Search results for: test methods.
6206 Advancing the Theory of Planned Behavior within Dietary and Physical Domains among Type 2 Diabetics: A Mixed Methods Approach
Authors: D.O. Omondi, M.K. Walingo, G.M. Mbagaya, L.O.A. Othuon
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Many studies have applied the Theory of Planned Behavior (TPB) in predicting health behaviors among unique populations. However, a new paradigm is emerging where focus is now directed to modification and expansion of the TPB model rather than utilization of the traditional theory. This review proposes new models modified from the Theory of Planned Behavior and suggest an appropriate study design that can be used to test the models within physical activity and dietary practice domains among Type 2 diabetics in Kenya. The review was conducted by means of literature search in the field of nutrition behavior, health psychology and mixed methods using predetermined key words. The results identify pre-intention and post intention gaps within the TPB model that need to be filled. Additional psychosocial factors are proposed to be included in the TPB model to generate new models and the efficacy of these models tested using mixed methods design.Keywords: Physical activity, diet, Type 2 diabetes, behaviorchange theory, model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26976205 Detecting the Nonlinearity in Time Series from Continuous Dynamic Systems Based on Delay Vector Variance Method
Authors: Shumin Hou, Yourong Li, Sanxing Zhao
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Much time series data is generally from continuous dynamic system. Firstly, this paper studies the detection of the nonlinearity of time series from continuous dynamics systems by applying the Phase-randomized surrogate algorithm. Then, the Delay Vector Variance (DVV) method is introduced into nonlinearity test. The results show that under the different sampling conditions, the opposite detection of nonlinearity is obtained via using traditional test statistics methods, which include the third-order autocovariance and the asymmetry due to time reversal. Whereas the DVV method can perform well on determining nonlinear of Lorenz signal. It indicates that the proposed method can describe the continuous dynamics signal effectively.
Keywords: Nonlinearity, Time series, continuous dynamics system, DVV method
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16176204 Artificial Accelerated Ageing Test of Silicone Rubber Housing Material for Lightning Arrester
Authors: W. Payakcho, J. Grasaesom, S. Thong-om, B. Marungsri
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This paper presents the experimental results of silicone rubber housing material for 24kV lightning arrester under artificial accelerated ageing test based on IEC 61109 specifications. Specimens having inclined and alternated shed made of HTV silicone rubber with ATH content and having leakage distance 625 mm were tested continuously 1000 hrs in artificial salt fog chamber. After 1000 hrs of salt fog ageing test, obviously surface erosion was observed on trunk between the upper large shed and the lower small shed near the energized end. Decreasing in hydrophobicity and increasing in hardness were measured on tested specimen comparing with new specimen. Chemical analysis by ATR-FTIR confirmed the observation results.
Keywords: Accelerated ageing test, Silicone rubber housing material, salt fog test, Lightning Arrester, Ageing
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29426203 Automatic Verification Technology of Virtual Machine Software Patch on IaaS Cloud
Authors: Yoji Yamato
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In this paper, we propose an automatic verification technology of software patches for user virtual environments on IaaS Cloud to decrease verification costs of patches. In these days, IaaS services have been spread and many users can customize virtual machines on IaaS Cloud like their own private servers. Regarding to software patches of OS or middleware installed on virtual machines, users need to adopt and verify these patches by themselves. This task increases operation costs of users. Our proposed method replicates user virtual environments, extracts verification test cases for user virtual environments from test case DB, distributes patches to virtual machines on replicated environments and conducts those test cases automatically on replicated environments. We have implemented the proposed method on OpenStack using Jenkins and confirmed the feasibility. Using the implementation, we confirmed the effectiveness of test case creation efforts by our proposed idea of 2-tier abstraction of software functions and test cases. We also evaluated the automatic verification performance of environment replications, test cases extractions and test cases conductions.
Keywords: OpenStack, Cloud Computing, Automatic verification, Jenkins.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21606202 Analysis of Physicochemical Properties on Prediction of R5, X4 and R5X4 HIV-1 Coreceptor Usage
Authors: Kai-Ti Hsu, Hui-Ling Huang, Chun-Wei Tung, Yi-Hsiung Chen, Shinn-Ying Ho
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Bioinformatics methods for predicting the T cell coreceptor usage from the array of membrane protein of HIV-1 are investigated. In this study, we aim to propose an effective prediction method for dealing with the three-class classification problem of CXCR4 (X4), CCR5 (R5) and CCR5/CXCR4 (R5X4). We made efforts in investigating the coreceptor prediction problem as follows: 1) proposing a feature set of informative physicochemical properties which is cooperated with SVM to achieve high prediction test accuracy of 81.48%, compared with the existing method with accuracy of 70.00%; 2) establishing a large up-to-date data set by increasing the size from 159 to 1225 sequences to verify the proposed prediction method where the mean test accuracy is 88.59%, and 3) analyzing the set of 14 informative physicochemical properties to further understand the characteristics of HIV-1coreceptors.Keywords: Coreceptor, genetic algorithm, HIV-1, SVM, physicochemical properties, prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23736201 Biaxial Testing of Fabrics - A Comparison of Various Testing Methodologies
Authors: O.B. Ozipek, E. Bozdag, E. Sunbuloglu, A. Abdullahoglu, E. Belen, E. Celikkanat
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In textile industry, besides the conventional textile products, technical textile goods, that have been brought external functional properties into, are being developed for technical textile industry. Especially these products produced with weaving technology are widely preferred in areas such as sports, geology, medical, automotive, construction and marine sectors. These textile products are exposed to various stresses and large deformations under typical conditions of use. At this point, sufficient and reliable data could not be obtained with uniaxial tensile tests for determination of the mechanical properties of such products due to mainly biaxial stress state. Therefore, the most preferred method is a biaxial tensile test method and analysis. These tests and analysis is applied to fabrics with different functional features in order to establish the textile material with several characteristics and mechanical properties of the product. Planar biaxial tensile test, cylindrical inflation and bulge tests are generally required to apply for textile products that are used in automotive, sailing and sports areas and construction industry to minimize accidents as long as their service life. Airbags, seat belts and car tires in the automotive sector are also subject to the same biaxial stress states, and can be characterized by same types of experiments. In this study, in accordance with the research literature related to the various biaxial test methods are compared. Results with discussions are elaborated mainly focusing on the design of a biaxial test apparatus to obtain applicable experimental data for developing a finite element model. Sample experimental results on a prototype system are expressed.Keywords: Biaxial Stress, Bulge Test, Cylindrical Inflation, Fabric Testing, Planar Tension.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41356200 Sensitivity Comparison between Rapid Immuno-Chromatographic Device Test and ELISA in Detection and Sero-Prevalence of HBsAg and Anti-HCV antibodies in Apparently Healthy Blood Donors of Lahore, Pakistan
Authors: Natasha Hussain, Maleeha Aslam, Robina Farooq
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Hepatitis B and hepatitis C are among the most significant hepatic infections all around the world that may lead to hepatocellular carcinoma. This study is first time performed at the blood transfussion centre of Omar hospital, Lahore. It aims to determine the sero-prevalence of these diseases by screening the apparently healthy blood donors who might be the carriers of HBV or HCV and pose a high risk in the transmission. It also aims the comparison between the sensitivity of two diagnostic tests; chromatographic immunoassay – one step test device and Enzyme Linked Immuno Sorbant Assay (ELISA). Blood serum of 855 apparently healthy blood donors was screened for Hepatitis B surface antigen (HBsAg) and for anti HCV antibodies. SPSS version 12.0 and X2 (Chi-square) test were used for statistical analysis. The seroprevalence of HCV was 8.07% by the device method and by ELISA 9.12% and that of HBV was 5.6% by the device and 6.43% by ELISA. The unavailability of vaccination against HCV makes it more prevalent. Comparing the two diagnostic methods, ELISA proved to be more sensitive.Keywords: ELISA, Sensitivity comparison of diagnostic tests, seroprevalence of Hepatitis B and C
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21816199 Behavioral Studies on Multi-Directionally Reinforced 4-D Orthogonal Composites on Various Preform Configurations
Authors: Sriram Venkatesh, V. Murali Mohan, T. V. Karthikeyan
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The main advantage of multidirectionally reinforced composites is the freedom to orient selected fiber types and hence derives the benefits of varying fibre volume fractions and there by accommodate the design loads of the final structure of composites. This technology provides the means to produce tailored composites with desired properties. Due to the high level of fibre integrity with through thickness reinforcement those composites are expected to exhibit superior load bearing characteristics with capability to carry load even after noticeable and apparent fracture. However, a survey of published literature indicates inadequacy in the design and test data base for the complete characterization of the multidirectional composites. In this paper the research objective is focused on the development and testing of 4-D orthogonal composites with different preform configurations and resin systems. A preform is the skeleton 4D reinforced composite other than the matrix. In 4-D performs fibre bundles are oriented in three directions at 1200 with respect to each other and they are on orthogonal plane with the fibre in 4th direction. This paper addresses the various types of 4-D composite manufacturing processes and the mechanical test methods followed for the material characterization. A composite analysis is also made, experiments on course and fine woven preforms are conducted and the findings of test results are discussed in this paper. The interpretations of the test results reveal several useful and interesting features. This should pave the way for more widespread use of the perform configurations for allied applications.
Keywords: Multidirectionally Reinforced Composites, 4-D Orthogonal Preform, Course weave, Fine weave.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14046198 Study on the Impact of Size and Position of the Shear Field in Determining the Shear Modulus of Glulam Beam Using Photogrammetry Approach
Authors: Niaz Gharavi, Hexin Zhang
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The shear modulus of a timber beam can be determined using torsion test or shear field test method. The shear field test method is based on shear distortion measurement of the beam at the zone with the constant transverse load in the standardized four-point bending test. The current code of practice advises using two metallic arms act as an instrument to measure the diagonal displacement of the constructing square. The size and the position of the constructing square might influence the shear modulus determination. This study aimed to investigate the size and the position effect of the square in the shear field test method. A binocular stereo vision system has been employed to determine the 3D displacement of a grid of target points. Six glue laminated beams were produced and tested. Analysis of Variance (ANOVA) was performed on the acquired data to evaluate the significance of the size effect and the position effect of the square. The results have shown that the size of the square has a noticeable influence on the value of shear modulus, while, the position of the square within the area with the constant shear force does not affect the measured mean shear modulus.Keywords: Shear field test method, structural-sized test, shear modulus of Glulam beam, photogrammetry approach.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9916197 iDENTM Phones Automated Stress Testing
Authors: Wei Hoo Chong
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System testing is actually done to the entire system against the Functional Requirement Specification and/or the System Requirement Specification. Moreover, it is an investigatory testing phase, where the focus is to have almost a destructive attitude and test not only the design, but also the behavior and even the believed expectations of the customer. It is also intended to test up to and beyond the bounds defined in the software/hardware requirements specifications. In Motorola®, Automated Testing is one of the testing methodologies uses by GSG-iSGT (Global Software Group - iDEN TM Subcriber Group-Test) to increase the testing volume, productivity and reduce test cycle-time in iDEN TM phones testing. Testing is able to produce more robust products before release to the market. In this paper, iHopper is proposed as a tool to perform stress test on iDEN TM phonse. We will discuss the value that automation has brought to iDEN TM Phone testing such as improving software quality in the iDEN TM phone together with some metrics. We will also look into the advantages of the proposed system and some discussion of the future work as well.Keywords: Testing, automated testing, stress testing, software quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14776196 Biofungicide Trichodex WP
Authors: Snezana Rajkovic, Miroslava Markovic, Radoslav Rajkovic, Ljubinko Rakonjac
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Grey mold on grape is caused by the fungus Botrytis cinerea Pers. Trichodex WP, a new biofungicide, that contains fungal spores of Trichoderma harzianum Rifai, was used for biological control of Grey mold on grape. The efficacy of Trichodex WP has been reported from many experiments. Experiments were carried out in the locality – Banatski Karlovac, on grapevine species – talijanski rizling. The trials were set according to instructions of methods PP1/152(2) and PP1/17(3) , according to a fully randomized block design. Phytotoxicity was estimated by PP methods 1/135(2), the intensity of infection according to Towsend Heuberger , the efficiency by Abbott, the analysis of variance with Duncan test and PP/181(2). Application of Trichodex WP is limited to the first two treatments. Other treatments are performed with the fungicides based on a.i. procymidone, vinclozoline and iprodione.Keywords: Biofungicides, efficacy, grey mold, Trichodex WP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41566195 Simulation Based Performance Comparison of Different Control Methods of ZSI Feeding Industrial Drives
Authors: Parag Nihawan, Ravinder Singh Bhatia, Dinesh Kumar Jain
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Industrial drives are source of serious power quality problems. In this, two typical industrial drives have been dealt with, namely, FOC induction motor drives and DTC induction motor drive. The Z-source inverter is an emerging topology of power electronic converters which is capable of buck boost characteristics. The performances of different control methods based Z-source inverters feeding these industrial drives have been investigated, in this work. The test systems have been modeled and simulated in MATLAB/SIMULINK. The results obtained after carrying out these simulations have been used to draw the conclusions.
Keywords: Z-Source Inverter, total harmonic distortion, direct torque control, field orientation control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10266194 Development of a Biomechanical Method for Ergonomic Evaluation: Comparison with Observational Methods
Authors: M. Zare, S. Biau, M. Croq, Y. Roquelaure
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A wide variety of observational methods have been developed to evaluate the ergonomic workloads in manufacturing. However, the precision and accuracy of these methods remain a subject of debate. The aims of this study were to develop biomechanical methods to evaluate ergonomic workloads and to compare them with observational methods.
Two observational methods, i.e. SCANIA Ergonomic Standard (SES) and Rapid Upper Limb Assessment (RULA), were used to assess ergonomic workloads at two simulated workstations. They included four tasks such as tightening & loosening, attachment of tubes and strapping as well as other actions. Sensors were also used to measure biomechanical data (Inclinometers, Accelerometers, and Goniometers).
Our findings showed that in assessment of some risk factors both RULA & SES were in agreement with the results of biomechanical methods. However, there was disagreement on neck and wrist postures. In conclusion, the biomechanical approach was more precise than observational methods, but some risk factors evaluated with observational methods were not measurable with the biomechanical techniques developed.
Keywords: Ergonomic, Observational Method, Biomechanical method, Workload.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 50796193 Using Scanning Electron Microscope and Computed Tomography for Concrete Diagnostics of Airfield Pavements
Authors: M. Linek
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This article presents the comparison of selected evaluation methods regarding microstructure modification of hardened cement concrete intended for airfield pavements. Basic test results were presented for two pavement quality concrete lots. Analysis included standard concrete used for airfield pavements and modern material solutions based on concrete composite modification. In case of basic grain size distribution of concrete cement CEM I 42,5HSR NA, fine aggregate and coarse aggregate fractions in the form of granite chippings, water and admixtures were considered. In case of grain size distribution of modified concrete, the use of modern modifier as substitute of fine aggregate was suggested. Modification influence on internal concrete structure parameters using scanning electron microscope was defined. Obtained images were compared to the results obtained using computed tomography. Opportunity to use this type of equipment for internal concrete structure diagnostics and an attempt of its parameters evaluation was presented. Obtained test results enabled to reach a conclusion that both methods can be applied for pavement quality concrete diagnostics, with particular purpose of airfield pavements.Keywords: Scanning electron microscope, computed tomography, cement concrete, airfield pavements.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11046192 A New Correlation between SPT and CPT for Various Soils
Authors: Fauzi Jarushi, S. AlKaabim, Paul Cosentino
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The Standard Penetration Test (SPT) is the most common in situ test for soil investigations. On the other hand, the Cone Penetration Test (CPT) is considered one of the best investigation tools. Due to the fast and accurate results that can be obtained it complaints the SPT in many applications like field explorations, design parameters, and quality control assessments. Many soil index and engineering properties have been correlated to both of SPT and CPT. Various foundation design methods were developed based on the outcome of these tests. Therefore it is vital to correlate these tests to each other so that either one of the tests can be used in the absence of the other, especially for preliminary evaluation and design purposes. The primary purpose of this study was to investigate the relationships between the SPT and CPT for different type of sandy soils in Florida. Data for this research were collected from number of projects sponsored by the Florida Department of Transportation (FDOT), six sites served as the subject of SPT-CPT correlations. The correlations were established between the cone resistance (qc), sleeve friction (fs) and the uncorrected SPT blow counts (N) for various soils. A positive linear relationship was found between qc, fs and N for various sandy soils. In general, qc versus N showed higher correlation coefficients than fs versus N. qc/N ratios were developed for different soil types and compared to literature values, the results of this research revealed higher ratios than literature values.
Keywords: In situ tests, Correlation, SPT, CPT.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 165486191 Students´ Knowledge, or Random Choice in ESP?
Authors: Ivana Šimonová
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As widely accepted, didactic multiple-choice tests are referred as a tool providing feedback easily and quickly. Despite the final test scores are corrected by a special formula and number of high plausibility distractors is taken into consideration, the results may be influenced by the random choice. The survey was held in three academic years at the Faculty of Informatics and Management, University of Hradec Kralove, Czech Republic, where the multiple-choice test scores were compared to the open-answer ones. The research sample included 567 respondents. The collected data were processed by the NCSS2007 statistic software by the method of frequency and multiple regression analysis and presented in the form of figures and tables. The results proved statistically significant differences in test scores in academic years 2 and 3, and were discussed from the point of the credit system and conditions for teaching/learning English in the Czech education system.
Keywords: ESP, higher education, multiple-choice test, open-answer test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16166190 The Impact of Drama Education on Creativity Development at Preschool Children
Authors: Vladimíra Hornáčková
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This paper points out at the importance of creativity development in children of preschool age and analyses certain conditions and pedagogical principles which should be respected during the development of creativity in kindergartens. Research survey focuses on the development of creativity reflection at children in kindergartens at preschool age and based on a test of creativity it compares creativity of children in experimental and control groups. The goal is to find out if there are any differences among children in experimental and control classrooms in kindergartens; wherein experimental groups, there is preschool education with the use of drama education while in control groups there is not. On the basis of certain aspects, the gained data is compared through descriptive methods and correlations. Research results refer to reserves in creativity development in modern pre-primary education in the context of implemented and expected changes in didactic approach in the education of kindergartens.
Keywords: Preschool child, drama in education, research, test of creativity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18816189 Dialogue Meetings as an Arena for Collaboration and Reflection among Researchers and Practitioners
Authors: Kerstin Grunden, Ann Svensson, Berit Forsman, Christina Karlsson, Ayman Obeid
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The research question of the article is to explore whether the dialogue meetings method could be relevant for reflective learning among researchers and practitioners when welfare technology should be implemented in municipalities, or not. A testbed was planned to be implemented in a retirement home in a Swedish municipality, and the practitioners worked with a pre-study of that testbed. In the article, the dialogue between the researchers and the practitioners in the dialogue meetings is described and analyzed. The potential of dialogue meetings as an arena for learning and reflection among researchers and practitioners is discussed. The research methodology approach is participatory action research with mixed methods (dialogue meetings, focus groups, participant observations). The main findings from the dialogue meetings were that the researchers learned more about the use of traditional research methods, and the practitioners learned more about how they could improve their use of the methods to facilitate change processes in their organization. These findings have the potential both for the researchers and the practitioners to result in more relevant use of research methods in change processes in organizations. It is concluded that dialogue meetings could be relevant for reflective learning among researchers and practitioners when welfare technology should be implemented in a health care organization.Keywords: Dialogue meetings, implementation, reflection, test bed, welfare technology, participatory action research.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4496188 Overall Stability of Welded Q460GJ Steel Box Columns: Experimental Study and Numerical Simulations
Authors: Zhou Xiong, Kang Shao Bo, Yang Bo
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To date, high-performance structural steel has been widely used for columns in construction practices due to its significant advantages over conventional steel. However, the same design approach with conventional steel columns is still adopted in the design of high-performance steel columns. As a result, its superior properties cannot be fully considered in design. This paper conducts a test and finite element analysis on the overall stability behaviour of welded Q460GJ steel box columns. In the test, four steel columns with different slenderness and width-to-thickness ratio were compressed under an axial compression testing machine. And finite element models were established in which material nonlinearity and residual stress distributions of test columns were included. Then, comparisons were made between test results and finite element result, it showed that finite element analysis results are agree well with the test result. It means that the test and finite element model are reliable. Then, we compared the test result with the design value calculated by current code, the result showed that Q460GJ steel box columns have the higher overall buckling capacity than the design value. It is necessary to update the design curves for Q460GJ steel columns so that the overall stability capacity of Q460GJ box columns can be designed appropriately.
Keywords: Axial compression, Finite element analysis, Overall stability, Q460GJ steel, Welded box columns.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8536187 Investigating the Properties of Asphalt and Asphalt Mixture Based on the Effect of Waste Toner
Authors: P. I. Itoua, D. Sun, S. Shen
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This study aimed at investigating the properties of asphalt and mix asphalt based on the effects of waste toner sources (WT1 and WT2) with 8% dosage waste toner powders (WT). The test results included penetration, softening points, ductility, G*sinδ, G*/sinδ, Ideal cracking test (IDEAL-CT), and Ideal shear rutting test (IDEAL-RT). The results showed that the base binder with WT2 had a significantly higher viscosity value compared to the WT1 modified binder, and thus, higher energy for mixing and compaction is needed. Furthermore, the results of penetration, softening points, G*sinδ, and G*/sinδ were all affected by waste toner type. In terms of asphalt mixture, the IDEAL-RT test revealed that the addition of waste toner improved the rutting resistance of the asphalt mixture regardless of toner type. Further, CTindex values for waste toner-modified asphalt mixtures show no significant difference. Above all, WT-modified asphalt mixtures produced by the wet process have better rutting performance.
Keywords: Waste toner, waste toner-modified asphalt, asphalt mixture properties, IDEAL-RT test, IDEAL-CT test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1136186 An Experience Report on Course Teaching in Information Systems
Authors: Carlos Oliveira
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This paper is a criticism of the traditional model of teaching and presents alternative teaching methods, different from the traditional lecture. These methods are accompanied by reports of experience of their application in a class. It was concluded that in the lecture, the student has a low learning rate and that other methods should be used to make the most engaging learning environment for the student, contributing (or facilitating) his learning process. However, the teacher should not use a single method, but rather a range of different methods to ensure the learning experience does not become repetitive and fatiguing for the student.
Keywords: Educational practices, experience report, IT in education, teaching methods.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11006185 4D Flight Trajectory Optimization Based on Pseudospectral Methods
Authors: Kouamana Bousson, Paulo Machado
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The optimization and control problem for 4D trajectories is a subject rarely addressed in literature. In the 4D navigation problem we define waypoints, for each mission, where the arrival time is specified in each of them. One way to design trajectories for achieving this kind of mission is to use the trajectory optimization concepts. To solve a trajectory optimization problem we can use the indirect or direct methods. The indirect methods are based on maximum principle of Pontryagin, on the other hand, in the direct methods it is necessary to transform into a nonlinear programming problem. We propose an approach based on direct methods with a pseudospectral integration scheme built on Chebyshev polynomials.Keywords: Pseudospectral Methods, Trajectory Optimization, 4DTrajectories
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23986184 Construct Pairwise Test Suites Based on the Bak-Sneppen Model of Biological Evolution
Authors: Jianjun Yuan, Changjun Jiang
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Pairwise testing, which requires that every combination of valid values of each pair of system factors be covered by at lease one test case, plays an important role in software testing since many faults are caused by unexpected 2-way interactions among system factors. Although meta-heuristic strategies like simulated annealing can generally discover smaller pairwise test suite, they may cost more time to perform search, compared with greedy algorithms. We propose a new method, improved Extremal Optimization (EO) based on the Bak-Sneppen (BS) model of biological evolution, for constructing pairwise test suites and define fitness function according to the requirement of improved EO. Experimental results show that improved EO gives similar size of resulting pairwise test suite and yields an 85% reduction in solution time over SA.Keywords: Covering Arrays, Extremal Optimization, Simulated Annealing, Software Testing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17706183 Small Signal Stability Assessment of MEPE Test System in Free and Open Source Software
Authors: Kyaw Myo Lin
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This paper presents small signal stability study carried over the 140-Bus, 31-Machine, 5-Area MEPE system and validated on free and open source software: PSAT. Well-established linearalgebra analysis, eigenvalue analysis, is employed to determine the small signal dynamic behavior of test system. The aspects of local and interarea oscillations which may affect the operation and behavior of power system are analyzed. Eigenvalue analysis is carried out to investigate the small signal behavior of test system and the participation factors have been determined to identify the participation of the states in the variation of different mode shapes. Also, the variations in oscillatory modes are presented to observe the damping performance of the test system.
Keywords: Eigenvalue analysis, Mode shapes, MEPE test system, Participation factors, Power System oscillations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24196182 Design of the Large Dimension Cold Shield Cooled by G-M Cryocooler
Authors: Gong Jie, Yu Qianxu, Liu Min, Shan Weiwei
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The design of methods of the 20 K large dimension cold shield used for infrared radiation demarcating in space environment simulation test were introduced in this paper. The cold shield were cooled by five G-M cryocoolers , and the dimension of the cold shield is the largest in our country.Cold shield installation and distribution and compensator for contraction on cooling were introduced detailedly. The temperature distribution and cool-down time of cold shield surface were also calculated and analysed in this paper. The design of cold shield resolves the difficulty of compensator for contraction on cooling successfully. Test results show that the actual technical performance indicators of cold shield met and exceeded the design requirements.
Keywords: cold shield, G-M cryocooler,infrared radiometer demarcating, satellite, space environment simulation equipments
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16786181 Enhancing Rural Agricultural Value Chains through Electric Mobility Services in Ethiopia
Authors: Clemens Pizzinini, Philipp Rosner, David Ziegler, Markus Lienkamp
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Transportation is a constitutional part of most supply and value chains in modern economies. Smallholder farmers in rural Ethiopia face severe challenges along their supply and value chains. In particular, suitable, affordable, and available transport services are in high demand. To develop context-specific technical solutions, a problem-to-solution methodology based on the interaction with technology is developed. With this approach, we fill the gap between proven transportation assessment frameworks and general user-centered techniques. Central to our approach is an electric test vehicle that is implemented in rural supply and value chains for research, development, and testing. Based on our objective and the derived methodological requirements, a set of existing methods is selected. Local partners are integrated in an organizational framework that executes major parts of this research endeavour in Arsi Zone, Oromia Region, Ethiopia.
Keywords: Agricultural value chain, participatory methods, agile methods, sub-Saharan Africa, Ethiopia, electric vehicle, transport service.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1406180 Development of Elementary Literacy in the Czech Republic
Authors: Iva Košek Bartošová
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There is great attention being paid in the field of development of first reading, thus early literacy skills in the Czech Republic. Yet inconclusive results of PISA and PIRLS force us to think over the teacher´s work, his/her roles in the education process and methods and forms used in lessons. There is also a significant importance to monitor the family environment and the pupil, themselves. The aim of the publishing output is to focus on one side dealing with methods of practicing reading technique and their results in the process of comprehension. In the first part of the contribution there are the goals of development of reading literacy and the methods used in reading practice in some EU countries and a follow-up comparison of research implemented by the help of modern technology of an eye tracker device in the year 2015 and a research conducted at the Institute of Education and Psychological Counselling of the Czech Republic in the year 2011/12. These are the results of a diagnostic test of reading in first classes of primary schools, taught by the genetic method and analytic-synthetic method. The results show that in the first stage of practice there are no statistically significant differences between any researched subjects taught by different methods of reading practice (with the use of several diagnostic texts focused on reading technique and its comprehension). Different results are shown at the end of Grade One and during Grade Two of primary school.
Keywords: Elementary literacy, eye tracker device, diagnostic reading tests, reading teaching method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10746179 Modeling and Investigation of Elongation in Free Explosive Forming of Aluminum Alloy Plate
Authors: R. Alipour, F.Najarian
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Because of high ductility, aluminum alloys, have been widely used as an important base of metal forming industries. But the main week point of these alloys is their low strength so in forming them with conventional methods like deep drawing, hydro forming, etc have been always faced with problems like fracture during of forming process. Because of this, recently using of explosive forming method for forming of these plates has been recommended. In this paper free explosive forming of A2024 aluminum alloy is numerically simulated and during it, explosion wave propagation process is studied. Consequences of this simulation can be effective in prediction of quality of production. These consequences are compared with an experimental test and show the superiority of this method to similar methods like hydro forming and deep drawing.
Keywords: Free explosive forming, CEL, Johnson cook.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22996178 Lubricating Grease from Waste Cooking Oil and Waste Motor Sludge
Authors: Aseem Rajvanshi, Pankaj Kumar Pandey
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Increase in population has increased the demand of energy to fulfill all its needs. This will result in burden on fossil fuels especially crude oil. Waste oil due to its disposal problem creates environmental degradation. In this context, this paper studies utilization of waste cooking oil and waste motor sludge for making lubricating grease. Experimental studies have been performed by variation in time and concentration of mixture of waste cooking oil and waste motor sludge. The samples were analyzed using penetration test (ASTM D-217), dropping point (ASTM D-566), work penetration (ASTM D-217) and copper strip test (ASTM D-408). Among 6 samples, sample 6 gives the best results with a good drop point and a fine penetration value. The dropping point and penetration test values were found to be 205 °C and 315, respectively. The penetration value falls under the category of NLGI (National Lubricating Grease Institute) consistency number 1.Keywords: Crude oil, copper strip corrosion test, dropping point, penetration test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30876177 The Influence of Substrate Bias on the Mechanical Properties of a W- and S-containing DLC-based Solid-lubricant Film
Authors: Guojia Ma, Guoqiang Lin, Shuili Gong, Gang Sun, Dawang Wang
Abstract:
A diamond-like carbon (DLC) based solid-lubricant film was designed and DLC films were successfully prepared using a microwave plasma enhanced magnetron sputtering deposition technology. Post-test characterizations including Raman spectrometry, X-ray diffraction, nano-indentation test, adhesion test, friction coefficient test were performed to study the influence of substrate bias voltage on the mechanical properties of the W- and S-doped DLC films. The results indicated that the W- and S-doped DLC films also had the typical structure of DLC films and a better mechanical performance achieved by the application of a substrate bias of -200V.Keywords: Adhesive Strength, Coefficient of Friction, Substrate Bias, W- and S-doped DLC film
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