Search results for: size–classes
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6727

Search results for: size–classes

6367 An Empirical Evaluation of Performance of Machine Learning Techniques on Imbalanced Software Quality Data

Authors: Ruchika Malhotra, Megha Khanna

Abstract:

The development of change prediction models can help the software practitioners in planning testing and inspection resources at early phases of software development. However, a major challenge faced during the training process of any classification model is the imbalanced nature of the software quality data. A data with very few minority outcome categories leads to inefficient learning process and a classification model developed from the imbalanced data generally does not predict these minority categories correctly. Thus, for a given dataset, a minority of classes may be change prone whereas a majority of classes may be non-change prone. This study explores various alternatives for adeptly handling the imbalanced software quality data using different sampling methods and effective MetaCost learners. The study also analyzes and justifies the use of different performance metrics while dealing with the imbalanced data. In order to empirically validate different alternatives, the study uses change data from three application packages of open-source Android data set and evaluates the performance of six different machine learning techniques. The results of the study indicate extensive improvement in the performance of the classification models when using resampling method and robust performance measures.

Keywords: change proneness, empirical validation, imbalanced learning, machine learning techniques, object-oriented metrics

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6366 Stabilization of Transition Metal Chromite Nanoparticles in Silica Matrix

Authors: J. Plocek, P. Holec, S. Kubickova, B. Pacakova, I. Matulkova, A. Mantlikova, I. Němec, D. Niznansky, J. Vejpravova

Abstract:

This article presents summary on preparation and characterization of zinc, copper, cadmium and cobalt chromite nano crystals, embedded in an amorphous silica matrix. The ZnCr2O4/SiO2, CuCr2O4/SiO2, CdCr2O4/SiO2 and CoCr2O4/SiO2 nano composites were prepared by a conventional sol-gel method under acid catalysis. Final heat treatment of the samples was carried out at temperatures in the range of 900–1200 °C to adjust the phase composition and the crystallite size, respectively. The resulting samples were characterized by Powder X-ray diffraction (PXRD), High Resolution Transmission Electron Microscopy (HRTEM), Raman/FTIR spectroscopy and magnetic measurements. Formation of the spinel phase was confirmed in all samples. The average size of the nano crystals was determined from the PXRD data and by direct particle size observation on HRTEM; both results were correlated. The mean particle size (reviewed by HRTEM) was in the range from ~ 4 to 46 nm. The results showed that the sol-gel method can be effectively used for preparation of the spinel chromite nano particles embedded in the silica matrix and the particle size is driven by the type of the cation A2+ in the spinel structure and the temperature of the final heat treatment. Magnetic properties of the nano crystals were found to be just moderately modified in comparison to the bulk phases.

Keywords: sol-gel method, nanocomposites, Rietveld refinement, Raman spectroscopy, Fourier transform infrared spectroscopy, magnetic properties, spinel, chromite

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6365 Different Approaches to Teaching a Database Course to Undergraduate and Graduate Students

Authors: Samah Senbel

Abstract:

Database Design is a fundamental part of the Computer Science and Information technology curricula in any school, as well as in the study of management, business administration, and data analytics. In this study, we compare the performance of two groups of students studying the same database design and implementation course at Sacred Heart University in the fall of 2018. Both courses used the same textbook and were taught by the same professor, one for seven graduate students and one for 26 undergraduate students (juniors). The undergraduate students were aged around 20 years old with little work experience, while the graduate students averaged 35 years old and all were employed in computer-related or management-related jobs. The textbook used was 'Database Systems, Design, Implementation, and Management' by Coronel and Morris, and the course was designed to follow the textbook roughly a chapter per week. The first 6 weeks covered the design aspect of a database, followed by a paper exam. The next 6 weeks covered the implementation aspect of the database using SQL followed by a lab exam. Since the undergraduate students are on a 16 week semester, we spend the last three weeks of the course covering NoSQL. This part of the course was not included in this study. After the course was over, we analyze the results of the two groups of students. An interesting discrepancy was observed: In the database design part of the course, the average grade of the graduate students was 92%, while that of the undergraduate students was 77% for the same exam. In the implementation part of the course, we observe the opposite: the average grade of the graduate students was 65% while that of the undergraduate students was 73%. The overall grades were quite similar: the graduate average was 78% and that of the undergraduates was 75%. Based on these results, we concluded that having both classes follow the same time schedule was not beneficial, and an adjustment is needed. The graduates could spend less time on design and the undergraduates would benefit from more design time. In the fall of 2019, 30 students registered for the undergraduate course and 15 students registered for the graduate course. To test our conclusion, the undergraduates spend about 67% of time (eight classes) on the design part of the course and 33% (four classes) on the implementation part, using the exact exams as the previous year. This resulted in an improvement in their average grades on the design part from 77% to 83% and also their implementation average grade from 73% to 79%. In conclusion, we recommend using two separate schedules for teaching the database design course. For undergraduate students, it is important to spend more time on the design part rather than the implementation part of the course. While for the older graduate students, we recommend spending more time on the implementation part, as it seems that is the part they struggle with, even though they have a higher understanding of the design component of databases.

Keywords: computer science education, database design, graduate and undergraduate students, pedagogy

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6364 Tensile Force Estimation for Real-Size Pre-Stressed Concrete Girder using Embedded Elasto-Magnetic Sensor

Authors: Junkyeong Kim, Jooyoung Park, Aoqi Zhang, Seunghee Park

Abstract:

The tensile force of Pre-Stressed Concrete (PSC) girder is the most important factor for evaluating the performance of PSC girder bridges. To measure the tensile force of PSC girder, several NDT methods were studied. However, conventional NDT method cannot be applied to the real-size PSC girder because the PS tendons could not be approached. To measure the tensile force of real-size PSC girder, this study proposed embedded EM sensor based tensile force estimation method. The embedded EM sensor could be installed inside of PSC girder as a sheath joint before the concrete casting. After curing process, the PS tendons were installed, and the tensile force was induced step by step using hydraulic jacking machine. The B-H loop was measured using embedded EM sensor at each tensile force steps and to compare with actual tensile force, the load cell was installed at each end of girder. The magnetization energy loss, that is the closed area of B-H loop, was decreased according to the increase of tensile force with regular pattern. Thus, the tensile force could be estimated by the tracking the change of magnetization energy loss of PS tendons. Through the experimental result, the proposed method can be used to estimate the tensile force of the in-situ real-size PSC girder bridge.

Keywords: tensile force estimation, embedded EM sensor, magnetization energy loss, PSC girder

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6363 A Numerical Study on the Seismic Performance of Built-Up Battened Columns

Authors: Sophia C. Alih, Mohammadreza Vafaei, Farnoud Rahimi Mansour, Nur Hajarul Falahi Abdul Halim

Abstract:

Built-up columns have been widely employed by practice engineers in the design and construction of buildings and bridges. However, failures have been observed in this type of columns in previous seismic events. This study analyses the performance of built-up columns with different configurations of battens when it is subjected to seismic loads. Four columns with different size of battens were simulated and subjected to three different intensities of axial load along with a lateral cyclic load. Results indicate that the size of battens influences significantly the seismic behavior of columns. Lower shear capacity of battens results in higher ultimate strength and ductility for built-up columns. It is observed that intensity of axial load has a significant effect on the ultimate strength of columns, but it is less influential on the yield strength. For a given drift value, the stress level in the centroid of smaller size battens is significantly more than that of larger size battens signifying damage concentration in battens rather than chords. It is concluded that design of battens for shear demand lower than code specified values only slightly reduces initial stiffness of columns; however, it improves seismic performance of battened columns.

Keywords: battened column, built-up column, cyclic behavior, seismic design, steel column

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6362 Bio Ethanol Production From the Co-Mixture of Jatropha Carcus L. Kernel Cake and Rice Straw

Authors: Felix U. Asoiro, Daniel I. Eleazar, Peter O. Offor

Abstract:

As a result of increasing energy demands, research in bioethanol has increased in recent years all through the world, in abide to partially or totally replace renewable energy supplies. The first and third generation feedstocks used for biofuel production have fundamental drawbacks. Waste rice straw and cake from second generation feedstock like Jatropha curcas l. kernel (JC) is seen as non-food feedstock and promising candidates for the industrial production of bioethanol. In this study, JC and rice husk (RH) wastes were characterized for proximate composition. Bioethanol was produced from the residual polysaccharides present in rice husk (RH) and Jatropha seed cake by sequential hydrolytic and fermentative processes at varying mixing proportions (50 g JC/50 g RH, 100 g JC/10 g RH, 100 g JC/20 g RH, 100 g JC/50 g RH, 100 g JC/100 g RH, 100 g JC/200 g RH and 200 g JC/100 g RH) and particle sizes (0.25, 0.5 and 1.00 mm). Mixing proportions and particle size significantly affected both bioethanol yield and some bioethanol properties. Bioethanol yield (%) increased with an increase in particle size. The highest bioethanol (8.67%) was produced at a mixing proportion of 100 g JC/50g RH at 0.25 mm particle size. The bioethanol had the lowest values of specific gravity and density of 1.25 and 0.92 g cm-3 and the highest values of 1.57 and 0.97 g cm-3 respectively. The highest values of viscosity (4.64 cSt) were obtained with 200 g JC/100 g RH, at 1.00 mm particle size. The maximum flash point and cloud point values were 139.9 oC and 23.7oC (100 g JC/200 g RH) at 1 mm and 0.5 mm particle sizes respectively. The maximum pour point value recorded was 3.85oC (100 g JC/50 g RH) at 1 mm particle size. The paper concludes that bioethanol can be recovered from JC and RH wastes. JC and RH blending proportions as well as particle sizes are important factors in bioethanol production.

Keywords: bioethanol, hydrolysis, Jatropha curcas l. kernel, rice husk, fermentation, proximate composition

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6361 Size-Controlled Synthesis of Bismuth Nanoparticles by Temperature Assisted Pulsed Laser Deposition

Authors: Ranjit A. Patil, Yung Liou, Yuan-Ron Ma

Abstract:

It has been observed that when the size of metals such as, Au, Zn, Ag, Cu, Te, and metal oxides is reduced to several nano-meters, it starts to show further interesting properties. These new properties boost the use of nano-structures to produce attractive functional materials or used as promising building blocks in electronic devices. Present work describes the synthesis of bismuth (Bi) nanoparticles (NP’s) having uniform morphology, high crystallinity, and single phase purity by the temperature assisted pulsed laser deposition (TAPLD). Pulsed Laser deposition (PLD) technique is one of the promising methods to synthesize nano-structures. It can provide the stable nucleation sites in orders of magnitudes higher than for MBE and sputtering deposition. The desired size of purely metallic Bi NP’s of can be easily controlled by adjusting the temperature of the substrate varying from 1000 C to 250 0C. When the temperatures of the substrate raised step wise the average size of Bi NP’s appeared to be increased by maintaining the uniform distribution of NP’s on the Si surfaces. The diameter range of NP’s is ~33-84 nm shows size distribution constrained in the limited range. The EDS results show that the 0D Bi NP’s synthesized at high temperature (250 0C) at a high vacuum still remained in a metallic phase. Moreover, XRD, TEM and SAED results showed that these Bi NP’s are hexagonal in crystalline in a space group R -3 m and no traces of bismuth oxide, confirming that Bi NP’s synthesized at wide range of temperatures persisted of the pure Bi-metallic phase.

Keywords: metal nano particles, bismuth, pulsed laser deposition (PLD), nano particles, temperature assisted growth

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6360 An Extra-Curricular Program to Enhance Student Outcome of a Class

Authors: Dong Jin Kang

Abstract:

Application of single board microcontrollers is an important skill even for non-electronic engineering major students. Arduino board is widely utilized in engineering classes of the Yeungnam University of South Korea. In those classes, students are subjected to learn how to use various sensor components related to motion, sound, light, and so on as well as physical quantities. Students are grouped into several teams, and each team consists of 4~5 students. Many students are not motivated enough to learn those skills. An extracurricular program was planned to improve this problem. The extracurricular program was held as an international boot camp where students from three different countries were invited to participate. 10 students groups were formed, and each team was consisted of students having different nationality. The camp was 4 days long and wrapped up with competitions. During the camp, every student was assigned to design and make a two wheel robot. The competition was carried out in two different areas; individual and group performances. As most skills dealt in the class are used to build the robot, students are much motivated to review the whole subjects of the class. All students were surveyed after the program. The survey shows that the skills studied in the class are greatly improved, and practically understood. Staying at the dormitory and teaming with international students are help students improve communication skills. Competition at the camp was found as a key element to inspire and attract students for voluntary participation.

Keywords: extracurricular program, robot, Arduino board, international camp, competition

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6359 Optimisation of a Dragonfly-Inspired Flapping Wing-Actuation System

Authors: Jia-Ming Kok, Javaan Chahl

Abstract:

An optimisation method using both global and local optimisation is implemented to determine the flapping profile which will produce the most lift for an experimental wing-actuation system. The optimisation method is tested using a numerical quasi-steady analysis. Results of an optimised flapping profile show a 20% increase in lift generated as compared to flapping profiles obtained by high speed cinematography of a Sympetrum frequens dragonfly. Initial optimisation procedures showed 3166 objective function evaluations. The global optimisation parameters - initial sample size and stage one sample size, were altered to reduce the number of function evaluations. Altering the stage one sample size had no significant effect. It was found that reducing the initial sample size to 400 would allow a reduction in computational effort to approximately 1500 function evaluations without compromising the global solvers ability to locate potential minima. To further reduce the optimisation effort required, we increase the local solver’s convergence tolerance criterion. An increase in the tolerance from 0.02N to 0.05N decreased the number of function evaluations by another 20%. However, this potentially reduces the maximum obtainable lift by up to 0.025N.

Keywords: flapping wing, optimisation, quasi-steady model, dragonfly

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6358 Phytoplankton Community and Saprobic Pollution Index of Warm Water Fishes Ponds at East of Golestan Province: Case Study: Gonbade Kavous City

Authors: Mehrdad Kamali-Sanzighi, Maziar Kamali-Sanzighi

Abstract:

The aim of this investigation is to study the phytoplankton and saprobic index at warm water fish ponds in the East of Golestan province, Gonbade Kavous city. Phytoplankton and ciliate sampling were done monthly during one season of culture. Finally, 39 genera from 7 classes of phytoplankton and 4 genera from the ciliate group were identified. Although, among different classes, Chlorophyceae, Cyanophyceae, Bacillariophyceae, Charophyceae, Chrysophyceae, Dinophyceae, and Euglenophyceae had the highest and lowest frequency percent of phytoplankton community with 23, 21, 20, 14, 11, 6 and 5 percent respectively. The results show that there are no significant differences between the saprobic index of different ponds (P > 0.05). But there are significant differences between the saprobic index value of different months and seasons during season culture (P < 0.05). Also, in current research, the saprobic index indicated the ß-mesosaprob water quality level. There was a general tends of decrease in the saprobic index value from the beginning to the end of the culture season. Parameters such as biomass increase of grower fishes, an increase of introduced chemical fertilizer and manure sedimentation, uneaten fish feed, fish fecal, and no regular exchangeable water resources are some of these changes' reasons.

Keywords: fish pond, Golestan Province, saprobi index, phytoplankton, water quality

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6357 Effect of Strength Class of Concrete and Curing Conditions on Capillary Absorption of Self-Compacting and Conventional Concrete

Authors: Emine Ebru Demirci, Remzi Şahin

Abstract:

The purpose of this study is to compare Self Compacting Concrete (SCC) and Conventional Concrete (CC), which are used in beams with dense reinforcement, in terms of their capillary absorption. During the comparison of SCC and CC, the effects of two different factors were also investigated: concrete strength class and curing condition. In the study, both SCC and CC were produced in three different concrete classes (C25, C50 and C70) and the other parameter (i.e curing condition) was determined as two levels: moisture and air curing. Beam dimensions were determined to be 200 x 250 x 3000 mm. Reinforcements of the beams were calculated and placed as 2ø12 for the top and 3ø12 for the bottom. Stirrups with dimension 8 mm were used as lateral rebar and stirrup distances were chosen as 10 cm in the confinement zone and 15 cm at the central zone. In this manner, densification of rebars in lateral cross-sections of beams and handling of SCC in real conditions were aimed. Concrete covers of the rebars were chosen to be equal in all directions as 25 mm. The capillary absorption measurements were performed on core samples taken from the beams. Core samples of ø8x16 cm were taken from the beginning (0-100 cm), middle (100-200 cm) and end (200-300 cm) region of the beams according to the casting direction of SCC. However core samples were taken from lateral surface of the beams. In the study, capillary absorption experiments were performed according to Turkish Standard TS EN 13057. It was observed that, for both curing environments and all strength classes of concrete, SCC’s had lower capillary absorption values than that of CC’s. The capillary absorption values of C25 class of SCC are 11% and 16% lower than that of C25 class of CC for air and moisture conditions, respectively. For C50 class, these decreases were 6% and 18%, while for C70 class, they were 16% and 9%, respectively. It was also detected that, for both SCC and CC, capillary absorption values of samples kept in moisture curing are significantly lower than that of samples stored in air curing. For CC’s; C25, C50 and C70 class moisture-cured samples were found to have 26%, 12% and 31% lower capillary absorption values, respectively, when compared to the air-cured ones. For SCC’s; these values were 30%, 23% and 24%, respectively. Apart from that, it was determined that capillary absorption values for both SCC and CC decrease with increasing strength class of concrete for both curing environments. It was found that, for air cured CC, C50 and C70 class of concretes had 39% and 63% lower capillary absorption values compared to the C25 class of concrete. For the same type of concrete samples cured in the moisture environment, these values were found to be 27% and 66%. It was found that for SCC samples, capillary absorption value of C50 and C70 concretes, which were kept in air curing, were 35% and 65% lower than that of C25, while for moisture-cured samples these values were 29% and 63%, respectively. When standard deviations of the capillary absorption values are compared for core samples obtained from the beginning, middle and end of the CC and SCC beams, it was found that, in all three strength classes of concrete, the variation is much smaller for SCC than CC. This demonstrated that SCC’s had more uniform character than CC’s.

Keywords: self compacting concrete, reinforced concrete beam, capillary absorption, strength class, curing condition

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6356 Electrochemical Synthesis of Copper Nanoparticles

Authors: Juan Patricio Ibáñez, Exequiel López

Abstract:

A method for synthesizing copper nanoparticles through an electrochemical approach is proposed, employing surfactants to stabilize the size of the newly formed nanoparticles. The electrolyte was made up of a matrix of H₂SO₄ (190 g/L) having Cu²⁺ (from 3.2 to 9.5 g/L), sodium dodecyl sulfate -SDS- (from 0.5 to 1.0 g/L) and Tween 80 (from 0 to 7.5 mL/L). Tween 80 was used in a molar relation of 1 to 1 with SDS. A glass cell was used, which was in a thermostatic water bath to keep the system temperature, and the electrodes were cathodic copper as an anode and stainless steel 316-L as a cathode. This process was influenced by the control exerted through the initial copper concentration in the electrolyte and the applied current density. Copper nanoparticles of electrolytic purity, exhibiting a spherical morphology of varying sizes with low dispersion, were successfully produced, contingent upon the chemical composition of the electrolyte and current density. The minimum size achieved was 3.0 nm ± 0.9 nm, with an average standard deviation of 2.2 nm throughout the entire process. The deposited copper mass ranged from 0.394 g to 1.848 g per hour (over an area of 25 cm²), accompanied by an average Faradaic efficiency of 30.8% and an average specific energy consumption of 4.4 kWh/kg. The chemical analysis of the product employed X-ray powder diffraction (XRD), while physical characteristics such as size and morphology were assessed using atomic force microscopy (AFM). It was identified that the initial concentration of copper and the current density are the variables defining the size and dispersion of the nanoparticles, as they serve as reactants in the cathodic half-reaction. The presence of surfactants stabilizes the nanoparticle size as their molecules adsorb onto the nanoparticle surface, forming a thick barrier that prevents mass transfer with the exterior and halts further growth.

Keywords: copper nanopowder, electrochemical synthesis, current density, surfactant stabilizer

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6355 An Examination of Teachers’ Interactive Whiteboards Use within the Scope of Technological, Pedagogical, and Content Knowledge (TPACK)

Authors: Ismail Celik, Pavlo Antonenko, Seyit Ahmet Kiray, Ismail Sahin

Abstract:

The aim of the present study was to thoroughly investigate the teachers’ interactive whiteboards (IWBs) use within the scope of the technological pedagogical and content knowledge (TPACK) framework based on the school practice observations of in-service teachers collected by pre-service teachers. In this study, teachers’ use of IWBs in their classes was investigated by using phenomenography, which is a qualitative research method design. The participants of this study consisted of teachers working in a province of Turkey. Within the scope of the study, 337 teachers from 61 different schools were observed by preservice teachers during School Experience classes. The teachers use the IWBs to review the points not understood by the students, to share knowledge, to enhance motivation, to maintain student participation/practice and for in-process, formative assessment. The problems teachers face while using the IWBs can be IWB-based (touchscreen problems/frozen image/lack of software), administration-based, student-based and teacher-based (lack of knowledge of use, need for technical support). It is considered that technological knowledge (TK) is important in solving the problems experienced with IWBs, and technological pedagogy knowledge (TPK) and technological content knowledge (TCK) are important in using the IWBs in an interactive and pedagogically meaningful way that uses IWBs affordances and is relevant to the instructional objectives.

Keywords: TPACK, technology integration, interactive whiteboard, technology in education

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6354 The Effects of Corporate Governance on Firm’s Financial Performance: A Study of Family and Non-family Owned Firms in Pakistan

Authors: Saad Bin Nasir

Abstract:

This research will examine the impact of corporate governance on firm performance in family and non-family owned firms in Pakistan. For the purpose of this research, corporate governance mechanisms which included are board size, board composition, leadership structure, board meetings are taken as independent variable and firm performance taken as dependent variable and it will be measured with return on asset and return on equity. Firm size and firm’s age will be taken as control variables. Secondary data will collect from audited annul reports of companies and panel data regression model will applied, to check the impact of corporate governance on firm performance.

Keywords: board size, board composition, Leadership Structure, board meetings, firm performance, family and non-family owned firms

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6353 Banking Performance and Political Economy: Using ARDL Model

Authors: Marwen Ghouil, Jamel Eddine Mkadmi

Abstract:

Banking performance is the pillar and goal of all banking activity and its impact on economic policy. First, researchers defined the principles for assessing and modeling bank performance, and then theories and models explaining bank performance were developed. The importance of credit as a means of financing businesses in most developing countries has led to questions about the effects of financial liberalisation on increased banking competition. In Tunisia, as in many other countries, the liberalization of financial services in general and of banks' activities has not ceased to evolve. The objective of this paper is to examine the determinants of banking performance for 8 Tunisian banks and their impact on economic policy during the Arab Spring. We used cointegration analysis and the ARDL Panel model, explaining using total assets, bank credits, guarantees, and bank size as performance drivers. The correlation analysis shows that there is a positive correlation relationship between total assets, bank credits, guarantees, and bank size and bank performance. Long-term empirical results show that bank loans, guarantees, bank size, and total assets have a positive and significant impact on bank performance. This means that bank credits, guarantees, bank size, and total assets are very important determinants of bank performance in Tunisia.

Keywords: bank performance, economic policy, finance, economic

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6352 Pibid and Experimentation: A High School Case Study

Authors: Chahad P. Alexandre

Abstract:

PIBID-Institutional Program of Scholarships to Encourage Teaching - is a Brazilian government program that counts today with 48.000 students. It's goal is to motivate the students to stay in the teaching undergraduate programs and to help fill the gap of 100.000 teachers that are needed today in the under graduated schools. The major lack of teachers today is in physics, chemistry, mathematics, and biology. At IFSP-Itapetininga we formatted our physics PIBID based on practical activities. Our students are divided in two São Paulo state government high schools in the same city. The project proposes class activities based on experimentation, observation and understanding of physical phenomena. The didactical experiments are always in relation with the content that the teacher is working, he is the supervisor of the program in the school. Always before an experiment is proposed a little questionnaire to learn about the students preconceptions and one is filled latter to evaluate if now concepts have been created. This procedure is made in order to compare their previous knowledge and how it changed after the experiment is developed. The primary goal of our project is to make the Physics class more attractive to the students and to develop in high school students the interest in learning physics and to show the relation of Physics to the day by day and to the technological world. The objective of the experimental activities is to facilitate the understanding of the concepts that are worked on classes because under experimentation the PIBID scholarship student stimulate the curiosity of the high school student and with this he can develop the capacity to understand and identify the physical phenomena with concrete examples. Knowing how to identify this phenomena and where they are present at the high school student life makes the learning process more significant and pleasant. This proposal make achievable to the students to practice science, to appropriate of complex, in the traditional classes, concepts and overcoming the common preconception that physics is something distant and that is present only on books. This preconception is extremely harmful in the process of scientific knowledge construction. This kind of learning – through experimentation – make the students not only accumulate knowledge but also appropriate it, also to appropriate experimental procedures and even the space that is provided by the school. The PIBID scholarship students, as future teachers also have the opportunity to try experimentation classes, to intervene in the classes and to have contact with their future career. This opportunity allows the students to make important reflection about the practices realized and consequently about the learning methods. Due to this project, we found out that the high school students stay more time focused in the experiment compared to the traditional explanation teachers´ class. As a result in a class, as a participative activity, the students got more involved and participative. We also found out that the physics under graduated students drop out percentage is smaller in our Institute than before the PIBID program started.

Keywords: innovation, projects, PIBID, physics, pre-service teacher experiences

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6351 Gluteal Augmentation: A Historical Perspective on Society's Fascination with Buttock Size

Authors: Shane R. Jackson

Abstract:

Gluteal augmentation with fat grafting, commonly referred to as the Brazilian Butt Lift, is the fastest-growing cosmetic surgical procedure, despite the risks and controversy that surrounds it. While many commentators attribute this rise in popularity with current societal trends towards public sharing of private life, the fascination with buttock size is in fact a much older human trait. By searching beyond medical literature and delving into historical sources, from ancient civilisations, through the Renaissance and Victorian eras to the ‘Instagram generation’ of the present day, this paper examines the differences – and similarities – in society’s ideal buttock shape and size. Furthermore, the ways in which these various cultures have altered their appearance to achieve this ideal are also examined, looking at the influence of the broader historical context. A deeper understanding of the historical, cultural and psychosocial factors that influence a patient’s desire for buttock augmentation allows the clinician to formulate a well-rounded surgical plan.

Keywords: augmentation, Brazilian butt lift, buttock, fat graft, gluteal

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6350 Calculation of the Added Mass of a Submerged Object with Variable Sizes at Different Distances from the Wall via Lattice Boltzmann Simulations

Authors: Nastaran Ahmadpour Samani, Shahram Talebi

Abstract:

Added mass is an important quantity in analysis of the motion of a submerged object ,which can be calculated by solving the equation of potential flow around the object . Here, we consider systems in which a square object is submerged in a channel of fluid and moves parallel to the wall. The corresponding added mass at a given distance from the wall d and for the object size s (which is the side of square object) is calculated via lattice Blotzmann simulation . By changing d and s separately, their effect on the added mass is studied systematically. The simulation results reveal that for the systems in which d > 4s, the distance does not influence the added mass any more. The added mass increases when the object approaches the wall and reaches its maximum value as it moves on the wall (d -- > 0). In this case, the added mass is about 73% larger than which of the case d=4s. In addition, it is observed that the added mass increases by increasing of the object size s and vice versa.

Keywords: Lattice Boltzmann simulation , added mass, square, variable size

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6349 Growth of Droplet in Radiation-Induced Plasma of Own Vapour

Authors: P. Selyshchev

Abstract:

The theoretical approach is developed to describe the change of drops in the atmosphere of own steam and buffer gas under irradiation. It is shown that the irradiation influences on size of stable droplet and on the conditions under which the droplet exists. Under irradiation the change of drop becomes more complex: the not monotone and periodical change of size of drop becomes possible. All possible solutions are represented by means of phase portrait. It is found all qualitatively different phase portraits as function of critical parameters: rate generation of clusters and substance density.

Keywords: irradiation, steam, plasma, cluster formation, liquid droplets, evolution

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6348 Morphometric Relationships of Length-Weight and Length-Length of Oreochromis aureus in Relation to Body Size and Condition Factor from Pakistan

Authors: Muhammad Naeem, Abdus Salam, Sumera Yasmin, Abir Ishtiaq

Abstract:

In the present study, eighty-three wild Oreochromis aureus of different body size ranging 5.3-14.6 cm in total length were collected from the River Chenab, District Muzzafer Garh, Pakistan to investigate the parameters of length –weight, length-length relationships and condition factor in relation to size. Each fish was measured and weighed on arrival at laboratory. Log transformed regressions were used to test the allometric growth. Length-weight relationship was found highly significant (r = 0.964; P < 0.01). The values of exponent “ b” in Length–weight regression (W=aL^b), deviated from 3, showing isometric growth (b = 2.75). Results for LLRs indicated that these are highly correlated (P < 0.001). Condition factor (K) found constant with increasing body weight, however, showed negative influence with increasing total length.

Keywords: lenght-weight, Oreochromis aureus, morphometric study

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6347 Hydrodynamics of Wound Ballistics

Authors: Harpreet Kaur, Er. Arjun, Kirandeep Kaur, P. K. Mittal

Abstract:

Simulation of a human body from 20% gelatin & 80% water mixture is examined from wound ballistics point of view. Parameters such as incapacitation energy & temporary to permanent cavity size & tools of hydrodynamics have been employed to arrive at a model of human body similar to the one adopted by NATO. Calculations using equations of motion yield a value of 339 µs in which a temporary cavity with maximum size settles down to permanent cavity. This occurs for a 10mm size bullets & settle down to permanent cavity in case of 4 different bullets i.e. 5.45, 5.56, 7.62,10 mm sizes The obtained results are in excellent agreement with the body as right circular cylinder of 15 cm height & 10 cm diameter. An effort is made here in this work to present a sound theoretical base to parameters commonly used in wound ballistics from field experience discussed by Col Coats & Major Beyer. Keywords. Gelatin, gunshot, hydrodynamic model, oscillation time, temporary cavity and permanent cavity, Wound Ballistic.

Keywords: gelatin, gunshot, wound, cavity

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6346 Segmentation of Liver Using Random Forest Classifier

Authors: Gajendra Kumar Mourya, Dinesh Bhatia, Akash Handique, Sunita Warjri, Syed Achaab Amir

Abstract:

Nowadays, Medical imaging has become an integral part of modern healthcare. Abdominal CT images are an invaluable mean for abdominal organ investigation and have been widely studied in the recent years. Diagnosis of liver pathologies is one of the major areas of current interests in the field of medical image processing and is still an open problem. To deeply study and diagnose the liver, segmentation of liver is done to identify which part of the liver is mostly affected. Manual segmentation of the liver in CT images is time-consuming and suffers from inter- and intra-observer differences. However, automatic or semi-automatic computer aided segmentation of the Liver is a challenging task due to inter-patient Liver shape and size variability. In this paper, we present a technique for automatic segmenting the liver from CT images using Random Forest Classifier. Random forests or random decision forests are an ensemble learning method for classification that operate by constructing a multitude of decision trees at training time and outputting the class that is the mode of the classes of the individual trees. After comparing with various other techniques, it was found that Random Forest Classifier provide a better segmentation results with respect to accuracy and speed. We have done the validation of our results using various techniques and it shows above 89% accuracy in all the cases.

Keywords: CT images, image validation, random forest, segmentation

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6345 Effect of High-Energy Ball Milling on the Electrical and Piezoelectric Properties of (K0.5Na0.5)(Nb0.9Ta0.1)O3 Lead-Free Piezoceramics

Authors: Chongtham Jiten, K. Chandramani Singh, Radhapiyari Laishram

Abstract:

Nanocrystalline powders of the lead-free piezoelectric material, tantalum-substituted potassium sodium niobate (K0.5Na0.5)(Nb0.9Ta0.1)O3 (KNNT), were produced using a Retsch PM100 planetary ball mill by setting the milling time to 15h, 20h, 25h, 30h, 35h and 40h, at a fixed speed of 250rpm. The average particle size of the milled powders was found to decrease from 12nm to 3nm as the milling time increases from 15h to 25h, which is in agreement with the existing theoretical model. An anomalous increase to 98nm and then a drop to 3nm in the particle size were observed as the milling time further increases to 30h and 40h respectively. Various sizes of these starting KNNT powders were used to investigate the effect of milling time on the microstructure, dielectric properties, phase transitions and piezoelectric properties of the resulting KNNT ceramics. The particle size of starting KNNT was somewhat proportional to the grain size. As the milling time increases from 15h to 25h, the resulting ceramics exhibit enhancement in the values of relative density from 94.8% to 95.8%, room temperature dielectric constant (εRT) from 878 to 1213, and piezoelectric charge coefficient (d33) from 108pC/N to 128pC/N. For this range of ceramic samples, grain size refinement suppresses the maximum dielectric constant (εmax), shifts the Curie temperature (Tc) to a lower temperature and the orthorhombic-tetragonal phase transition (Tot) to a higher temperature. Further increase of milling time from 25h to 40h produces a gradual degradation in the values of relative density, εRT, and d33 of the resulting ceramics.

Keywords: perovskite, dielectric, ceramics, high-energy milling

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6344 Economic Indicators as Correlates of Inward Foreign Direct Investment in Nigeria

Authors: C. F. Popoola, P. Osho, S. B. Babarinde

Abstract:

This study examined economic indicators as correlates of inward FDI. An exploratory research design was used to obtained annual published data on inflation rate, market size, exchange rate, political instability, human development, and infrastructure from Central Bank of Nigeria, National Bureau of Statistics, Nigerian Capital Market, Nigeria Institute of Social and Economic Research, and UNCTAD. Data generated were analyzed using Pearson correlation, analysis of variance and regression. The findings of the study revealed that market size (r = 0.852, p < 0.001), infrastructure (r = 0.264, p < 0.001), human development (r = 0.154, p < 0.01) and exchange rate ( r= 0.178, p < 0.05) correlate positively with inward FDI, while inflation rate (r = -0.88, p < 0.001), and political instability (r= -0.102, p < 0.05) correlate negatively with inward FDI. Findings also revealed that the economic indicators significantly predicted inward FDI (R2 = 0.913; F(1,19) = 29.40; p < 0.05) for Nigeria. It was concluded that exchange rate, market size, human development, and infrastructure positively related to inward FDI while the high level of inflation and political instability negatively related to inward FDI. Therefore, it was suggested that policy makers and government agencies should readdress steps and design policies that would encourage more FDI into the country.

Keywords: exchange rate, foreign direct investment, human development, inflation rate, infrastructure, market size, political instability

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6343 An Algorithm Based on Control Indexes to Increase the Quality of Service on Cellular Networks

Authors: Rahman Mofidi, Sina Rahimi, Farnoosh Darban

Abstract:

Communication plays a key role in today’s world, and to support it, the quality of service has the highest priority. It is very important to differentiate between traffic based on priority level. Some traffic classes should be a higher priority than other classes. It is also necessary to give high priority to customers who have more payment for better service, however, without influence on other customers. So to realize that, we will require effective quality of service methods. To ensure the optimal performance of the network in accordance with the quality of service is an important goal for all operators in the mobile network. In this work, we propose an algorithm based on control parameters which it’s based on user feedback that aims at minimizing the access to system transmit power and thus improving the network key performance indicators and increasing the quality of service. This feedback that is known as channel quality indicator (CQI) indicates the received signal level of the user. We aim at proposing an algorithm in control parameter criterion to study improving the quality of service and throughput in a cellular network at the simulated environment. In this work we tried to parameter values have close to their actual level. Simulation results show that the proposed algorithm improves the system throughput and thus satisfies users' throughput and improves service to set up a successful call.

Keywords: quality of service, key performance indicators, control parameter, channel quality indicator

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6342 Effect of High Volume processed Fly Ash on Engineering Properties of Concrete

Authors: Dhara Shah, Chandrakant Shah

Abstract:

As everyone knows, fly ash is a residual material we get upon energy production using coal. It has found numerous advantages for use in the concrete industry like improved workability, increased ultimate strength, reduced bleeding, reduced permeability, better finish and reduced heat of hydration. Types of fly ash depend on the type of coal and the coal combustion process. It is a pozzolanic material and has mainly two classes, F and C, based on the chemical composition. The fly ash used for this experimental work contains significant amount of lime and would be categorized as type F fly ash. Generally all types of fly ash have particle size less than 0.075mm. The fineness and lime content of fly ash are very important as they will affect the air content and water demand of the concrete, thereby affecting the durability and strength of the concrete. The present work has been done to optimize the use of fly ash to produce concrete with improved results and added benefits. A series of tests are carried out, analyzed and compared with concrete manufactured using only Portland cement as a binder. The present study is carried out for concrete mix with replacement of cement with different proportions of fly ash. Two concrete mixes M25 and M30 were studied with six replacements of cement with fly ash i.e. 40%, 45%, 50%, 55%, 60% and 65% for 7-day, 14-day, 28-day, 56-day and 90-day. Study focused on compressive strength, split tensile strength, modulus of elasticity and modulus of rupture of concrete. Study clearly revealed that cement replacement by any proportion of fly ash failed to achieve early strength. Replacement of 40% and 45% succeeded in achieving required flexural strength for M25 and M30 grade of concrete.

Keywords: processed fly ash, engineering properties of concrete, pozzolanic, lime content

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6341 Assessment and Control for Oil Aerosol

Authors: Chane-Yu Lai, Xiang-Yu Huang

Abstract:

This study conducted an assessment of sampling result by using the new development rotation filtration device (RFD) filled with porous media filters integrating the method of cyclone centrifugal spins. The testing system established for the experiment used corn oil and potassium sodium tartrate tetrahydrate (PST) as challenge aerosols and were produced by using an Ultrasonic Atomizing Nozzle, a Syringe Pump, and a Collison nebulizer. The collection efficiency of RFD for oil aerosol was assessed by using an Aerodynamic Particle Sizer (APS) and a Fidas® Frog. The results of RFD for the liquid particles condition indicated the cutoff size was 1.65 µm and 1.02 µm for rotation of 0 rpm and 9000 rpm, respectively, under an 80 PPI (pores per inch)foam with a thickness of 80 mm, and sampling velocity of 13.5 cm/s. As the experiment increased the foam thickness of RFD, the cutoff size reduced from 1.62 µm to 1.02 µm. However, when increased the foam porosity of RFD, the cutoff size reduced from 1.26 µm to 0.96 µm. Moreover, as increased the sampling velocity of RFD, the cutoff size reduced from 1.02 µm to 0.76 µm. These discrepancies of above cutoff sizes of RFD all had statistical significance (P < 0.05). The cutoff size of RFD for three experimental conditions of generated liquid oil particles, solid PST particles or both liquid oil and solid PST particles was 1.03 µm, 1.02 µm, or 0.99 µm, respectively, under a 80 PPI foam with thickness of 80 mm, rotation of 9000 rpm, and sampling velocity of 13.5 cm/s. In addition, under the best condition of the experiment, two hours of sampling loading, the RFD had better collection efficiency for particle diameter greater than 0.45 µm, under a 94 PPI nickel mesh with a thickness of 68 mm, rotation of 9000 rpm, and sampling velocity of 108.3 cm/s. The experiment concluded that increased the thickness of porous media, face velocity, and porosity of porous media of RFD could increase the collection efficiency of porous media for sampling oil particles. Moreover, increased the rotation speed of RFD also increased the collection efficiency for sampling oil particles. Further investigation is required for those above operation parameters for RFD in this study in the future.

Keywords: oil aerosol, porous media filter, rotation, filtration

Procedia PDF Downloads 374
6340 Charting the Course: Using group Charters to Enhance Engagement and Learning Outcomes

Authors: Angela Knox

Abstract:

Student diversity in postgraduate classes puts major challengesoneducatorsseekingtoencouragestudentengagementand desired learning outcomes. This paper outlines the impact of a set of teaching initiatives aimed at addressing challenges associated with teaching and learning in an environment characterized by diversity in the student cohort. The study examines postgraduate students completing the core capstone unit within a specialized business degree. Although relatively small, the student cohort is highly diverse in terms of cultural backgrounds represented, prior learning and/or qualifications,aswellasdurationandtypeofworkexperiencerelevant to the degree being completed. The wide range of cultures, existing knowledge, and experience create enormous challenges with respect to students’ learning needs and outcomes. Subsequently, a suite of teaching innovations has been adopted to enhance curriculum content/delivery and the design of assessments. This paperexplores the impact of formalized group charters on students’ learning outcomes. Data from surveys and focus groups are used to assess the effectiveness of these practices. The results highlight the effectiveness of formalizedgroup charters in addressing diverse student needs and enhancing student engagement and learning outcomes. Thesefindings suggest that such practices would benefit students’ learning in environments marked by diversity in the student cohort. Specific recommendationsareofferedforothereducatorsworkingwithdiverse classes.

Keywords: assessment design, curriculum content, curriculum delivery, group charter, student diversity

Procedia PDF Downloads 113
6339 Utilization of Traditional Medicine for Treatment of Selected Illnesses among Crop-Farming Households in Edo State, Nigeria

Authors: Adegoke A. Adeyelu, Adeola T. Adeyelu, S. D. Y. Alfred, O. O. Fasina

Abstract:

This study examines the use of traditional medicines for the treatment of selected illnesses among crop-farming households in Edo State, Nigeria. A sample size of ninety (90) households were randomly selected for the study. Data were collected with a structured questionnaire alongside focus group discussions (FGD). Result shows that the mean age was 50 years old, the majority (76.7%) of the sampled farmers were below 60 years old. The majority (80.0%) of the farmers were married, about (92.2%) had formal education. It exposes that the majority of the respondents (76.7%) had household size of between 1-10 persons, about 55.6% had spent 11 years and above in crop farming. malaria (8th ), waist pains (7th ), farm injuries ( 6th ), cough (5th), acute headache(4th), skin infection (3rd), typhoid (2nd) and tuberculosis (1st ) were the most and least treated illness. Respondents (80%) had spent N10,000.00 ($27) and less on treatment of illnesses, 8.9% had spent N10,000.00-N20,000.0027 ($27-$55) 4.4% had spent between N20,100-N30,000.00 ($27-$83) while 6.7% had spent more than N30,100.00 ($83) on treatment of illnesses in the last one (1) year prior to the study. Age, years of farming, farm size, household size, level of income, cost of treatment, level of education, social network, and culture are some of the statistically significant factors influencing the utilization of traditional medicine. Farmers should be educated on methods of preventing illnesses, which is far cheaper than the curative.

Keywords: crop farming-households, selected illnesses, traditional medicines, Edo State

Procedia PDF Downloads 173
6338 Team Workforce Diversity and Team Outcomes: A Meta-Analytic Review

Authors: Hyeondal Jeong, Yoonjung Baek

Abstract:

This study was carried out a meta-analysis on team workforce diversity and team outcomes. Using data from 3,534 teams in 13 studies conducted in team-level settings, we examined whether contextual factors at research local and team-size, influenced team outcomes of team workforce diversity. This meta-analytic examines the team workforce diversity and team outcomes. 13 studies included in the analysis are studies published from 2009 to 2014. We first examined the correlations between all types of diversity and team performance, significant result (Fisher`s Z = .112, k = 32, 95% CI = 0.039 to 0.183). After the analysis was conducted to moderating effect of research local (Republic of Korea=1, other area=0) and team-size. As a result, research local moderating effect had a significant but team-size was not supported. Based on the above findings suggest implications and future research directions.

Keywords: team workforce diversity, team outcomes, meta- analytic, cross-cultural research

Procedia PDF Downloads 285