Search results for: uniaxial tensile test
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10082

Search results for: uniaxial tensile test

8702 Numerical Modeling of Determination of in situ Rock Mass Deformation Modulus Using the Plate Load Test

Authors: A. Khodabakhshi, A. Mortazavi

Abstract:

Accurate determination of rock mass deformation modulus, as an important design parameter, is one of the most controversial issues in most engineering projects. A 3D numerical model of standard plate load test (PLT) using the FLAC3D code was carried to investigate the mechanism governing the test process. Five objectives were the focus of this study. The first goal was to employ 3D modeling in the interpretation of PLT conducted at the Bazoft dam site, Iran. The second objective was to investigate the effect of displacements measuring depth from the loading plates on the calculated moduli. The magnitude of rock mass deformation modulus calculated from PLT depends on anchor depth, and in practice, this may be a cause of error in the selection of realistic deformation modulus for the rock mass. The third goal of the study was to investigate the effect of testing plate diameter on the calculated modulus. Moreover, a comparison of the calculated modulus from ISRM formula, numerical modeling and calculated modulus from the actual PLT carried out at right abutment of the Bazoft dam site was another objective of the study. Finally, the effect of plastic strains on the calculated moduli in each of the loading-unloading cycles for three loading plates was investigated. The geometry, material properties, and boundary conditions on the constructed 3D model were selected based on the in-situ conditions of PLT at Bazoft dam site. A good agreement was achieved between numerical model results and the field tests results.

Keywords: deformation modulus, numerical model, plate loading test, rock mass

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8701 Temperature Dependence of Relative Permittivity: A Measurement Technique Using Split Ring Resonators

Authors: Sreedevi P. Chakyar, Jolly Andrews, V. P. Joseph

Abstract:

A compact method for measuring the relative permittivity of a dielectric material at different temperatures using a single circular Split Ring Resonator (SRR) metamaterial unit working as a test probe is presented in this paper. The dielectric constant of a material is dependent upon its temperature and the LC resonance of the SRR depends on its dielectric environment. Hence, the temperature of the dielectric material in contact with the resonator influences its resonant frequency. A single SRR placed between transmitting and receiving probes connected to a Vector Network Analyser (VNA) is used as a test probe. The dependence of temperature between 30 oC and 60 oC on resonant frequency of SRR is analysed. Relative permittivities ‘ε’ of test samples for different temperatures are extracted from a calibration graph drawn between the relative permittivity of samples of known dielectric constant and their corresponding resonant frequencies. This method is found to be an easy and efficient technique for analysing the temperature dependent permittivity of different materials.

Keywords: metamaterials, negative permeability, permittivity measurement techniques, split ring resonators, temperature dependent dielectric constant

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8700 Avoidance of Brittle Fracture in Bridge Bearings: Brittle Fracture Tests and Initial Crack Size

Authors: Natalie Hoyer

Abstract:

Bridges in both roadway and railway systems depend on bearings to ensure extended service life and functionality. These bearings enable proper load distribution from the superstructure to the substructure while permitting controlled movement of the superstructure. The design of bridge bearings, according to Eurocode DIN EN 1337 and the relevant sections of DIN EN 1993, increasingly requires the use of thick plates, especially for long-span bridges. However, these plate thicknesses exceed the limits specified in the national appendix of DIN EN 1993-2. Furthermore, compliance with DIN EN 1993-1-10 regulations regarding material toughness and through-thickness properties necessitates further modifications. Consequently, these standards cannot be directly applied to the selection of bearing materials without supplementary guidance and design rules. In this context, a recommendation was developed in 2011 to regulate the selection of appropriate steel grades for bearing components. Prior to the initiation of the research project underlying this contribution, this recommendation had only been available as a technical bulletin. Since July 2023, it has been integrated into guideline 804 of the German railway. However, recent findings indicate that certain bridge-bearing components are exposed to high fatigue loads, which necessitate consideration in structural design, material selection, and calculations. Therefore, the German Centre for Rail Traffic Research called a research project with the objective of defining a proposal to expand the current standards in order to implement a sufficient choice of steel material for bridge bearings to avoid brittle fracture, even for thick plates and components subjected to specific fatigue loads. The results obtained from theoretical considerations, such as finite element simulations and analytical calculations, are validated through large-scale component tests. Additionally, experimental observations are used to calibrate the calculation models and modify the input parameters of the design concept. Within the large-scale component tests, a brittle failure is artificially induced in a bearing component. For this purpose, an artificially generated initial defect is introduced at the previously defined hotspot into the specimen using spark erosion. Then, a dynamic load is applied until the crack initiation process occurs to achieve realistic conditions in the form of a sharp notch similar to a fatigue crack. This initiation process continues until the crack length reaches a predetermined size. Afterward, the actual test begins, which requires cooling the specimen with liquid nitrogen until a temperature is reached where brittle fracture failure is expected. In the next step, the component is subjected to a quasi-static tensile test until failure occurs in the form of a brittle failure. The proposed paper will present the latest research findings, including the results of the conducted component tests and the derived definition of the initial crack size in bridge bearings.

Keywords: bridge bearings, brittle fracture, fatigue, initial crack size, large-scale tests

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8699 Hydraulic Conductivity Prediction of Cement Stabilized Pavement Base Incorporating Recycled Plastics and Recycled Aggregates

Authors: Md. Shams Razi Shopnil, Tanvir Imtiaz, Sabrina Mahjabin, Md. Sahadat Hossain

Abstract:

Saturated hydraulic conductivity is one of the most significant attributes of pavement base course. Determination of hydraulic conductivity is a routine procedure for regular aggregate base courses. However, in many cases, a cement-stabilized base course is used with compromised drainage ability. Traditional hydraulic conductivity testing procedure is a readily available option which leads to two consequential drawbacks, i.e., the time required for the specimen to be saturated and extruding the sample after completion of the laboratory test. To overcome these complications, this study aims at formulating an empirical approach to predicting hydraulic conductivity based on Unconfined Compressive Strength test results. To do so, this study comprises two separate experiments (Constant Head Permeability test and Unconfined Compressive Strength test) conducted concurrently on a specimen having the same physical credentials. Data obtained from the two experiments were then used to devise a correlation between hydraulic conductivity and unconfined compressive strength. This correlation in the form of a polynomial equation helps to predict the hydraulic conductivity of cement-treated pavement base course, bypassing the cumbrous process of traditional permeability and less commonly used horizontal permeability tests. The correlation was further corroborated by a different set of data, and it has been found that the derived polynomial equation is deemed to be a viable tool to predict hydraulic conductivity.

Keywords: hydraulic conductivity, unconfined compressive strength, recycled plastics, recycled concrete aggregates

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8698 Effect of Video-Based Instructional Strategy on Junior Secondary School Students' Academic Achievement in Social Studies in Ondo State, Nigeria

Authors: Abidoye James Alabi

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This study investigated the effect of video-based instructional strategy on junior secondary school academic achievement in social studies. The influence of gender on the academic achievement of student taught with video-based instructional strategy was also examined. The study adopted a pre-test and pro-test control group quasi-experimental design. Simple random sampling technique was used to select 40 students from two schools in Akure town in Ondo State. The researcher developed instructional video package on social studies concept which was used as treatment instrument for the experimental group while the control group was exposed to conventional teaching method. The instruments used in this study are social studies achievement test and instructional video package (IVP). T-test statistic was used to analyse the hypotheses. The findings revealed that experimental group performed better than the control group. It was also shown that gender has no significant effect on students’ academic achievement when exposed to an instructional video package. It was recommended that appropriate training and workshop should be organized by the government for the social studies teachers for effective use of instructional video package in order to enhance teachers productivities and learning among students in secondary schools.

Keywords: instructional video package, conventional teaching method, social studies, junior secondary school

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8697 Attitude of Nigerian Women Towards the Prevention of Sexually Transmission of HIV

Authors: Akanle Florence Foluso, Ola Tolulope Monisola, Oludare Abosede Abiola

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The study investigated the attitude of married women toward the prevention of HIV in heterosexual relationships. A population-based survey was conducted using a total number of 1,400 women aged 24-45 years. The women were randomly selected from the general population. Mohamed Talabi and William's attitudinal scale was used to measure the attitude of women towards HIV and its prevention. The questionnaire had a reliability coefficient of 0.85. Frequency contents percentage woe used to describe the data while Pearson Product Moment Correlation, Chi-Square and test were used to test all the hypotheses raised. All hypotheses were tested at a 0.05 level of significance. The study revealed that the majority of women unknowingly practice risky behaviors, which could promote this transmission. They neither insist on a condom to have sex even when their husband has many other sexual partners apart from them. Others felt they could not be assertive in telling their husband to seek medical HIV testing or get their sex partner to seek medical treatment. Many have never seen a female condom or avoid sex to prevent HIV. Many believe it would be embarrassing to get an HIV antibody test. Many women will not avoid sex if there is a slight chance that their partner might have this and would not be able to insist that a condom be used if they were to have sex. It was recommended that there is a need to understand the HIV risk from a woman’s perspective.

Keywords: women, HIV, men, attitude of women, sexual partner

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8696 Investigating the Effect of Metaphor Awareness-Raising Approach on the Right-Hemisphere Involvement in Developing Japanese Learners’ Knowledge of Different Degrees of Politeness

Authors: Masahiro Takimoto

Abstract:

The present study explored how the metaphor awareness-raising approach affects the involvement of the right hemisphere in developing EFL learners’ knowledge regarding the different degrees of politeness embedded within different request expressions. The present study was motivated by theoretical considerations regarding the conceptual projection and the metaphorical idea of politeness is distance, as proposed; this study applied these considerations to develop Japanese learners’ knowledge regarding the different politeness degrees and to explore the connection between the metaphorical concept projection and right-hemisphere dominance. Japanese EFL learners do not know certain language strategies (e.g., English requests can be mitigated with biclausal downgraders, including the if-clause with past-tense modal verbs) and have difficulty adjusting the politeness degrees attached to request expressions according to situations. The present study used a pre/post-test design to reaffirm the efficacy of the cognitive technique and its connection to right-hemisphere involvement by mouth asymmetry technique. Mouth asymmetry measurement has been utilized because speech articulation, normally controlled mainly by one side of the brain, causes muscles on the opposite side of the mouth to move more during speech production. The present research did not administer the delayed post-test because it emphasized determining whether metaphor awareness-raising approaches for developing EFL learners’ pragmatic proficiency entailed right-hemisphere activation. Each test contained an acceptability judgment test (AJT) along with a speaking test in the post-test. The study results show that the metaphor awareness-raising group performed significantly better than the control group with regard to acceptability judgment and speaking tests post-test. These data revealed that the metaphor awareness-raising approach could promote L2 learning because it aided input enhancement and concept projection; through these aspects, the participants were able to comprehend an abstract concept: the degree of politeness in terms of the spatial concept of distance. Accordingly, the proximal-distal metaphor enabled the study participants to connect the newly spatio-visualized concept of distance to the different politeness degrees attached to different request expressions; furthermore, they could recall them with the left side of the mouth being wider than the right. This supported certain findings from previous studies that indicated the possible involvement of the brain's right hemisphere in metaphor processing.

Keywords: metaphor awareness-raising, right hemisphere, L2 politeness, mouth asymmetry

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8695 E-learning: An Effective Approach for Enhancing Social and Behavior Change Communication Capacity in Bangladesh

Authors: Mohammad K. Abedin, Mohammad Shahjahan, Zeenat Sultana, Tawfique Jahan, Jesmin Akter

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To strengthen social and behavior change communication (SBCC) capacity of Ministry of Health and Family Welfare (MoHFW) of the Government of Bangladesh, BCCP/BKMI developed two eLearning courses providing opportunities for professional development of SBCC Program Managers who have no access to training or refreshers training. The two eLearning courses – Message and Material Development (MMD) and Monitoring and Evaluation (MandE) of SBCC programs – went online in September 2015, where all users could register their participation so results could be monitored. Methodology: To assess the uses of these courses a randomly selected sample was collected to run a pre and post-test analyses and a phone survey were conducted. Systematic random sampling was used to select a sample of 75 MandE and 25 MMD course participants from a sampling frame of 179 and 51 respectively. Results: As of September 2016, more than 179 learners have completed the MandE course, and 49 learners have completed the MMD course. The users of these courses are program managers, university faculty members, and students. Encouraging results were revealed from the analysis of pre and post-test scores and a phone survey three months after course completion. Test scores suggested a substantial increase in knowledge. The pre-test scores findings suggested that about 19% learners scored high on the MandE. The post-test scores finding indicated a high score (92%) of the sample across 4 modules of MandE. For MMD course in pre-test scoring, 30% of the learners scored high, and 100% scored high at the post-test. It was found that all the learners in the phone survey have discussed the courses. Most of the sharing occurred with colleagues and friends, usually through face to face (70%) interaction. The learners reported that they did recommend the two courses to concerned people. About 67% MandE and 76% MMD learners stated that the concepts that they had to learn during the course were put into practice in their work settings. The respondents for both MandE and MMD courses have provided a valuable set of suggestions that would further strengthen the courses. Conclusions: The study showed that the initiative offered ample opportunities to build capacity in various ways in which the eLearning courses were used. It also highlighted the importance of scaling up these efforts to further strengthen the outcomes.

Keywords: e-learning course, message & material development, monitoring & evaluation, social and behavior change communication

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8694 An Operators’ Real-sense-based Fire Simulation for Human Factors Validation in Nuclear Power Plants

Authors: Sa-Kil Kim, Jang-Soo Lee

Abstract:

On March 31, 1993, a severe fire accident took place in a nuclear power plant located in Narora in North India. The event involved a major fire in the turbine building of NAPS unit-1 and resulted in a total loss of power to the unit for 17 hours. In addition, there was a heavy ingress of smoke in the control room, mainly through the intake of the ventilation system, forcing the operators to vacate the control room. The Narora fire accident provides us lessons indicating that operators could lose their mind and predictable behaviors during a fire. After the Fukushima accident, which resulted from a natural disaster, unanticipated external events are also required to be prepared and controlled for the ultimate safety of nuclear power plants. From last year, our research team has developed a test and evaluation facility that can simulate external events such as an earthquake and fire based on the operators’ real-sense. As one of the results of the project, we proposed a unit real-sense-based facility that can simulate fire events in a control room for utilizing a test-bed of human factor validation. The test-bed has the operator’s workstation shape and functions to simulate fire conditions such as smoke, heat, and auditory alarms in accordance with the prepared fire scenarios. Furthermore, the test-bed can be used for the operators’ training and experience.

Keywords: human behavior in fire, human factors validation, nuclear power plants, real-sense-based fire simulation

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8693 The Effects of Orientation on Energy and Plasticity of Metallic Crystalline-Amorphous Interface

Authors: Ehsan Alishahi, Chuang Deng

Abstract:

Commercial applications of bulk metallic glasses (BMGs) were restricted due to the sudden brittle failure mode which was the main drawback in these new class of materials. Therefore, crystalline-amorphous (C-A) composites were introduced as a toughening strategy in BMGs. In spite of numerous researches in the area of metallic C-A composites, the fundamental structure-property relation in these composites that are not exactly known yet. In this study, it is aimed to investigate the fundamental properties of crystalline-amorphous interface in a model system of Cu/CuZr by using molecular dynamics simulations. Several parameters including interface energy and mechanical properties were investigated by means of atomic models and employing Embedded Atom Method (EAM) potential function. It is found that the crystalline-amorphous interfacial energy weakly depends on the orientation of the crystalline layer, which is in stark contrast to that in a regular crystalline grain boundary. Additionally, the results showed that the interface controls the yielding of the crystalline-amorphous composites during uniaxial tension either by serving as sources for dislocation nucleation in the crystalline layer or triggering local shear transformation zones in amorphous layer. The critical resolved shear stress required to nucleate the first dislocation is also found to strongly depend on the crystalline orientation. Furthermore, it is found that the interaction between dislocations and shear localization at the crystalline-amorphous interface oriented in different directions can lead to a change in the deformation mode. For instance, while the dislocation and shear banding are aligned to each other in {0 0 1} interface plane, the misorientation angle between these failure mechanisms causing more homogeneous deformation in {1 1 0} and {1 1 1} crystalline-amorphous interfaces. These results should help clarify the failure mechanism of crystalline-amorphous composites under various loading conditions.

Keywords: crystalline-amorphous, composites, orientation, plasticity

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8692 Stress Corrosion Cracking, Parameters Affecting It, Problems Caused by It and Suggested Methods for Treatment: State of the Art

Authors: Adnan Zaid

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Stress corrosion cracking (SCC) may be defined as a degradation of the mechanical properties of a material under the combined action of a tensile stress and corrosive environment of the susceptible material. It is a harmful phenomenon which might cause catastrophic fracture without a sign of prior warning. In this paper, the stress corrosion cracking, SCC, process, the parameters affecting it, and the different damages caused by it are given and discussed. Utilization of shot peening as a mean of enhancing the resistance of materials to SCC is given and discussed. Finally, a method for improving materials resistance to SCC by grain refining its structure by some refining elements prior to usage is suggested.

Keywords: stress corrosion cracking, parameters, damages, treatment methods

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8691 Feature Extraction and Classification Based on the Bayes Test for Minimum Error

Authors: Nasar Aldian Ambark Shashoa

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Classification with a dimension reduction based on Bayesian approach is proposed in this paper . The first step is to generate a sample (parameter) of fault-free mode class and faulty mode class. The second, in order to obtain good classification performance, a selection of important features is done with the discrete karhunen-loeve expansion. Next, the Bayes test for minimum error is used to classify the classes. Finally, the results for simulated data demonstrate the capabilities of the proposed procedure.

Keywords: analytical redundancy, fault detection, feature extraction, Bayesian approach

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8690 Polyphytopharmaca Improving Asthma Control Test Value, Biomarker (Eosinophils and Malondialdehyde): Quasi Experimental Test in Patients with Asthma

Authors: Andri Andri, Susanthy Djajalaksana, Iin Noor Chozin

Abstract:

Background: Despite advances in asthma therapies, a proportion of patients with asthma continue to have difficulty in gaining adequate asthma control. Complex immunological mechanisms and oxidative stress affect this condition, including the role of malondialdehyde (MDA) as a marker of inflammation. This research aimed to determine the effect of polyphytopharmaca administration on the value of asthma control test (ACT), blood eosinophils level and markers of MDA serum inflammation in patients with asthma. Method: Quasi experimental approach was conducted toward 15 stable asthma patients who were not fully controlled in outpatient pulmonary clinic, Public Hospital of Dr. Saiful Anwar Malang. Assessments of ACT values, eosinophil levels, and serum MDA levels were carried out before and after administration of polyphytopharmaca which contained a combination of 100 mg Nigella sativa extract, Kleinhovia hospita 100 mg, Curcuma xanthorrhiza 75 mg, and Ophiocephalus striatus 100 mg, three times daily with two capsules for 12 weeks. The ACT value was determined by the researcher by asking the patient directly, blood eosinophil levels were calculated by analyzing blood type counts, and serum MDA levels were detected by the qPCR method. Result: There was a significant enhancement of ACT value (18.07 ± 2.57 to 22.06 ± 1.83, p = 0.001) (from 60% uncontrolled ACT to 93.3% controlled ACT), a significant decrease in blood eosinophils levels (653.15 ± 276.15 pg/mL to 460.66 ± 202.04 pg/mL, p = 0.038), and decreased serum MDA levels (109.64 ± 53.77 ng / ml to 78.68 ± 64.92 ng/ml, p = 0.156). Conclusion: Administration of polyphytopharmaca can increase ACT value, decrease blood eosinophils levels and reduce MDA serum in stable asthma patients who are not fully controlled.

Keywords: asthma control test, eosinophils levels, malondialdehyde, polyphytopharmaca

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8689 Differential Item Functioning in the Vocabulary Test of Grade 7 Students in Public and Private Schools

Authors: Dave Kenneth Tayao Cayado, Carlo P. Magno

Abstract:

The most common source of bias detected are those of gender and socioeconomic status. The present study investigated the Differential Item Functioning (DIF) or item bias between public and private school students in a vocabulary test. Studies on DIF were expanded by using the type of school as a source of bias. There were 200 participants in this study. 100 came from a public secondary school and 100 came from a private secondary school. The vocabulary skills of students were measured using a standardized vocabulary test for grade 7 students. Using DIF, specifically the Rasch-Welch approach, it was found that out of 24 items, 12 were biased for a specific group. The vocabulary skills on the use of slang, idiomatic expression, personification, collocations, and partitive relations were biased for private schools while the use of slang and homonymous words were biased for public school students. The analysis debunked the trend that private school students are outperforming public school students in terms of academic achievement. It was revealed that there are some competencies that private school students are having difficulty and vice versa.

Keywords: differential item functioning, item bias, public school students, private school students, vocabulary

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8688 The Effects of Collaborative Reflection and Class Observation on Improving the Quality of Teacher-Training Courses

Authors: Somayeh Sharifi

Abstract:

The purpose of this study is to investigate the effects of collaborative reflection and class observation on improving the quality of teacher training courses and the students reading comprehension skills. 13 inexperienced English teachers teaching elementary courses that were at the same level of proficiency were chosen. Thirteen participants were allocated in two groups, with 7 teachers in the experimental group and the other 6 teachers in the control group. Since two groups were not selected randomly, this study is a form of quasi-experimental research. In addition to a 3-day teacher training course for both groups, teachers in experimental group recorded and observed 20 sessions of their own classes and 30 sessions of experienced teachers’ class and participated in 12 meetings -3 month once a week- in which teachers shared any event that they found interesting during observations and their own teaching and compare it with strategies that they learned in teacher training courses. In contrast, the control group did not engage in any process of observation and collaboration. In order to test students' performance in English before and after the treatment, a Key English Test (KET) was employed to check students' reading skill. The result of the test shows that there is not a significant difference in mean of scores in KET pretest in and, since they are close to each other. However by considering mean and median of posttest in both classes we perceive that although both control and experimental group students' proficiency in English enhanced, there was a significant difference in experimental group students' final scores before and after treatment.

Keywords: collaborative reflection, reading comprehension, teacher training courses, key English test (KET)

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8687 Effect of Cooperative Learning Strategy on Mathematics Achievement and Retention of Senior Secondary School Students of Different Ability Levels in Taraba State, Nigeria

Authors: Onesimus Bulus Shiaki

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The study investigated the effect of cooperative learning strategy on mathematics achievement and retention among senior secondary school students of different abilities in Taraba State Nigeria. Cooperative learning strategy could hopefully contribute to students’ achievement which will spur the teachers to develop strategies for better learning. The quasi-experimental of pretest, posttest and control group design was adopted in this study. A sample of one hundred and sixty-four (164) Senior Secondary Two (SS2) students were selected from a population of twelve thousand, eight hundred and seventy-three (12,873) SS2 Students in Taraba State. Two schools with equivalent mean scores in the pre-test were randomly assigned to experimental and control groups. The experimental group students were stratified according to ability levels of low, medium and high. The experimental group was guided by the research assistants using the cooperative learning instructional package. After six weeks post-test was administered to the two groups while the retention test was administered two weeks after the post-test. The researcher developed a 50-item Mathematics Achievement Test (MAT) which was validated by experts obtaining the reliability coefficient of 0.87. Mean scores and standard deviations were used to answer the research questions while the Analysis of Co-variance (ANCOVA) was used to test the hypotheses. Major findings from the statistical analysis showed that cooperative learning strategy has a significant effect on the mean achievement of students as well as retention among students of high, medium and low ability in mathematics. However, cooperative learning strategy has no effect on the interaction of ability level and retention. Based on the results obtained, it was therefore recommended that the adoption of the use of cooperative learning strategy in the teaching and learning of mathematics in senior secondary schools be initiated, maintained and sustained for the benefit of senior secondary school students in Taraba State. Periodic Government sponsored in-service training in form of long vacation training programme, workshops, conferences and seminars on the nature, scope, and use of cooperative learning strategy should be organized for senior secondary school mathematics teachers in Taraba state.

Keywords: ability level, cooperative learning, mathematics achievement, retention

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8686 Testing the Weak Form Efficiency of Islamic Stock Market: Empirical Evidence from Indonesia

Authors: Herjuno Bagus Wicaksono, Emma Almira Fauni, Salma Amelia Dina

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The Efficient Market Hypothesis (EMH) states that, in an efficient capital market, price fully reflects the information available in the market. This theory has influenced many investors behavior in trading in the stock market. Advanced researches have been conducted to test the efficiency of the stock market in particular countries. Indonesia, as one of the emerging countries, has performed substantial growth in the past years. Hence, this paper aims to examine the efficiency of Islamic stock market in Indonesia in its weak form. The daily stock price data from Indonesia Sharia Stock Index (ISSI) for the period October 2015 to October 2016 were used to do the statistical tests: Run Test and Serial Correlation Test. The results show that there is no serial correlation between the current price with the past prices and the market follows the random walk. This research concludes that Indonesia Islamic stock market is weak form efficient.

Keywords: efficient market hypothesis, Indonesia sharia stock index, random walk, weak form efficiency

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8685 Performance of the Abbott RealTime High Risk HPV Assay with SurePath Liquid Based Cytology Specimens from Women with Low Grade Cytological Abnormalities

Authors: Alexandra Sargent, Sarah Ferris, Ioannis Theofanous

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The Abbott RealTime High Risk HPV test (RealTime HPV) is one of five assays clinically validated and approved by the English NHS Cervical Screening Programme (CSP) for HPV triage of low grade dyskaryosis and test-of-cure of treated Cervical Intraepithelial Neoplasia. The assay is a highly automated multiplex real-time PCR test for detecting 14 high risk (hr) HPV types, with simultaneous differentiation of HPV 16 and HPV 18 versus non-HPV 16/18 hrHPV. An endogenous internal control ensures sample cellularity, controls extraction efficiency and PCR inhibition. The original cervical specimen collected in SurePath (SP) liquid-based cytology (LBC) medium (BD Diagnostics) and the SP post-gradient cell pellets (SPG) after cytological processing are both CE marked for testing with the RealTime HPV test. During the 2011 NHSCSP validation of new tests only the original aliquot of SP LBC medium was investigated. Residual sample volume left after cytology slide preparation is low and may not always have sufficient volume for repeat HPV testing or for testing of other biomarkers that may be implemented in testing algorithms in the future. The SPG samples, however, have sufficient volumes to carry out additional testing and necessary laboratory validation procedures. This study investigates the correlation of RealTime HPV results of cervical specimens collected in SP LBC medium from women with low grade cytological abnormalities observed with matched pairs of original SP LBC medium and SP post-gradient cell pellets (SPG) after cytology processing. Matched pairs of SP and SPG samples from 750 women with borderline (N = 392) and mild (N = 351) cytology were available for this study. Both specimen types were processed and parallel tested for the presence of hrHPV with RealTime HPV according to the manufacturer´s instructions. HrHPV detection rates and concordance between test results from matched SP and SPGCP pairs were calculated. A total of 743 matched pairs with valid test results on both sample types were available for analysis. An overall-agreement of hrHPV test results of 97.5% (k: 0.95) was found with matched SP/SPG pairs and slightly lower concordance (96.9%; k: 0.94) was observed on 392 pairs from women with borderline cytology compared to 351 pairs from women with mild cytology (98.0%; k: 0.95). Partial typing results were highly concordant in matched SP/SPG pairs for HPV 16 (99.1%), HPV 18 (99.7%) and non-HPV16/18 hrHPV (97.0%), respectively. 19 matched pairs were found with discrepant results: 9 from women with borderline cytology and 4 from women with mild cytology were negative on SPG and positive on SP; 3 from women with borderline cytology and 3 from women with mild cytology were negative on SP and positive on SPG. Excellent correlation of hrHPV DNA test results was found between matched pairs of SP original fluid and post-gradient cell pellets from women with low grade cytological abnormalities tested with the Abbott RealTime High-Risk HPV assay, demonstrating robust performance of the test with both specimen types and reassuring the utility of the assay for cytology triage with both specimen types.

Keywords: Abbott realtime test, HPV, SurePath liquid based cytology, surepath post-gradient cell pellet

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8684 Innovative Teaching Learning Techniques and Learning Difficulties of Adult Learners in Literacy Education Programmes in Calabar Metropolis, Cross River State, Nigeria

Authors: Simon Ibor Akpama

Abstract:

The study investigated the extent to which innovative teaching-learning techniques can influence and attenuate learning difficulties among adult learners participating in different literacy education programmes in Calabar Metropolis, Cross River State, Nigeria. A quasi-experimental design was adopted to collect data from a sample size of 150 participants of the programme. The sample was drawn using the simple random sampling method. As an experimental study, the 150 participants were divided into two equal groups –the first was the experimental group while the second was the control. A pre-test was administered to the two groups which were later exposed to a post-test after treatment. Two instruments were used for data collection. The first was the guide for the Literacy Learning Difficulties Inventory (LLDI). Three hypotheses were postulated and tested as .05 level of significance using Analysis of Covariance (ANOVA) test statistics. Results of the analysis firstly showed that the two groups (treatment and control) did not differ in the pre-test regarding their literacy learning difficulties. Secondly, the result showed that for each hypothesis, innovative teaching-learning techniques significantly influenced adult learners’ (participants) literacy learning difficulties. Based on these findings, the study recommends the use of innovative teaching-learning techniques in adult literacy education centres to mitigate the learning difficulties of adult learners in literacy education programmes in Calabar Metropolis.

Keywords: teaching, learning, techniques, innovative, difficulties, programme

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8683 A Machine Learning Approach for Classification of Directional Valve Leakage in the Hydraulic Final Test

Authors: Christian Neunzig, Simon Fahle, Jürgen Schulz, Matthias Möller, Bernd Kuhlenkötter

Abstract:

Due to increasing cost pressure in global markets, artificial intelligence is becoming a technology that is decisive for competition. Predictive quality enables machinery and plant manufacturers to ensure product quality by using data-driven forecasts via machine learning models as a decision-making basis for test results. The use of cross-process Bosch production data along the value chain of hydraulic valves is a promising approach to classifying the quality characteristics of workpieces.

Keywords: predictive quality, hydraulics, machine learning, classification, supervised learning

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8682 Simo-syl: A Computer-Based Tool to Identify Language Fragilities in Italian Pre-Schoolers

Authors: Marinella Majorano, Rachele Ferrari, Tamara Bastianello

Abstract:

The recent technological advance allows for applying innovative and multimedia screen-based assessment tools to test children's language and early literacy skills, monitor their growth over the preschool years, and test their readiness for primary school. Several are the advantages that a computer-based assessment tool offers with respect to paper-based tools. Firstly, computer-based tools which provide the use of games, videos, and audio may be more motivating and engaging for children, especially for those with language difficulties. Secondly, computer-based assessments are generally less time-consuming than traditional paper-based assessments: this makes them less demanding for children and provides clinicians and researchers, but also teachers, with the opportunity to test children multiple times over the same school year and, thus, to monitor their language growth more systematically. Finally, while paper-based tools require offline coding, computer-based tools sometimes allow obtaining automatically calculated scores, thus producing less subjective evaluations of the assessed skills and provide immediate feedback. Nonetheless, using computer-based assessment tools to test meta-phonological and language skills in children is not yet common practice in Italy. The present contribution aims to estimate the internal consistency of a computer-based assessment (i.e., the Simo-syl assessment). Sixty-three Italian pre-schoolers aged between 4;10 and 5;9 years were tested at the beginning of the last year of the preschool through paper-based standardised tools in their lexical (Peabody Picture Vocabulary Test), morpho-syntactical (Grammar Repetition Test for Children), meta-phonological (Meta-Phonological skills Evaluation test), and phono-articulatory skills (non-word repetition). The same children were tested through Simo-syl assessment on their phonological and meta-phonological skills (e.g., recognise syllables and vowels and read syllables and words). The internal consistency of the computer-based tool was acceptable (Cronbach's alpha = .799). Children's scores obtained in the paper-based assessment and scores obtained in each task of the computer-based assessment were correlated. Significant and positive correlations emerged between all the tasks of the computer-based assessment and the scores obtained in the CMF (r = .287 - .311, p < .05) and in the correct sentences in the RCGB (r = .360 - .481, p < .01); non-word repetition standardised test significantly correlates with the reading tasks only (r = .329 - .350, p < .05). Further tasks should be included in the current version of Simo-syl to have a comprehensive and multi-dimensional approach when assessing children. However, such a tool represents a good chance for the teachers to early identifying language-related problems even in the school environment.

Keywords: assessment, computer-based, early identification, language-related skills

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8681 The Role of Creative Thinking in Science Education

Authors: Jindriska Svobodova, Jan Novotny

Abstract:

A teacher’s attitude to creativity plays an essential role in the thinking development of his/her students. The purpose of this study is to understand if a science teacher's personal creativity can modify his/her ability to produce various kinds of questions. This research used an education activity based on cosmic sketches and pictures by K.E. Tsiolkovsky, the founder of astronautics, to explore if any relationship between individual creativity and the asking questions skill exists. As a screening instrument, which allows an assessment of the respondent's creative potential, a common test of creative thinking was used. The results of the creativity test and the diversity of the questions are mentioned.

Keywords: science education, active learning, physics teaching, religious cosmology

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8680 Travel Planning in Public Transport Networks Applying the Algorithm A* for Metropolitan District of Quito

Authors: M. Fernanda Salgado, Alfonso Tierra, Wilbert Aguilar

Abstract:

The present project consists in applying the informed search algorithm A star (A*) to solve traveler problems, applying it by urban public transportation routes. The digitization of the information allowed to identify 26% of the total of routes that are registered within the Metropolitan District of Quito. For the validation of this information, data were taken in field on the travel times and the difference with respect to the times estimated by the program, resulting in that the difference between them was not greater than 2:20 minutes. We validate A* algorithm with the Dijkstra algorithm, comparing nodes vectors based on the public transport stops, the validation was established through the student t-test hypothesis. Then we verified that the times estimated by the program using the A* algorithm are similar to those registered on field. Furthermore, we review the performance of the algorithm generating iterations in both algorithms. Finally, with these iterations, a hypothesis test was carried out again with student t-test where it was concluded that the iterations of the base algorithm Dijsktra are greater than those generated by the algorithm A*.

Keywords: algorithm A*, graph, mobility, public transport, travel planning, routes

Procedia PDF Downloads 241
8679 Assessment of Hamstring, Lower Back and Upper Body Flexibility in War Disabled Individuals in Sri Lanka North and East Region

Authors: Esther Liyanage, Indrajith Liyanage, A. A. J. Rajaratne

Abstract:

During the 30 year civil war in Sri Lanka, a large number of individuals were injured and disabled. These disabilities have reduced their daily physical activities which may cause reduction in flexibility of upper limb, shoulder girdle, lower back and lower limb. Muscle flexibility is important for a healthy lifestyle. The main objective of the study was to assess the upper limb, shoulder girdle and lower back, hamstring flexibility of the intact lower limb in disabled individuals in the North and Eastern parts of Sri Lanka. Back saver sits and reach test and shoulder scratch test described in FITNESS GRAM was used in the study. A total of 125 disabled soldiers with lower limb disabilities were recruited for the study. Flexibility of the lower back and hamstring muscles of uninjured lower limb was measured using back saver sit and reach test described by Wells and Dillon (1952). Upper limb and shoulder girdle flexibility was assessed using shoulder stretch test. Score 0-3 was given according to the ability to reach Superior medial angle of the opposite scapula, top of the head or the mouth. The results indicate that 31 (24.8%) disabled soldiers have lower limb flexibility less than 8, 2 (1.6 % ) have flexibility of 8, 2 (1.6 %) have flexibility of 8.5, 11 ( 8.8% ) have flexibility of 9, 14 (11.2 %) have flexibility of 9.5, 23 (18.4 %) have flexibility of 10, 17 (13.6 %) have 10.5 flexibility, 13 (10.4%) have 11 flexibility, 2 (1.6%) have 11.5 flexibility, 10 (8 %) have flexibility of 12 and 3 (2.34 %) have flexibility of 12.5. Six disabled soldiers (4.8%) have upper limb flexibility of 2 and remaining 95.2% have normal upper limb flexibility (score 3). A reduction in the flexibility of muscles in lower body and lower limbs was seen in 25% disabled soldiers which could be due to reduction in their daily physical activities.

Keywords: disability, flexibility, rehabilitation, quality of life

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8678 Prevalence and Spatial Distribution of Anaemia in Ethiopia using 2011 EDHS

Authors: Bedilu A. Ejigu, Eshetu Wencheko, Kiros Berhane

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Anaemia is a condition in which the haemoglobin concentration falls below an established cut-off value due to a decrease in the number and size of red blood cells. The current study aimed to assess the spatial pattern and identify predictors related to anaemia using the third Ethiopian demographic health survey which was conducted in 2010. To achieve this objective, this study took into account the clustered nature of the data. As a result, multilevel modeling has been used in the statistical analysis. For analysis purpose, only complete cases from 15,909 females, and 13,903 males were considered. Among all subjects who agreed for haemoglobin test, 5.49 %males, and 19.86% females were anaemic. In both binary and ordinal outcome modeling approaches, educational level, age, wealth index, BMI and HIV status were identified to be significant predictors for anaemia prevalence. Furthermore, it was noted that pregnant women were more anaemic than non-pregnant women. As revealed by Moran's I test, significant spatial autocorrelation was noted across clusters. The risk of anaemia was found to vary across different regions, and higher prevalence was observed in Somali and Affar region.

Keywords: anaemia, Moran's I test, multilevel models, spatial pattern

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8677 Formulation and Characterization of Active Edible Films from Cassava Starch for Snacks and Savories

Authors: P. Raajeswari, S. M. Devatha, S. Yuvajanani, U. Rashika

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Edible food packaging are the need of the hour to save life on land and under water by eliminating waste cycle and replacing Single Use Plastics at grass root level as it can be eaten or composted as such. Cassava (Manihot esculenta) selected for making edible films are rich source of starch, and also it exhibit good sheeting propertiesdue to the high amylose: amylopectin content. Cassava starch was extracted by manual method at a laboratory scale and yielded 65 per cent. Edible films were developed by adding food grade plasticizers and water. Glycerol showed good plasticizing property as compared to sorbitol and polylactic acid in both manual (petri dish) and machine (film making machine) production. The thickness of the film is 0.25±0.03 mm. Essential oil and components from peels like pomegranate, orange, pumpkin, onion, and banana brat, and herbs like tulsi and country borage was extracted through the standardized aqueous and alkaline method. In the standardized film, the essential oil and components from selected peel and herbs were added to the casting solution separately and casted the film. It was added to improve the anti-oxidant, anti-microbial and optical properties. By inclusion of extracts, it reduced the bubble formation while casting. FTIR, Water Vapor and Oxygen Transmission Rate (WVTR and OTR), tensile strength, microbial load, shelf life, and degradability of the films were done to analyse the mechanical property of the standardized films. FTIR showed the presence of essential oil. WVTR and OTR of the film was improved after inclusion of essential oil and extracts from 1.312 to 0.811 cm₃/m₂ and 15.12 to 17.81 g/ m₂.d. Inclusion of essential oil from herbs showed better WVTR and OTR than the inclusion of peel extract and standard. Tensile strength and Elongation at break has not changed by essential oil and extracts at 0.86 ± 0.12 mpa and 14 ± 2 at 85 N force. By inclusion of extracts, an optical property of the film enhanced, and it increases the appearance of the packaging material. The films were completely degraded on 84thdays and partially soluble in water. Inclusion of essential oil does not have impact on degradability and solubility. The microbial loads of the active films were decreased from 15 cfu/gm to 7 cfu/gm. The films can be stored at frozen state for 24 days and 48 days at atmospheric temperature when packed with South Indian snacks and savories.

Keywords: active films, cassava starch, plasticizer, characterization

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8676 Improvement of Mechanical Properties of Recycled High-Density and Low-Density Polyethylene Blends through Extrusion, Reinforcement, and Compatibilization Approaches

Authors: H. Kharmoudi, S. Elkoun, M. Robert, C. Diez

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In the literature, the elaboration of polymer blends based on recycled HDPE and LDPE is challenging because of the non-miscibility. Ensuring the compatibility of blends is one of the challenges; this study will discuss the different methods to be adopted to assess the compatibility of polymer blends. The first one aims to act on the extrusion process while varying the speed, flow rate, and residence time. The second method has as its purpose the use of grafted anhydride maleic elastomer chains as a compatibilizer. The results of the formulations will be characterized by means of differential scanning calorimetric (DSC) as well as mechanical tensile and bending tests to assess whether pipes made from recycled polyethylene meet the standards.

Keywords: recycled HDPE, LDPE, compatibilizer, mechanical tests

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8675 Influence of Controlled Retting on the Quality of the Hemp Fibres Harvested at the Seed Maturity by Using a Designed Lab-Scale Pilot Unit

Authors: Brahim Mazian, Anne Bergeret, Jean-Charles Benezet, Sandrine Bayle, Luc Malhautier

Abstract:

Hemp fibers are increasingly used as reinforcements in polymer matrix composites due to their competitive performance (low density, mechanical properties and biodegradability) compared to conventional fibres such as glass fibers. However, the huge variation of their biochemical, physical and mechanical properties limits the use of these natural fibres in structural applications when high consistency and homogeneity are required. In the hemp industry, traditional processes termed field retting are commonly used to facilitate the extraction and separation of stem fibers. This retting treatment consists to spread out the stems on the ground for a duration ranging from a few days to several weeks. Microorganisms (fungi and bacteria) grow on the stem surface and produce enzymes that degrade pectinolytic substances in the middle lamellae surrounding the fibers. This operation depends on the weather conditions and is currently carried out very empirically in the fields so that a large variability in the hemp fibers quality (mechanical properties, color, morphology, chemical composition…) is resulting. Nonetheless, if controlled, retting might be favorable for good properties of hemp fibers and then of hemp fibers reinforced composites. Therefore, the present study aims to investigate the influence of controlled retting within a designed environmental chamber (lab-scale pilot unit) on the quality of the hemp fibres harvested at the seed maturity growth stage. Various assessments were applied directly on fibers: color observations, morphological (optical microscope), surface (ESEM), biochemical (gravimetry) analysis, spectrocolorimetric measurements (pectins content), thermogravimetric analysis (TGA) and tensile testing. The results reveal that controlled retting leads to a rapid change of color from yellow to dark grey due to development of microbial communities (fungi and bacteria) at the stem surface. An increase of thermal stability of fibres due to the removal of non-cellulosic components along retting is also observed. A separation of bast fibers to elementary fibers occurred with an evolution of chemical composition (degradation of pectins) and a rapid decrease in tensile properties (380MPa to 170MPa after 3 weeks) due to accelerated retting process. The influence of controlled retting on the biocomposite material (PP / hemp fibers) properties is under investigation.

Keywords: controlled retting, hemp fibre, mechanical properties, thermal stability

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8674 Treatments for Overcoming Dormancy of Leucaena Seeds (Leucaena leucocephala)

Authors: Tiago Valente, Erico Lima, Bruno Deminicis, Andreia Cezario, Wallacy Santos, Fabiane Brito

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Introduction: The Leucaena leucocephala known as leucaena is a perennial legume shrub of subtropical regions in which the forage shows favorable characteristics for livestock production. The objective of the study was to evaluate the influence of methods for overcoming dormancy the seeds of Leucaena leucocephala (Lam.). Materials and Methods: The number of germinated seeds was evaluated daily at the germination criterion radicle protrusion (growth, with about 2 cm long, the emerged seedlings of all). After the counting of the number of germinated seeds daily, the following characteristics were evaluated: Step 1: Germination count which represents the cumulative percentage of germinated seeds on the third day after the start of the test (Germ3); Step 2: Percentage of germinated seeds that correspond to the total percentage of seeds that germinate until the a seventh day after start of the test (Germ7); Step 3: Percentage of germinated seeds that correspond to the total percentage of seeds that germinate until the fifteenth day after start of the test (Germ15);Step 4: Germination speed index (GSI), which was calculated with number of germinated seeds to the nth observation; divided by number of days after sowing. Step 5: Total count of seeds do not germinate after 15 days (NGerm).The seed treatments were: (T1) water at 100 ºC/10 min; (T2) water at 100 ºC/1 min; (T3) Acetone (10 min); (T4) Ethyl alcohol (10 minutes); and (T5) intact seeds (control). Data were analyzed using a completely randomized design with eight replications, and it was adopted the Tukey test at 5% significance level. Results and Discussion: The treatment T1, had the highest speed of germination of seeds GSI, differed (P < 0.05). The T5 treatment (control) was the slowest response, between treatments until the seventh day after the beginning of the test (Germ7), with an amount of 20% accumulation of germinated seeds. The worst result of germination it was T5, with 30% of non-germinated seeds after 15 days of sowing. Acknowledgments: IFGoiano and CNPq (Brazil).

Keywords: acetone, boiling water, germination, seed physiology

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8673 Reliability of Movement Assessment Battery for Children-2 Age Band 3 Using Multiple Testers

Authors: Jernice S. Y. Tan

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Introduction: Reliability within and between testers is vital to ensure the accuracy of any motor assessment instrument. However, reliability checks of the Movement Assessment Battery for Children-2 (MABC-2) age band 3 using multiple testers assigned to different MABC-2 tasks for the same group of participants are uncommon. Multiple testers were not stated as a choice in the MABC-2 manual. Therefore, the purpose of this study was to determine the inter- and intra-tester reliability for using multiple testers to administer the test protocols of MABC-2 age band 3. Methods: Thirty volunteered adolescents (n = 30; 15 males, 15 females; age range: 13 – 16 years) performed the eight tasks in a randomised sequence at three different test stations for the MABC-2 task components (Manual Dexterity, Aiming and Catching, Balance). Ethics approval and parental consent were obtained. The participants were videotaped while performing the test protocols of MABC-2 age band 3. Five testers were involved in the data collection process. They were Sports Science graduating students doing their final year project and were supervised by experienced motor assessor. Inter- and intra-tester reliability checks using intra-class coefficient (ICC) were carried out using the videotaped data. Results: The inter-tester reliability between the five testers for the eight tasks ranged from rᵢcc = 0.705 to rᵢcc = 0.995. This suggests that the average agreement between them was considered good to excellent. With the exception of one tester who had rᵢcc = 0.687 for one of the eight tasks (i.e. zip-zap hopping), the intra-tester reliability within each tester ranged from rᵢcc = 0.728 to rᵢcc = 1.000, and this also suggested good to excellent consistency within testers. Discussion: The use of multiple testers with good intra-tester reliability for different test stations is feasible. This method allows several participants to be assessed concurrently at different test stations and saves overall data collection time. Therefore, it is recommended that the administering of MABC-2 with multiple testers should be extended to other age bands ensuring the feasibility of such method for other age bands.

Keywords: adolescents, MABC, motor assessment, motor skills, reliability

Procedia PDF Downloads 324