Search results for: Accelerated life test

Authors: Deepak R. Bhat, Netra P. Bhandery, Ryuichi Yatabe

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Strength recovery effect from the residual-state of shear is not well address in scientific literature. Torsional ring shear strength recovery tests on kaolin clay using rest periods up to 30 days are performed at the effective normal stress 100kN/m2. Test results shows that recovered strength measured in the laboratory is slightly noticeable after rest period of 3 days, but recovered strength lost after very small shear displacement. This paper mainly focused on the strength recovery phenomenon from the residual strength of kaolin clay based on torsional ring shear test results. Mechanisms of recovered strength are also discussed.

Keywords: Kaolin clay, Residual strength, Strength recovery, Torsional ring shear test.

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Authors: Angela Unna Chukwu, Samuel Oluwafemi Oyamakin

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We proposed a Hyperbolic Gompertz Growth Model (HGGM), which was developed by introducing a shape parameter (allometric). This was achieved by convoluting hyperbolic sine function on the intrinsic rate of growth in the classical gompertz growth equation. The resulting integral solution obtained deterministically was reprogrammed into a statistical model and used in modeling the height and diameter of Pines (Pinus caribaea). Its ability in model prediction was compared with the classical gompertz growth model, an approach which mimicked the natural variability of height/diameter increment with respect to age and therefore provides a more realistic height/diameter predictions using goodness of fit tests and model selection criteria. The Kolmogorov Smirnov test and Shapiro-Wilk test was also used to test the compliance of the error term to normality assumptions while the independence of the error term was confirmed using the runs test. The mean function of top height/Dbh over age using the two models under study predicted closely the observed values of top height/Dbh in the hyperbolic gompertz growth models better than the source model (classical gompertz growth model) while the results of R2, Adj. R2, MSE and AIC confirmed the predictive power of the Hyperbolic Gompertz growth models over its source model.

Keywords: Height, Dbh, forest, Pinus caribaea, hyperbolic, gompertz.

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Authors: Christian A. Romero, Tanja Grkovic, John. R. J. French, D. İpek. Kurtböke, Ronald J. Quinn

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A high-throughput and automated 1H NMR metabolic fingerprinting dereplication approach was used to accelerate the discovery of unknown bioactive secondary metabolites. The applied dereplication strategy accelerated the discovery of new natural products, provided rapid and competent identification and quantification of the known secondary metabolites and avoided time-consuming isolation procedures. The effectiveness of the technique was demonstrated by the isolation and elucidation of arglecins B (1), C (2) and actinofuranosin A (3) from a termite-gut associated Streptomyces sp. (USC 597) grown under solid state fermentation. The structures of these compounds were elucidated by extensive interpretation of 1H, 13C and 2D NMR spectroscopic data. These represent the first report of arglecin analogues isolated from a termite gut-associated Streptomyces species.

Keywords: Actinomycetes, actinofuranosin, antibiotics, arglecins, NMR spectroscopy.

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Authors: Thanasis K. Barlas, Helge A. Madsen

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A novel Active Flap System (AFS) has been developed at DTU Wind Energy, as a result of a 3-year R&D project following almost 10 years of innovative research in this field. The full scale AFS comprises an active deformable trailing edge has been tested at the unique rotating test facility at the Risø Campus of DTU Wind Energy in Denmark. The design and instrumentation of the wing section and the AFS are described. The general description and objectives of the rotating test rig at the Risø campus of DTU are presented, along with an overview of sensors on the setup and the test cases. The post-processing of data is discussed and results of steady, flap step and azimuth control flap cases are presented.

Keywords: morphing, adaptive, flap, smart blade, wind turbine.

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Authors: M. Govindarajan

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Text Mining is around applying knowledge discovery techniques to unstructured text is termed knowledge discovery in text (KDT), or Text data mining or Text Mining. In decision tree approach is most useful in classification problem. With this technique, tree is constructed to model the classification process. There are two basic steps in the technique: building the tree and applying the tree to the database. This paper describes a proposed C5.0 classifier that performs rulesets, cross validation and boosting for original C5.0 in order to reduce the optimization of error ratio. The feasibility and the benefits of the proposed approach are demonstrated by means of medial data set like hypothyroid. It is shown that, the performance of a classifier on the training cases from which it was constructed gives a poor estimate by sampling or using a separate test file, either way, the classifier is evaluated on cases that were not used to build and evaluate the classifier are both are large. If the cases in hypothyroid.data and hypothyroid.test were to be shuffled and divided into a new 2772 case training set and a 1000 case test set, C5.0 might construct a different classifier with a lower or higher error rate on the test cases. An important feature of see5 is its ability to classifiers called rulesets. The ruleset has an error rate 0.5 % on the test cases. The standard errors of the means provide an estimate of the variability of results. One way to get a more reliable estimate of predictive is by f-fold –cross- validation. The error rate of a classifier produced from all the cases is estimated as the ratio of the total number of errors on the hold-out cases to the total number of cases. The Boost option with x trials instructs See5 to construct up to x classifiers in this manner. Trials over numerous datasets, large and small, show that on average 10-classifier boosting reduces the error rate for test cases by about 25%.

Keywords: C5.0, Error Ratio, text mining, training data, test data.

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Authors: Son Tung Pham, William Prince

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The objective of this work was to examine the changes in non destructive properties caused by carbonation of CEM II mortar. Samples of CEM II mortar were prepared and subjected to accelerated carbonation at 20°C, 65% relative humidity and 20% CO2 concentration. We examined the evolutions of the gas permeability, the thermal conductivity, the thermal diffusivity, the volume of the solid phase by helium pycnometry, the longitudinal and transverse ultrasonic velocities. The principal contribution of this work is that, apart of the gas permeability, changes in other non destructive properties have never been studied during the carbonation of cement materials. These properties are important in predicting/measuring the durability of reinforced concrete in CO2 environment. The carbonation depth and the porosity accessible to water were also reported in order to explain comprehensively the changes in non destructive parameters.

Keywords: Carbonation, cement mortar, longitudinal and transverse ultrasonic velocities, non destructive tests.

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Authors: Jehad Al Dallal

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An application framework provides a reusable design and implementation for a family of software systems. If the framework contains defects, the defects will be passed on to the applications developed from the framework. Framework defects are hard to discover at the time the framework is instantiated. Therefore, it is important to remove all defects before instantiating the framework. In this paper, two measures for the adequacy of an object-oriented system-based testing technique are introduced. The measures assess the usefulness and uniqueness of the testing technique. The two measures are applied to experimentally compare the adequacy of two testing techniques introduced to test objectoriented frameworks at the system level. The two considered testing techniques are the New Framework Test Approach and Testing Frameworks Through Hooks (TFTH). The techniques are also compared analytically in terms of their coverage power of objectoriented aspects. The comparison study results show that the TFTH technique is better than the New Framework Test Approach in terms of usefulness degree, uniqueness degree, and coverage power.

Keywords: Object-oriented framework, object-oriented framework testing, test case generation, testing adequacy.

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Authors: Robert Cep, Jana Petru, Lenka Cepova, Tomas Zlamal

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Paper is dealing by testing of IN23 ceramic cutting tools at irregular shocks at special fixture - interrupted cut simulator. Standard tests provided at fixture were at regular interrupted cut at 4 slats by 90°. These new tests will be at irregular cut for 1 slat, 2 slats against each other, 2 slats side by side, 3 slats and 4 slats. The main goal is check if irregular shocks have influence at mechanical and thermal shock at tool life of cutting inserts. 

Keywords: Test, Ceramic Cutting Tool, Irregular Interrupted Cut.

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Authors: M. F. V. Montezuma, E. P. Deus, M. C. Carvalho

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Steel bridges are normally subjected to random loads with different traffic frequencies. They are structures with dynamic behavior and are subject to fatigue failure process, where the nucleation of a crack, growth and failure can occur. After locating and determining the size of an existing fault, it is important to predict the crack propagation and the convenient time for repair. Therefore, fracture mechanics and fatigue concepts are essential to the right approach to the problem. To study the fatigue crack growth, a computational code was developed by using the root mean square (RMS) and the cycle-by-cycle models. One observes the variable amplitude loading influence on the life structural prediction. Different loads histories and initial crack length were considered as input variables. Thus, it was evaluated the dispersion of results of the expected structural life choosing different initial parameters.

Keywords: Fatigue crack propagation, life prediction, variable loadings, steel bridges.

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Authors: Nureni O. Adeboye, Dawud A. Agunbiade

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This research attempts to investigate the effects of heteroscedasticity and periodicity in a Panel Data Regression Model (PDRM) by extending previous works on balanced panel data estimation within the context of fitting PDRM for Banks audit fee. The estimation of such model was achieved through the derivation of Joint Lagrange Multiplier (LM) test for homoscedasticity and zero-serial correlation, a conditional LM test for zero serial correlation given heteroscedasticity of varying degrees as well as conditional LM test for homoscedasticity given first order positive serial correlation via a two-way error component model. Monte Carlo simulations were carried out for 81 different variations, of which its design assumed a uniform distribution under a linear heteroscedasticity function. Each of the variation was iterated 1000 times and the assessment of the three estimators considered are based on Variance, Absolute bias (ABIAS), Mean square error (MSE) and the Root Mean Square (RMSE) of parameters estimates. Eighteen different models at different specified conditions were fitted, and the best-fitted model is that of within estimator when heteroscedasticity is severe at either zero or positive serial correlation value. LM test results showed that the tests have good size and power as all the three tests are significant at 5% for the specified linear form of heteroscedasticity function which established the facts that Banks operations are severely heteroscedastic in nature with little or no periodicity effects.

Keywords: Audit fee, heteroscedasticity, Lagrange multiplier test, periodicity.

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Authors: Pavel Zikl, Nikola Holoubková, Hana Karásková, Tereza B. Veselíková

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The article presents the research results focused on comparing the level of gross motor skills in children with mild intellectual disabilities and intact children. The data collection used the standard test (Test of Gross Motor Development). The research sample consisted of a total of 114 students with an average age of 10 years. The results present the differences between the two groups of students in locomotor skills and object control skills. The presented results can serve as a basis for better targeting of special-pedagogical support for children with mild intellectual disabilities and as a basis for innovation of the curriculum for this group of children, as well as a basis for further research activities in this area.

Keywords: Gross motor, mild intellectual disability, Test of Gross Motor Development.

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Authors: Khadiga Kahwa, Aniza Ismail

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Depression, anxiety, and stress are associated with decreased role functioning, productivity, and quality of life. International students are more prone to psychological distress as they face many stressors while studying abroad. The objectives of the study were to determine the prevalence and associated factors of depression, anxiety, and stress among international students, their help-seeking behavior, and their awareness of the available on-campus mental support services. A cross-sectional study with a purposive sampling method was performed on 280 international students at Universiti Kebangsaan Malaysia (UKM) between the age of 18 and 35 years. The Depression Anxiety Stress Scale-21 (DASS-21) questionnaire was used anonymously to assess the mental health of students. Socio-demographic, help-seeking behavior, and awareness data were obtained. Independent sample t-test, one-way ANOVA test, and multiple linear regression were used to explore associated factors. The overall prevalence of depression, anxiety, and stress among international students were 58.9%, 71.8%, and 53.9%, respectively. Age was significantly associated with depression and anxiety. Ethnicity showed a significant association with depression and stress. No other factors were found to be significantly associated with psychological distress. Only 9.6% of the international students had sought help from on-campus mental support services. Students who were aware of the presence of such services were only 21.4% of the participants. In conclusion, this study addressed the gap in the literature on the mental health of international students and provided data that could be used in intervention programs to improve the mental health of the increasing number of international students in Malaysia.

Keywords: Anxiety, depression, stress, help-seeking behavior, students.

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Authors: Anna R. Alyusheva, Veronika V. Nourkova

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The aim of the present paper is to investigate the interdependency among ego-identity status, autobiographical memory and cultural life story schema. The study shows considerable differences between autobiographical memory characteristics and “family script", which is typical for participants (adolescents, M age years = 17.84, SD = 1.18, N = 58), with different ego-identity statuses. Participants with diffused ego-identity status recalled fewer autobiographical memories. Additionally, this group of participants recalled fewer events from their parents- life. Participants with moratorium ego-identity status dated their first recollections to a later age than others, and recalled fewer memories relating to their childhood. Participants with achieved identity status recalled more self-defining memories and events from their parents- life. They used more functions from the autobiographical memory. There weren-t any significant differences between the foreclosed identity status group and the others. These findings support the idea of a bidirectional relation between culture, memory and self.

Keywords: Autobiographical memory, autobiographical narrative, cultural life script, ego-identity

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Authors: Ali Eryılmaz

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In this research it is aimed that the effect of some demographic factors on Turkish Adolescents' subjective well being is investigated. 432 adolescents who are 247 girls and 185 boys are participated in this study. They are ages 15-17, and also are high school students. The Positive and Negative Affect Scale and Life Satisfaction Scale are used for measuring adolescents' subjective well being. The ANOVA method is used in order to examine the effect of ages. For gender differences, independent t-test method is used, and finally the Pearson Correlation method is used so as to examine the effect of socio economic statues of adolescents' parents. According to results, there is no gender difference on adolescents' subjective well being. On the other hand, SES and age are effect significantly lover level on adolescents' subjective well being.

Keywords: Subjective wellbeing, adolescents, and age, gender, SES.

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Authors: Ya Hong Dong, Conrad T.C. Wong, S. Thomas Ng, James M.W. Wong

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Precast concrete has been widely adopted in public housing construction of Hong Kong since the mid-1980s. While pre-casting is considered an environmental friendly solution, there is lack of study to investigate the life cycle performance of precast concrete units. This study aims to bridge the knowledge gap by providing a comprehensive life cycle assessment (LCA) study for two precast elements namely façade and bathroom. The results show that raw material is the most significant contributor of environmental impact accounting for about 90% to the total impact. Furthermore, human health is more affected by the production of precast concrete than the ecosystems.

Keywords: Environment, green, LCA, LCIA, precast.

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Authors: Saranya Chularee, Tawa Chularee

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Successful intelligence (SI) is the integrated set of the ability needed to attain success in life, within individual-s sociocultural context. People are successfully intelligent by recognizing their strengths and weaknesses. They will find ways to strengthen their weakness and maintain their strength or even improve it. SI people can shape, select, and adapt to the environments by using balance of higher-ordered thinking abilities including; critical, creative, and applicative. Aims: The purposes of this study were to; 1) develop curriculum that promotes SI for nursing students, and 2) study the effectiveness of the curriculum development. Method: Research and Development was a method used for this study. The design was divided into two phases; 1) the curriculum development which composed of three steps (needs assessment, curriculum development and curriculum field trail), and 2) the curriculum implementation. In this phase, a pre-experimental research design (one group pretest-posttest design) was conducted. The sample composed of 49 sophomore nursing students of Boromarajonani College of Nursing, Surin, Thailand who enrolled in Nursing care of Health problem course I in 2011 academic year. Data were carefully collected using 4 instruments; 1) Modified essay questions test (MEQ) 2) Nursing Care Plan evaluation form 3) Group processing observation form (α = 0.74) and 4) Satisfied evaluation form of learning (α = 0.82). Data were analyzed using descriptive statistics and content analysis. Results: The results revealed that the sample had post-test average score of SI higher than pre-test average score (mean difference was 5.03, S.D. = 2.84). Fifty seven percentages of the sample passed the MEQ posttest at the criteria of 60 percentages. Students demonstrated the strategies of how to develop nursing care plan. Overall, students- satisfaction on teaching performance was at high level (mean = 4.35, S.D. = 0.46). Conclusion: This curriculum can promote the attribute of characteristic of SI person and was highly required to be continued.

Keywords: Curriculum Development, Nursing Education, Successful Intelligence, Thinking ability.

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Authors: Ebru Kavak Akpinar, Seda Toraman

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In the present work, the effective moisture diffusivity and activation energy were calculated using an infinite series solution of Fick-s diffusion equation. The results showed that increasing drying temperature accelerated the drying process. All drying experiments had only falling rate period. The average effective moisture diffusivity values varied from 2.807x10-10 to 6.977x10-10m2 s_1 over the temperature and velocity range. The temperature dependence of the effective moisture diffusivity for the thin layer drying of the ginger slices was satisfactorily described by an Arrhenius-type relationship with activation energy values of 19.313- 22.722 kJ.mol-1 within 40–70 °C and 0.8-3 ms-1 temperature range.

Keywords: Ginger, Drying, Activation energy, Moisture diffusivity.

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Authors: Nishanth Murugan, Mohammed Niyasdeen Nejaamtheen, S. Sounder Rajan

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The accelerated growth in aircraft industries desire effectual schemes, programs, innovative designs of advanced systems to accomplishing the augmenting need for home-free air transportation. In this paper, a contemporary conceptual design of an airplane has been proposed without landing gear systems in order to reducing accidents, time consumption, and to eliminating drawbacks by using superconducting levitation phenomenon. This invention of an airplane with superconductive material coating, on the solar plexus region assist to reduce weight by approximately 4% of the total takeoff weight, and cost effective. Moreover, we conjectured that superconductor landing system reduces ground friction, mission fuel, total drag, take-off and landing distance.

Keywords: Aircraft landing system, Magnetic levitation, Superconductors, Take-off and landing.

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Authors: Ahmed Amin Mousa, M. Abd El Salam

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The current study presents a proposed program for acquisition the skills and techniques needed to produce concept cartoon. The proposed program has been prepared for non-specialist students who have never used neither graphics nor animating software. It was presented to postgraduates in Faculty of Education for Early Childhood, Cairo University, during the spring term of the 2014-2015 academic year. The program works in three different aspects: Drawing and images editing, sound manipulation, and creating animation. In addition, the researchers have prepared a questionnaire for measuring the quality of the concept cartoons produced by the students. The questionnaire was used as a pre-test and post-test, and at the end of the study, a significant difference was determined in favour of post-test results.

Keywords: Cartoon, concept cartoon, kindergarten, animation.

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Authors: Lija Dukalska, Sandra Muizniece-Brasava, Irisa Murniece, Ilona Dabina-Bicka, Emils Kozlinskis, Svetlana Sarvi

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Experiments were carried out at the Faculty of Food Technology of Latvia University of Agriculture (LLU). Soft cheese Kleo produced in Latvia was packed in a biodegradable PLA without barrierproperties and VC999 BioPack lidding film PLA, coated with a barrier of pure silicon oxide (SiOx) and in combination with modified atmosphere (MAP) the influence on the shelf life was investigated and compared with some conventional (OPP, PE/PA, PE/OPA and Multibarrier 60) polymer film impact. Modified atmosphere consisted of carbon dioxide CO2 (E 290) 30% and nitrogen N2 (E 941) 70%. The analyzable samples were stored at the temperature of +4.0±0.5 °C up to 32 days- and analyzed before packaging and in the 0, 5th, 11th, 15th, 18th, 22nd, 25th, 29th and 32nd day of storage. The shelf life was extended along to 32 days, good outside appearance and lactic acid aroma was observed.

Keywords: Soft cheese, modified atmosphere, conventional andbiodegradable PLA film, shelf life

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Authors: Noppakit Nawalikit, Pattarasinee Bhattarakosol

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Since Software testing becomes an important part of Software development in order to improve the quality of software, many automation tools are created to help testing functionality of software. There are a few issues about usability of these tools, one is that the result log which is generated from tools contains useless information that the tester cannot use result log to communicate efficiently, or the result log needs to use a specific application to open. This paper introduces a new method, SBTAR that improves usability of automated test tools in a part of a result log. The practice will use the capability of tools named as IBM Rational Robot to create a customized function, the function would generate new format of a result log which contains useful information faster and easier to understand than using the original result log which was generated from the tools. This result log also increases flexibility by Microsoft Word or WordPad to make them readable.

Keywords: Software Automation Testing, Automated test tool, IBM Rational Robot.

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Authors: Harun Gülan, Muhsin Tunay Gencoglu, Mehmet Cebeci

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The main function of the insulators used in high voltage (HV) transmission lines is to insulate the energized conductor from the pole and hence from the ground. However, when the insulators fail to perform this insulation function due to various effects, failures occur. The deterioration of the insulation results either from breakdown or surface flashover. The surface flashover is caused by the layer of pollution that forms conductivity on the surface of the insulator, such as salt, carbonaceous compounds, rain, moisture, fog, dew, industrial pollution and desert dust. The source of the majority of failures and interruptions in HV lines is surface flashover. This threatens the continuity of supply and causes significant economic losses. Pollution flashover in HV insulators is still a serious problem that has not been fully resolved. In this study, a water jet test system has been established in order to investigate the behavior of insulators under dirty conditions and to determine their flashover performance. Flashover behavior of the insulators is examined by applying impulse voltages in the test system. This study aims to investigate the insulator behaviour under high impulse voltages. For this purpose, a water jet test system was installed and experimental results were obtained over a real system and analyzed. By using the water jet test system instead of the actual insulator, the damage to the insulator as a result of the flashover that would occur under impulse voltage was prevented. The results of the test system performed an important role in determining the insulator behavior and provided predictability.

Keywords: Insulator, pollution flashover, high impulse voltage, water jet model.

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Authors: Mohammed Niyasdeen Nejaamtheen

Abstract:

The accelerated growth in aircraft industries desire effectual schemes, programs, innovative designs of advanced systems and facilities to accomplish the augmenting need for home-free air transportation. In this paper, a contemporary conceptual design of a cambered airfoil has been proposed in order to providing augmented effective lift force relative to the airplane, and to eliminating drawbacks and limitations of an airfoil in a commercial airplane by using a kind of smart materials. This invention of an unsymmetrical airfoil structure utilizes the amplified air momentum around the airfoil and increased camber length to providing improved aircraft performance and assist to enhancing the reliability of the aircraft components. Moreover, this conjectured design helps to reducing airplane weight and total drag.

Keywords: Collector electrode, corona electrode, Temperatureresponsive polymer and ultra-faims microchip.

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Authors: Mohammad I. Hossain, Omar F. Hamim

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This paper presents a case study on a pile integrity test for assessing the integrity of piles as well as a physical dimension (e.g., cross-sectional area, length), continuity, and consistency of the pile materials. The recent boom in the socio-economic condition of Bangladesh has given rise to the building of high-rise commercial and residential infrastructures. The advantage of the pile integrity test lies in the fact that it is possible to get an approximate indication regarding the quality of the sub-structure before commencing the construction of the super-structure. This paper aims at providing a classification of cast-in-situ piles based on characteristic reflectograms obtained using the Sonic Integrity Testing program for the sub-soil condition of Narayanganj, Bangladesh. The piles have been classified as 'Pile Type-1', 'Pile Type-2', 'Pile Type-3', 'Pile type-4', 'Pile Type-5' or 'Pile Type-6' from the visual observations of reflections from the generated stress waves by striking the pile head with a handheld hammer. With respect to construction quality and integrity, piles have been further classified into three distinct categories, i.e., satisfactory, may be satisfactory, and unsatisfactory.

Keywords: Cast-in-situ piles, characteristic reflectograms, pile integrity test, sonic integrity testing program.

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Authors: Ramirez D. Edgar I., Angeles H. José J., Ruiz C. Osvaldo, Jacobo A. Victor H., Ortiz P. Armando

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Knowledge of bone mechanical properties is important for bone substitutes design and fabrication, and more efficient prostheses development. The aim of this study is to characterize the viscoelastic behavior of bone specimens, through stress relaxation and fatigue tests performed to trabecular bone samples from bovine femoral heads. Relaxation tests consisted on preloading the samples at five different magnitudes and evaluate them for 1020 seconds, adjusting the results to a KWW mathematical model. Fatigue tests consisted of 700 load cycles and analyze their status at the end of the tests. As a conclusion we have that between relaxation stress and each preload there is linear relation and for samples with initial Young´s modulus greater than 1.5 GPa showed no effects due fatigue test loading cycles.

Keywords: Bone viscoelasticity, fatigue test, stress relaxation test, trabecular bone properties.

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Authors: Kalyan Kumar Mandal, Damodar Maity

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The degradation of concrete due to various hygrochemo- mechanical actions is inevitable for the structures particularly built to store water. Therefore, it is essential to determine the material properties of dam-like structures due to ageing to predict the behavior of such structures after a certain age. The degraded material properties are calculated by introducing isotropic degradation index. The predicted material properties are used to study the behavior of aged dam at different ages. The dam is modeled by finite elements and displacement and is considered as an unknown variable. The parametric study reveals that the displacement is quite larger for comparatively lower design life of the structure because the degradation of elastic properties depends on the design life of the dam. The stresses in dam cam be unexpectedly large at any age with in the design life. The outcomes of the present study indicate the importance of the consideration ageing effect of concrete exposed to water for the safe design of dam throughout its life time.

Keywords: Hygro-chemo-mechanical, isotropic degradation, finite element method, Koyna earthquake.

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Authors: Noelia González-Gálvez, María Carrasco Poyatos, Pablo Jorge Marcos Pardo, Yuri Feito

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Musculoskeletal injuries in school children could be reduced improving trunk strength and hamstring flexibility. Low levels of trunk muscle strength and hamstring flexibility may result in acute and musculoskeletal chronic diseases. The Pilates Method can be appropriate to improve these physical condition attributes and has been rarely employed by this social group. On the other hand, it has been shown that trunk strength and flexibility are different between genders, but there is no evidence about the effect of exercise programs designed to improve both items in school children. Therefore the objective of this study was to measure the effect of a six-week Pilates-based exercise program in 14 year old school children trunk strength and hamstring flexibility, establishing differences in gender. The sample was composed of 57 students divided into experimental group (EG; n=30) and control group (CG; n=27). Bench Trunk Curl test (BTC), Sörensen test and Toe-touch test (TT) were used to measure dynamic muscular resistance in trunk flexion, isometric strength in trunk extension and hamstring flexibility, respectively. EG utilized the Pilates exercise program during six-weeks (2 days/week, 55minutes/session). After this period of training, EG improved trunk strength and hamstring flexibility significantly but there were no significant differences within CG. Although boys were better in BTC test and girls were better in TT test, there were no significant differences between them.

Keywords: Teens, school, trunk muscular resistance, intervention, physical performance, abdominal, back.

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Authors: S. Silverstone, J. Phadungtin

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Today-s Wi Fi generation utilize the latest technology in their daily lives. Instructors at National University, the second largest non profit private institution of higher learning in California, are incorporating these new tools to modify their Online class formats to better accommodate these new skills in their distance education delivery modes. The University provides accelerated learning in a one-course per month format both Onsite and Online. Since there has been such a significant increase in Online classes over the past three years, and it is expected to grow even more over the over the next five years, Instructors cannot afford to maintain the status quo and not take advantage of these new options. It is at the discretion of the instructors which accessory they use and how comfortable and familiar they are with the technology. This paper explores the effects and summarizes students- comments of some of these new technological options which have been recently provided in order to make students- online learning experience more exciting and meaningful.

Keywords: Asynchronous chats, synchronous learning, VoIP.

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Authors: Ivan Struhár, Martin Sebera, Lenka Dovrtělová

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The aim of this study was to find out if the special type of exercise with elastic cord can improve the level of postural stability. The exercise programme was conducted twice a week for 3 months. The participants were randomly divided into an experimental group and a control group. The electronic balance board was used for testing of postural stability. All participants trained for 18 hours at the time of experiment without any special form of coordination programme. The experimental group performed 90 minutes plus of coordination exercise. The result showed that differences between pre-test and post-test occurred in the experimental group. It was used the nonparametric Wilcoxon t-test for paired samples (p=0.012; the significance level 95%). We calculated effect size by Cohen´s d. In the experimental group d is 1.96 which indicates a large effect. In the control group d is 0.04 which confirms no significant improvement.

Keywords: Balance board, balance training, coordination, stability.

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Authors: G. Bago, P. Hedbávný, M. Kalichová

Abstract:

The aim of the contribution is to project and consequently verify a testing battery which in practice would facilitate the selection of talented gymnasts for current concept of men´ s gymnastics. Based on study of professional literature a test array consisting of three parts projected – power testing, speed testing and flexibility testing– was projected. The evaluating scales used in the tests are standardized. This test array was applied to girls aged 6 - 7 during recruitment for Sokol Brno I. and SG Pelhrimov Gymnastic Club. After 6 months of training activity the projected set of tests was applied again. The results were evaluated through observation and questionnaire and they were consequently transformed into charts. Recommendation for practice was proposed based on these results.

Keywords: Talent selection, sports gymnastics, power testing, speed testing, flexibility testing.

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