, 3 fw, but also in-opposite-phase component with frequency of 0.5 fw, 1.5 fw, 2.5 fw where fw is the walking rate is observed. The vertical vibration of pedestrian bridge induced by higher components of human walking vertical force is also discussed in this paper. A full scale measurement for the existing pedestrian bridge with center span length of 33 m is carried out focusing on the resonance phenomenon due to higher components of human walking vertical force. Dynamic response characteristics excited by these vertical higher components of human walking are revealed from the dynamic design viewpoint of pedestrian bridge.

Keywords: simplified method, human walking vertical force, higher component, pedestrian bridge vibration

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22593 Study of Ether Species Effects on Physicochemical Properties of Palm Oil Ether Monoesters as Novel Biodiesels

Authors: Hejun Guo, Shenghua Liu

Abstract:

Five palm oil ether monoesters utilized as novel biodiesels were synthesized and structurally identified in the paper. Investigation was made on the effect of ether species on physicochemical properties of the palm oil ether monoesters. The results showed that density, kinematic viscosity, smoke point, and solidifying point increase linearly with their CH2 group number in certain relationships. Cetane number is enhanced whereas heat value decreases linearly with CH2 group number. In addition, the influencing regularities of volumetric content of the palm oil ether monoesters on the fuel properties were also studied when the ether monoesters are used as diesel fuel additives.

Keywords: biodiesel, palm oil ether monoester, ether species, physicochemical property

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22592 Smartphones: Tools for Enhancing Teaching in Nigeria’s Higher Institutions

Authors: Ma'amun Muhammed

Abstract:

The ability of smartphones in enhancing communication, providing access to business and serving as a pool for information retrieval has a far reaching and potentially beneficial impacts on enhancing teaching in higher institutions in the developing countries like Nigeria. Nigeria as one of the fast growing economies in Africa, whose citizens patronize smartphones can utilize this opportunity by inculcating the culture of using smartphones not only for communication, business transaction, banking etc. but also for enhancing teaching in the higher institutions. Smartphones have become part and parcel of our lives, particularly among young people. The primary objective of this paper is to ascertain the use of smartphones in enhancing teaching in Nigeria’s higher institutions, to achieve this, content analysis was used thoroughly. This paper examines the opportunities offered by smartphones to the students of higher institutions of learning, the challenges being faced by lecturers of these institutions in classrooms. Lastly, it offers solution on how some of these critical challenges will be overcame, so as to utilize the technology of these devices.

Keywords: communication, information retrieval, mobile phone, smartphones teaching

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22591 Democratisation of Teaching and Learning in Higher Education

Authors: Jane Ebele Iloanya

Abstract:

The introduction of the learning outcome approach in contemporary curriculum design and instruction, has brought student–centered education to the fore. In teacher –centered teaching and learning, the teacher transfers knowledge to the students, who are always at the receiving end. The teacher is assumed to know it all and hardly trusts the knowledge of the students. Teacher-centered education places emphasis on the supremacy of the teacher over the students who should ideally, be able to dialogue with the teacher. The paper seeks to examine the issue of democratisation of the teaching and learning process in Institutions of Higher Learning in Botswana. Botswana is a landlocked country in Southern Africa, with a total population of about two million people. In 1977, Botswana’s First National Policy on Education was unveiled. This came eleven years after the country gained independence from Great Britain. The philosophy which informed the 1977 Education Policy was “Social Harmony”. The philosophy of social harmony has four main principles: Unity, Development, Democracy and Self- Reliance. These principles were meant to permeate all aspects of lives of the people of Botswana, including, the issue of how teaching and learning is conducted in Botswana’s institutions of higher learning. This paper will examine the practicalisation of the principle of democracy in teaching and learning at higher education level in Botswana. It will in particular, discuss the issue of students’ participation and engagement in the teaching and learning process. The following questions will be addressed: 1.Are students involved in planning the curriculum? 2.How engaged are the students in the teaching and learning process? 3.How democratic are the teachers in terms of students’ rights and privileges? A mixed–method approach will be adopted in this study. Questionnaires will be distributed to the students to elicit their views on the practicalisation of the principle of democracy at the higher education level. Semi-structured interview questions will be administered in order to collect information from the lecturers on the issue of democratisation of teaching and learning at the higher education level in Botswana. In addition, relevant and related literature will be reviewed to augment collected data. The study will focus on three tertiary institutions in Gaborone, the capital city of Botswana. Currently, there are ten tertiary institutions in Gaborone; both privately and government owned. The outcome of this study will add to the existing body of knowledge on the issue of the practicalisation of democracy at the higher education level in Botswana. This research is therefore relevant in helping to find out if democratisation of teaching and learning has been realised in Botswana’s Institutions of higher learning. It is important to examine Botswana’s national policy on education in this way to ascertain if it has been effective in giving the country’s education system that democratic element, which is essential for a student-centered approach to the teaching and learning process.

Keywords: democratisation, higher education, learning, teaching

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22590 Control Law Design of a Wheeled Robot Mobile

Authors: Ghania Zidani, Said Drid, Larbi Chrifi-Alaoui, Abdeslam Benmakhlouf, Souad Chaouch

Abstract:

In this paper, we focus on the study for path tracking control of unicycle-type Wheeled Mobile Robots (WMR), by applying the Backstepping technic. The latter is a relatively new technic for nonlinear systems. To solve the problem of constraints nonholonomics met in the path tracking of such robots, an adaptive Backstepping based nonlinear controller is developed. The stability of the controller is guaranteed, using the Lyapunov theory. Simulation results show that the proposed controller achieves the objective and ensures good path tracking.

Keywords: Backstepping control, kinematic and dynamic controllers, Lyapunov methods, nonlinear control systems, Wheeled Mobile Robot (WMR).

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22589 Estimating Housing Prices Using Automatic Linear Modeling in the Metropolis of Mashhad, Iran

Authors: Mohammad Rahim Rahnama

Abstract:

Market-transaction price for housing is the main criteria for determining municipality taxes and is determined and announced on an annual basis. Of course, there is a discrepancy between the actual value of transactions in the Bureau of Finance (P for short) or municipality (P´ for short) and the real price on the market (P˝). The present research aims to determine the real price of housing in the metropolis of Mashhad and to pinpoint the price gap with those of the aforementioned apparatuses and identify the factors affecting it. In order to reach this practical objective, Automatic Linear Modeling, which calls for an explanatory research, was utilized. The population of the research consisted of all the residential units in Mashhad, from which 317 residential units were randomly selected. Through cluster sampling, out of the 170 income blocks defined by the municipality, three blocks form high-income (Kosar), middle-income (Elahieh), and low-income (Seyyedi) strata were surveyed using questionnaires during February and March of 2015 and the information regarding the price and specifications of residential units were gathered. In order to estimate the effect of various factors on the price, the relationship between independent variables (8 variables) and the dependent variable of the housing price was calculated using Automatic Linear Modeling in SPSS. The results revealed that the average for housing price index is 788$ per square meter, compared to the Bureau of Finance’s prices which is 10$ and that of municipality’s which is 378$. Correlation coefficient among dependent and independent variables was calculated to be R²=0.81. Out of the eight initial variables, three were omitted. The most influential factor affecting the housing prices is the quality of Quality of construction (Ordinary, Full, Luxury). The least important factor influencing the housing prices is the variable of number of sides. The price gap between low-income (Seyyedi) and middle-income (Elahieh) districts was not confirmed via One-Way ANOVA but their gap with the high-income district (Kosar) was confirmed. It is suggested that city be divided into two low-income and high-income sections, as opposed three, in terms of housing prices.

Keywords: automatic linear modeling, housing prices, Mashhad, Iran

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22588 The Relationship of Lean Management Principles with Lean Maturity Levels: Multiple Case Study in Manufacturing Companies

Authors: Alexandre D. Ferraz, Dario H. Alliprandini, Mauro Sampaio

Abstract:

Companies and other institutions are constantly seeking better organizational performance and greater competitiveness. In order to fulfill this purpose, there are many tools, methodologies and models for increasing performance. However, the Lean Management approach seems to be the most effective in terms of achieving a significant improvement in productivity relatively quickly. Although Lean tools are relatively easy to understand and implement in different contexts, many organizations are not able to transform themselves into 'Lean companies'. Most of the efforts in its implementation have shown single benefits, failing to achieve the desired impact on the performance of the overall enterprise system. There is also a growing perception of the importance of management in Lean transformation, but few studies have empirically investigated and described the 'Lean Management'. In order to understand more clearly the ideas that guide Lean Management and its influence on the maturity level of the production system, the objective of this research is analyze the relationship between the Lean Management principles and the Lean maturity level in the organizations. The research also analyzes the principles of Lean Management and its relationship with the 'Lean culture' and the results obtained. The research was developed using the case study methodology. Three manufacturing units of a German multinational company from industrial automation segment, located in different countries were studied, in order to have a better comparison between the practices and the level of maturity in the implementation. The primary source of information was the application of a research questionnaire based on the theoretical review. The research showed that higher the level of Lean Management principles, higher are the Lean maturity level, the Lean culture level, and the level of Lean results obtained in the organization. The research also showed that factors such as time for application of Lean concepts and company size were not determinant for the level of Lean Management principles and, consequently, for the level of Lean maturity in the organization. The characteristics of the production system showed much more influence in different evaluated aspects. The present research also left recommendations for the managers of the plants analyzed and suggestions for future research.

Keywords: lean management, lean principles, lean maturity level, lean manufacturing

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22587 High Performance Methyl Orange Capture on Magnetic Nanoporous MCM-41 Prepared by Incipient Wetness Impregnation Method

Authors: Talib M. Albayati, Omar S. Mahdy, Ghanim M. Alwan

Abstract:

This work is aimed to prepare magnetic nanoporous material Fe/MCM-41 and study its Physical characterization in order to enhance the magnetic properties for study the operating conditions on separation efficiency of methyl orange (MO) from wastewater by adsorption process. The experimental results are analysed to select the best operating conditions for different studied parameters which were obtained for both adsorbents mesoporous material samples MCM-41 and magnetic Fe/MCM-41 as follow: constant temperature (20 ºC), pH: (2) adsorbent dosage (0.03 gm), contact time (10 minute) and concentrations (30 mg/L). The results are demonstrated that the adsorption processes can be well fitted by the Langmuir isotherm model for pure MCM-41 with a higher correlation coefficient (0.999) and fitted by the freundlich isotherm model for magnetic Fe/MCM-41 with a higher correlation coefficient of (0.994).

Keywords: adsorption, nanoporous materials, mcm-41, magnetic material, wastewater, orange, wastewater

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22586 Knowledge Management for Competitiveness and Performances in Higher Educational Institutes

Authors: Jeyarajan Sivapathasundram

Abstract:

Knowledge management has been recognised as an emerging factor for being competitive among institutions and performances in firms. As such, being recognised as knowledge rich institution, higher education institutes have to be recognised knowledge management based resources for achieving competitive advantages. Present research picked result out of postgraduate research conducted in knowledge management at non-state higher educational institutes of Sri Lanka. Besides, the present research aimed to discover knowledge management for competition and firm performances of higher educational institutes out of the result produced by the postgraduate study. Besides, the results are found in a pair that developed out of knowledge management practices and the reason behind the existence of the practices. As such, the present research has developed a filter to pick the pairs that satisfy its condition of competition and performance of the firm. As such, the pair, such as benchmarking is practised to be ethically competing through conducting courses. As the postgraduate research tested results of foreign researches in a qualitative paradigm, the finding of the present research are generalise fact for knowledge management for competitiveness and performances in higher educational institutes. Further, the presented research method used attributes which explain competition and performance in its filter to discover the pairs relevant to competition and performances. As such, the fact in regards to knowledge management for competition and performances in higher educational institutes are presented in the publication that the presentation is out of the generalised result. Therefore, knowledge management for competition and performance in higher educational institutes are generalised.

Keywords: competition in and among higher educational institutes, performances of higher educational institutes, noun based filtering, production out of generalisation of a research

Procedia PDF Downloads 113