Search results for: work mode
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 15054

Search results for: work mode

11724 An Analytical Approach for the Fracture Characterization in Concrete under Fatigue Loading

Authors: Bineet Kumar

Abstract:

Many civil engineering infrastructures frequently encounter repetitive loading during their service life. Due to the inherent complexity observed in concrete, like quasi-brittle materials, understanding the fatigue behavior in concrete still posesa challenge. Moreover, the fracture process zone characteristics ahead of the crack tip have been observed to be different in fatigue loading than in the monotonic cases. Therefore, it is crucial to comprehend the energy dissipation associated with the fracture process zone (FPZ) due to repetitive loading. It is well known that stiffness degradation due to cyclic loadingprovides a better understanding of the fracture behavior of concrete. Under repetitive load cycles, concrete members exhibit a two-stage stiffness degradation process. Experimentally it has been observed that the stiffness decreases initially with an increase in crack length and subsequently increases. In this work, an attempt has been made to propose an analytical expression to predict energy dissipation and later the stiffness degradation as a function of crack length. Three-point bend specimens have been considered in the present work to derive the formulations. In this approach, the expression for the resultant stress distribution below the neutral axis has been derived by correlating the bending stress with the cohesive stresses developed ahead of the crack tip due to the existence of the fracture process zone. This resultant stress expression is utilized to estimate the dissipated energydue to crack propagation as a function of crack length. Further, the formulation for the stiffness degradation has been developed by relating the dissipated energy with the work done. It can be used to predict the critical crack length and fatigue life. An attempt has been made to understand the influence of stress amplitude on the damage pattern by using the information on the rate of stiffness degradation. It has been demonstrated that with the increase in the stress amplitude, the damage/FPZ proceeds more in the direction of crack propagation compared to the damage in the direction parallel to the span of the beam, which causes a lesser rate of stiffness degradation for the incremental crack length. Further, the effect of loading frequency has been investigated in terms of stiffness degradation. Under low-frequency loading cases, the damage/FPZ has been found to spread more in the direction parallel to the span, in turn reducing the critical crack length and fatigue life. In such a case, a higher rate of stiffness degradation has been observed in comparison to the high-frequency loading case.

Keywords: fatigue life, fatigue, fracture, concrete

Procedia PDF Downloads 82
11723 Comparison of Wake Oscillator Models to Predict Vortex-Induced Vibration of Tall Chimneys

Authors: Saba Rahman, Arvind K. Jain, S. D. Bharti, T. K. Datta

Abstract:

The present study compares the semi-empirical wake-oscillator models that are used to predict vortex-induced vibration of structures. These models include those proposed by Facchinetti, Farshidian, and Dolatabadi, and Skop and Griffin. These models combine a wake oscillator model resembling the Van der Pol oscillator model and a single degree of freedom oscillation model. In order to use these models for estimating the top displacement of chimneys, the first mode vibration of the chimneys is only considered. The modal equation of the chimney constitutes the single degree of freedom model (SDOF). The equations of the wake oscillator model and the SDOF are simultaneously solved using an iterative procedure. The empirical parameters used in the wake-oscillator models are estimated using a newly developed approach, and response is compared with experimental data, which appeared comparable. For carrying out the iterative solution, the ode solver of MATLAB is used. To carry out the comparative study, a tall concrete chimney of height 210m has been chosen with the base diameter as 28m, top diameter as 20m, and thickness as 0.3m. The responses of the chimney are also determined using the linear model proposed by E. Simiu and the deterministic model given in Eurocode. It is observed from the comparative study that the responses predicted by the Facchinetti model and the model proposed by Skop and Griffin are nearly the same, while the model proposed by Fashidian and Dolatabadi predicts a higher response. The linear model without considering the aero-elastic phenomenon provides a less response as compared to the non-linear models. Further, for large damping, the prediction of the response by the Euro code is relatively well compared to those of non-linear models.

Keywords: chimney, deterministic model, van der pol, vortex-induced vibration

Procedia PDF Downloads 208
11722 Rheology and Structural Arrest of Dense Dairy Suspensions: A Soft Matter Approach

Authors: Marjan Javanmard

Abstract:

The rheological properties of dairy products critically depend on the underlying organisation of proteins at multiple length scales. When heated and acidified, milk proteins form particle gel that is viscoelastic, solvent rich, ‘soft’ material. In this work recent developments on the rheology of soft particles suspensions were used to interpret and potentially define the properties of dairy gel structures. It is discovered that at volume fractions below random close packing (RCP), the Maron-Pierce-Quemada (MPQ) model accurately predicts the viscosity of the dairy gel suspensions without fitting parameters; the MPQ model has been shown previously to provide reasonable predictions of the viscosity of hard sphere suspensions from the volume fraction, solvent viscosity and RCP. This surprising finding demonstrates that up to RCP, the dairy gel system behaves as a hard sphere suspension and that the structural aggregates behave as discrete particulates akin to what is observed for microgel suspensions. At effective phase volumes well above RCP, the system is a soft solid. In this region, it is discovered that the storage modulus of the sheared AMG scales with the storage modulus of the set gel. The storage modulus in this regime is reasonably well described as a function of effective phase volume by the Evans and Lips model. Findings of this work has potential to aid in rational design and control of dairy food structure-properties.

Keywords: dairy suspensions, rheology-structure, Maron-Pierce-Quemada Model, Evans and Lips Model

Procedia PDF Downloads 207
11721 The Factors for Developing Trainers in Auto Parts Manufacturing Factories at Amata Nakon Industrial Estate in Cholburi Province

Authors: Weerakarj Dokchan

Abstract:

The purposes of this research are to find out the factors for developing trainers in the auto part manufacturing factories (AMF) in Amata Nakon Industrial Estate Cholburi. Population in this study included 148 operators to complete the questionnaires and 10 trainers to provide the information on the interview. The research statistics consisted of percentage, mean, standard deviation and step-wise multiple linear regression analysis.The analysis of the training model revealed that: The research result showed that the development factors of trainers in AMF consisted of 3 main factors and 8 sub-factors: 1) knowledge competency consisting of 4 sub-factors; arrangement of critical thinking, organizational loyalty, working experience of the trainers, analysis of behavior, and work and organization loyalty which could predict the success of the trainers at 55.60%. 2) Skill competency consisted of 4 sub-factors, arrangement of critical thinking, organizational loyalty and analysis of behavior and work and the development of emotional quotient. These 4 sub-factors could predict the success of the trainers in skill aspect 55.90%. 3) The attitude competency consisted of 4 sub-factors, arrangement of critical thinking, intention of trainee computer competency and teaching psychology. In conclusion, these 4 sub-factors could predict the success of the trainers in attitude aspect 58.50%.

Keywords: the development factors, trainers development, trainer competencies, auto part manufacturing factory (AMF), AmataNakon Industrial Estate Cholburi

Procedia PDF Downloads 290
11720 The Publishing Process and Results of the Chinese Annotated Edition of John Dewey’s “Experience and Education: The 60th Anniversary Edition”

Authors: Wen-jing Shan

Abstract:

The Chinese annotated edition of “Experience and education: The 60th anniversary edition,” originally written in English by John Dewey (1859-1952), was published in 2015 by this author. A report of the process and results of the translation and annotation of the book is the purpose of this paper. It is worth mentioning that the original 1938 edition was considered as the best concise statement on education by John Dewey, one the most important educational theorists of the twentieth century. One of the features of this The 60th anniversary edition is that the original publisher, Kappa Delta Pi International Honor Society, invited four contemporary Deweyan scholars who had been awarded the Society’s Laureate Scholar to write a review of the book published by Dewey, who was the first to receive this honor. The four scholars are Maxine Greene(1917-2014), Philip W. Jackson(1928-2015), Linda Darling-Hammond(1951-), and O. L. Davis, Jr.(1928-). The original 1938 edition, the best concise statement on education by the most important educational theorist of the twentieth century, was translated into Chinese for five times after its publication in the U.S.A, three in the 1940s, one in the 1990s, and one in 2010s. Nonetheless, the five translations have few or no annotations and have some flaws of mis-interpretations and lack of information. The author retranslated and annotated the book to make the interpretations more faithful, expressive, and elegant, and providing the readers with more understanding and more correct information. This author started the project of translation and annotation sponsored by Taiwan Ministry of Science and Technology in August 2011 and finished and published by July 2015. The work, the author, did was divided into three stages. First, in the preparatory stage of the project, the summary of each chapter, the rationale of the book, the textual commentary, the development of the original and Chinese editions, and reviews and criticisms, as well as Dewey’s biography and bibliography were initially investigated. Secondly, on the basis of the above preliminary work, the translation with annotation of Experience and Education, an epitome of Dewey’s biography and bibliography, a chronology, and a critical introduction for the Experience and Education were written. In the critical introduction, Dewey’s philosophy of experience and educational ideas will be examined along the timeline of human thought. And the vast literature about Dewey and his work will be instrumental to reveal the historical significance of Experience and Education on the modern age and make the critical introduction more knowledgeable. Third, the final stage took another two years to review and revise the draft of the work and send it for publication. There are two parts in the book. The first part is a scholarly introduction including Dewey’s chronicle (in short form), Dewey’s mind, people and life, the importance of “Experience and education”, the necessity of re-translation and re-annotation of “Experience and education” into Chinese. The second part is the re-translation and re-annotation version, including Dewey’s “Experience and education” and four papers written by contemporary scholars.

Keywords: John Dewey, experience and education: the 60th anniversary edition, translation, annotation

Procedia PDF Downloads 145
11719 Research on Construction of Subject Knowledge Base Based on Literature Knowledge Extraction

Authors: Yumeng Ma, Fang Wang, Jinxia Huang

Abstract:

Researchers put forward higher requirements for efficient acquisition and utilization of domain knowledge in the big data era. As literature is an effective way for researchers to quickly and accurately understand the research situation in their field, the knowledge discovery based on literature has become a new research method. As a tool to organize and manage knowledge in a specific domain, the subject knowledge base can be used to mine and present the knowledge behind the literature to meet the users' personalized needs. This study designs the construction route of the subject knowledge base for specific research problems. Information extraction method based on knowledge engineering is adopted. Firstly, the subject knowledge model is built through the abstraction of the research elements. Then under the guidance of the knowledge model, extraction rules of knowledge points are compiled to analyze, extract and correlate entities, relations, and attributes in literature. Finally, a database platform based on this structured knowledge is developed that can provide a variety of services such as knowledge retrieval, knowledge browsing, knowledge q&a, and visualization correlation. Taking the construction practices in the field of activating blood circulation and removing stasis as an example, this study analyzes how to construct subject knowledge base based on literature knowledge extraction. As the system functional test shows, this subject knowledge base can realize the expected service scenarios such as a quick query of knowledge, related discovery of knowledge and literature, knowledge organization. As this study enables subject knowledge base to help researchers locate and acquire deep domain knowledge quickly and accurately, it provides a transformation mode of knowledge resource construction and personalized precision knowledge services in the data-intensive research environment.

Keywords: knowledge model, literature knowledge extraction, precision knowledge services, subject knowledge base

Procedia PDF Downloads 153
11718 South Africa’s Post-Apartheid Film Narratives of HIV/AIDS: A Case of ‘Yesterday’

Authors: Moyahabo Molefe

Abstract:

The persistence of HIV/AIDS infection rates in SA has not only been a subject of academic debate but a mediated narrative that has dominated SA’s post-apartheid film space over the last two decades. SA’s colonial geo-spatial architecture still influences migrant labour patterns, which the Oscar-nominated (2003) SA film ‘Yesterday’ has erstwhile reflected upon, yet continues to account for the spread of HIV/AIDS in SA society. Accordingly, men who had left their homes in the rural areas to work in the mines in the cities become infected with HIV/AIDS, only to return home to infect their wives or partners in the rural areas. This paper analyses, through Social Semiotic theory, how SA geo-spatial arrangement had raptured family structures with both men and women taking new residences in the urban areas where they work away from their homes. By using Social semiotic theory, this paper seeks to understand how images and discourses have been deployed in the film ‘Yesterday’ to demonstrate how HIV/AIDS is embedded in the socio-cultural, economic and political architect of SA society. The study uses qualitative approach and content/text/visual semiotic analysis to decipher meanings from array of imagery and discourses/dialogues that are used to mythologise the relationship between the spread of HIV/AIDS and SA migrant labour patterns. The findings of the study are significant to propose a conceptual framework that can be used to mitigate the spread of HIV/AIDS among SA populace, against the backdrop of changing migrant labour patterns and other related factors

Keywords: colonialism, decoloniality, HIV/AIDS, labour migration patterns, social semiotics

Procedia PDF Downloads 58
11717 Development of a Novel Nanobiosystem for the Selective Nanophotothermolysis of Meticilin Resistant Staphyloccocous Aureus Using Anti-MRSA Antibody Functionalized Gold Nanoparticles

Authors: Lucian Mocan, Cristian Matea, Flaviu A. Tabaran, Teodora Mocan, Cornel Iancu

Abstract:

Introduction: Due to antibiotic resistance, systemic infections caused by Meticilin resistant Staphyloccocous Aureus (MRSA) are the main cause of millions of deaths each year. Development of new active biomolecules that are highly effective and refractory to antibiotic resistance may open new avenues in the field of antimicrobial therapy. In this research, we have focused on the development of a novel nanobiosystem with high affinity for MRSA microorganism to mediate its selective laser thermal ablation. Materials and Methods: Gold nanoparticles (15nm in diameter) linked to a specific antibody against MRSA surface were selectively delivered (at various concentrations and incubation times) and internalized into MRSA microorganism following the treatment these multidrug-resistant bacteria were irradiated using a 2w, 808 nm LASER. Results and Discussions: The post-irradiation necrotic rate ranged from 51.2% (for 1 mg/L) to 87.3% (for 50 mg/L) at 60 seconds (p<0.001), while at 30 minute the necrotic rate increased from 64.3% (1 mg/L) to 92.1% (50 mg/L), p value<0.001. Significantly lower apoptotic rates were obtained in irradiated MRSA treated with GNPs only (control) treated for 60 seconds and 30 minutes at concentrations ranging from 1 mg/L to 50 mg/L. We show here that the optimal LASER mediated the necrotic effect of MRSA after incubation with anti-MRSA-Ab was obtained at a concentration of 50 mg/L. Conclusion: In the presented research, we obtained a very efficacious pulse laser mode treatment of individual MRSA agents with minimal effects on the surrounding medium, providing highly localized destruction only for MRSA microorganism.

Keywords: MRSA, photothermolysis, antibiotic resistance, gold nanoparticles

Procedia PDF Downloads 419
11716 Applying Serious Game Design Frameworks to Existing Games for Integration of Custom Learning Objectives

Authors: Jonathan D. Moore, Mark G. Reith, David S. Long

Abstract:

Serious games (SGs) have been shown to be an effective teaching tool in many contexts. Because of the success of SGs, several design frameworks have been created to expedite the process of making original serious games to teach specific learning objectives (LOs). Even with these frameworks, the time required to create a custom SG from conception to implementation can range from months to years. Furthermore, it is even more difficult to design a game framework that allows an instructor to create customized game variants supporting multiple LOs within the same field. This paper proposes a refactoring methodology to apply the theoretical principles from well-established design frameworks to a pre-existing serious game. The expected result is a generalized game that can be quickly customized to teach LOs not originally targeted by the game. This methodology begins by describing the general components in a game, then uses a combination of two SG design frameworks to extract the teaching elements present in the game. The identified teaching elements are then used as the theoretical basis to determine the range of LOs that can be taught by the game. This paper evaluates the proposed methodology by presenting a case study of refactoring the serious game Battlespace Next (BSN) to teach joint military capabilities. The range of LOs that can be taught by the generalized BSN are identified, and examples of creating custom LOs are given. Survey results from users of the generalized game are also provided. Lastly, the expected impact of this work is discussed and a road map for future work and evaluation is presented.

Keywords: serious games, learning objectives, game design, learning theory, game framework

Procedia PDF Downloads 102
11715 Geographical Parthenogenesis in Plants

Authors: Elvira Hörandl

Abstract:

The term “Geographical parthenogenesis” describes the phenomenon that asexual organisms usually occupy larger and more northern distribution areas than their sexual relatives and tend to colonize previously glaciated areas. Several case studies in flowering plants confirm the geographical pattern, but the causal factors behind the phenomenon are still unclear. Previous authors regarded predominant polyploidy in asexual (apomictic) plants as the main factor. However, the geographical pattern is not the rule for sexual polyploids. Recent research confirmed a previous hypothesis of the author that a combination of factors is acting: Although uniparental reproduction provides better colonization abilities, it is most efficient in combination with polyploidy. I will present results on case studies in the genus Ranunculus of both autopolyploid and allopolyploid species and species complexes reproducing via facultative apomixis. Polyploidy seems to contribute mainly to a better tolerance of colder climates and temperate extremes, whereby epigenetic flexibility, changes in gene expression, and phenotypic plasticity play an important role in occupying ecological niches under harsh conditions. Phylogenomic studies entangle complex hybrid origins of asexual taxa, which increases intragenomic heterozygosity of asexual plants. Interestingly, our results suggest an association of sexuality with abiotic stresses, specifically with light stress, which might explain that still, most plants in high altitudes and in southern areas retain sexual reproduction despite other climatic conditions that would favor apomictic plants. We conclude that geographical parthenogenesis results from the complex interplay of the genomic constitution, mode of reproduction and environmental factors.

Keywords: apomixis, polyploidy, hybridization, abiotic stress, epigenetics, phylogenomics

Procedia PDF Downloads 57
11714 Assessing the Gap between the Policies and Existing Living Conditions of Migrant Construction Workers: A Case Study of Vijayawada

Authors: Ayushi Mishra

Abstract:

Migrant construction workers or construction labors are one of the majority of the working population in our urban and rural areas. Even after being the majority, their involvement in the upbringing of the economy is hardly ever documented or recognized. Non-permanent or migrant workers face loads of exploitations and susceptibilities than other informal sector workers in India which in turn has affected the productivity of the labors. The relation of their employment and migration and the links of these dynamics to their housing and other basic needs in the city are mostly unstated. Even the urban planning and housing policies do not make thoughtful provision for them, they forcing them to live in extremely wretched conditions. And even if the policies are made, it frequently happens that they are not implemented. As the issue is very much prevalent in today’s time in India with so many large-scale and labor extensive projects going on, this study focuses on the assessment of the gap between the existing government policies and the current scenario of the construction workers in ongoing projects of Vijayawada, Andhra Pradesh. A few of the policies for construction workers conditions a lot of things, out of which only a few are functional which makes this study to assess the reason behind the unorganized living condition and poor physical, the social and mental health of construction workers of Vijayawada. In present, the dignity of construction labors is compromised every day on construction sites, in terms of work and basic rights which leads to many other problems in future. So to work for the betterment of this community, knowledge on the differences is very much required and hence this study is a little effort to replenish the difference and compare the policies with the existing conditions of construction labors in Vijayawada.

Keywords: construction, labours, policy, productivity

Procedia PDF Downloads 313
11713 Cantilever Secant Pile Constructed in Sand: Numerical Comparative Study and Design Aids – Part II

Authors: Khaled R. Khater

Abstract:

All civil engineering projects include excavation work and therefore need some retaining structures. Cantilever secant pile walls are an economical supporting system up to 5.0-m depths. The parameters controlling wall tip displacement are the focus of this paper. So, two analysis techniques have been investigated and arbitrated. They are the conventional method and finite element analysis. Accordingly, two computer programs have been used, Excel sheet and Plaxis-2D. Two soil models have been used throughout this study. They are Mohr-Coulomb soil model and Isotropic Hardening soil models. During this study, two soil densities have been considered, i.e. loose and dense sand. Ten wall rigidities have been analyzed covering ranges of perfectly flexible to completely rigid walls. Three excavation depths, i.e. 3.0-m, 4.0-m and 5.0-m were tested to cover the practical range of secant piles. This work submits beneficial hints about secant piles to assist designers and specification committees. Also, finite element analysis, isotropic hardening, is recommended to be the fair judge when two designs conflict. A rational procedure using empirical equations has been suggested to upgrade the conventional method to predict wall tip displacement ‘δ’. Also, a reasonable limitation of ‘δ’ as a function of excavation depth, ‘h’ has been suggested. Also, it has been found that, after a certain penetration depth any further increase of it does not positively affect the wall tip displacement, i.e. over design and uneconomic.

Keywords: design aids, numerical analysis, secant pile, Wall tip displacement

Procedia PDF Downloads 177
11712 Breast Cancer as a Response to Distress in Women with or without a History of Precancerous Breast Disease

Authors: Viacheslav Sushko, Viktor Sushko

Abstract:

Pre-cancerous breast diseases are pathological changes that precede the appearance of adenocarcinoma. The most common benign breast disease is mastopathy. We examined the life and disease history of 114 women aged 58-69 who were diagnosed with adenocarcinoma of the breast at different stages of development. They filled out the Reeder Scale to determine the level of stress. The results of the study revealed that 62 of them had mastopathy at the age of 30-45 years old. These women refused surgical treatment for mastopathy. Five to six years before their diagnosis of adenocarcinoma of the mammary gland, 84 women had experienced severe stress (death of a beloved close relative, torture accompanied by rape, prolonged stay in extreme conditions (under bombardment and bombardment). In the assessment of data from completed Reeder scales, 114 women had a high level of mental stress, with a score from 1-1.72. The 84 women who suffered from severe stress showed overeating or a significant decrease in food intake, insomnia, apathy, increased irritability and restlessness, loss of interest in sexual relationships, forgetfulness, difficulty in performing routine work, prolonged uncontrollable headaches, unexplained fatigue, heart pain, reduced capacity for work. In conclusion, it is important to provide psychotherapy for breast cancer patients as the diagnosis, and the different stages of treatment are very stressful. It is also advisable to see a psychiatrist at an early stage and prevent distress and treat precancerous breast disease.

Keywords: breast cancer, distress, mastopathy, severe stress

Procedia PDF Downloads 119
11711 Injection Practices among Private Medical Practitioners of Karachi Pakistan

Authors: Mohammad Tahir Yousafzai, Nighat Nisar, Rehana Khalil

Abstract:

The aim of this study is to assess the practices of sharp injuries and factors leading to it among medical practitioners in slum areas of Karachi, Pakistan. A cross sectional study was conducted in slum areas of Landhi Town Karachi. All medical practitioners (317) running the private clinics in the areas were asked to participate in the study. Data was collected on self administered pre-tested structured questionnaires. The frequency with percentage and 95% confidence interval was calculated for at least one sharp injury (SI) in the last one year. The factors leading to sharp injuries were assessed using multiple logistic regressions. About 80% of private medical practitioners consented to participate. Among these 87% were males and 13% were female. The mean age was 38±11 years and mean work experience was 12±9 years. The frequency of at least one sharp injury in the last one year was 27%(95% CI: 22.2-32). Almost 47% of Sharp Injuries were caused by needle recapping, less work experience, less than 14 years of schooling, more than 20 patients per day, administering more than 30 injections per day, reuse of syringes and needle recapping after use were significantly associated with sharp injuries. Injection practices were found inadequate among private medical practitioners in slum areas of Karachi, and the frequency of Sharp Injuries was found high in these areas. There is a risk of occupational transmission of blood borne infections among medical practitioners warranting an urgent need for launching awareness and training on standard precautions for private medical practitioners in the slum areas of Karachi.

Keywords: injection practices, private practitioners, sharp injuries, blood borne infections

Procedia PDF Downloads 404
11710 Structural and Magnetic Properties of CoFe2O4:Nd3+/Dy3+/Pr3+/Gd3+ Nanoparticles Synthesized by Starch-Assisted Sol-Gel Auto-Combustion Method and Annealing Effect

Authors: Raghvendra Singh Yadav, Ivo Kuřitka, Jaromir Havlica, Zuzana Kozakova, Jiri Masilko, Lukas Kalina, Miroslava Hajdúchová, Vojtěch Enev, Jaromir Wasserbauer

Abstract:

In this work, we investigated the structural and magnetic properties of CoFe2O4:Nd3+/Dy3+/Pr3+/Gd3+ nanoparticles synthesized by starch-assisted sol-gel combustion method. X-ray diffraction pattern confirmed the formation of cubic spinel structure of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) doped CoFe2O4 spinel ferrite nanoparticles. Raman and Fourier Transform Infrared spectroscopy study also confirmed cubic spinel structure of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles. The field emission scanning electron microscopy study revealed the effect of annealing temperature on size of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles and particles were in the range of 10-100 nm. The magnetic properties of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles were investigated by using vibrating sample magnetometer. The variation in saturation magnetization, coercivity and remanent magnetization with annealing temperature/ particle size of rare-earth ions (Nd3+, Dy3+, Pr3+, Gd3+) substituted CoFe2O4 nanoparticles was observed. Acknowledgment: This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic – Program NPU I (LO1504).

Keywords: starch, sol-gel combustion method, rare-earth ions, spinel ferrite nanoparticles, magnetic properties

Procedia PDF Downloads 340
11709 Integration of Virtual Learning of Induction Machines for Undergraduates

Authors: Rajesh Kumar, Puneet Aggarwal

Abstract:

In context of understanding problems faced by undergraduate students while carrying out laboratory experiments dealing with high voltages, it was found that most of the students are hesitant to work directly on machine. The reason is that error in the circuitry might lead to deterioration of machine and laboratory instruments. So, it has become inevitable to include modern pedagogic techniques for undergraduate students, which would help them to first carry out experiment in virtual system and then to work on live circuit. Further advantages include that students can try out their intuitive ideas and perform in virtual environment, hence leading to new research and innovations. In this paper, virtual environment used is of MATLAB/Simulink for three-phase induction machines. The performance analysis of three-phase induction machine is carried out using virtual environment which includes Direct Current (DC) Test, No-Load Test, and Block Rotor Test along with speed torque characteristics for different rotor resistances and input voltage, respectively. Further, this paper carries out computer aided teaching of basic Voltage Source Inverter (VSI) drive circuitry. Hence, this paper gave undergraduates a clearer view of experiments performed on virtual machine (No-Load test, Block Rotor test and DC test, respectively). After successful implementation of basic tests, VSI circuitry is implemented, and related harmonic distortion (THD) and Fast Fourier Transform (FFT) of current and voltage waveform are studied.

Keywords: block rotor test, DC test, no load test, virtual environment, voltage source inverter

Procedia PDF Downloads 339
11708 Speech Detection Model Based on Deep Neural Networks Classifier for Speech Emotions Recognition

Authors: A. Shoiynbek, K. Kozhakhmet, P. Menezes, D. Kuanyshbay, D. Bayazitov

Abstract:

Speech emotion recognition has received increasing research interest all through current years. There was used emotional speech that was collected under controlled conditions in most research work. Actors imitating and artificially producing emotions in front of a microphone noted those records. There are four issues related to that approach, namely, (1) emotions are not natural, and it means that machines are learning to recognize fake emotions. (2) Emotions are very limited by quantity and poor in their variety of speaking. (3) There is language dependency on SER. (4) Consequently, each time when researchers want to start work with SER, they need to find a good emotional database on their language. In this paper, we propose the approach to create an automatic tool for speech emotion extraction based on facial emotion recognition and describe the sequence of actions of the proposed approach. One of the first objectives of the sequence of actions is a speech detection issue. The paper gives a detailed description of the speech detection model based on a fully connected deep neural network for Kazakh and Russian languages. Despite the high results in speech detection for Kazakh and Russian, the described process is suitable for any language. To illustrate the working capacity of the developed model, we have performed an analysis of speech detection and extraction from real tasks.

Keywords: deep neural networks, speech detection, speech emotion recognition, Mel-frequency cepstrum coefficients, collecting speech emotion corpus, collecting speech emotion dataset, Kazakh speech dataset

Procedia PDF Downloads 85
11707 Mixotrophic Growth as a Tool for Increasing Polyhydroxyalkanoates (PHA) Production in Cyanobacteria

Authors: Zuzana Sedrlova, Eva Slaninova, Ines Fritz, Christina Daffert, Stanislav Obruca

Abstract:

Cyanobacteria are ecologically extremely important phototrophic gram-negative bacteria capable of oxygenic photosynthesis. They synthesize many interesting metabolites such as glycogen, carotenoids, but the most interesting metabolites are polyhydroxyalkanoates (PHA). The main advantage of cyanobacteria is the fact they do not require costly organic substrate and, oppositely, cyanobacteria can fix CO₂. PHA serves primarily as a carbon and energy source and occurs in the form of intracellular granules in bacterial cells. It is possible, PHA helps cyanobacteria to survive stress conditions since increased PHA synthesis was observed during cultivation in stress conditions. PHA is microbial biopolymers that are biodegradable with similar properties as petrochemical synthetic plastics. Production of PHA by heterotrophic bacteria is expensive; for price reduction waste materials as input, materials are used. Positively, cyanobacteria principally do not require organic carbon substrate since they are capable of CO₂ fixation. In this work, we demonstrated that stress conditions lead to the highest obtained yields of PHA in cyanobacterial cultures. Two cyanobacterial cultures from genera Synechocystis were used in this work. Cultivations were performed either in Erlenmayer flask or in tube multicultivator. Multiple stressors were applied on cyanobacterial cultures, and stressors include PHA precursors. PHA precursors are chemical substances and some of them do not occur naturally in the environment. Cultivation with the same PHA precursors in the same concentration led to a 1,6x higher amount of PHA when a multicultivator was used. The highest amount of PHA reached 25 % of PHA in dry cyanobacterial biomass. Both strains are capable of co-polymer synthesis in the presence of their structural precursor. The composition of co-polymer differs in Synechocystis sp. PCC 6803 and Synechocystis salina CCALA 192. Synechocystis sp. PCC 6803 cultivated with γ-butyrolakton accumulated co-polymer of 3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB) the composition of the copolymer was 56 % of 4HB and 44 % of 3HB. The total amount of PHA, as well as yield of biomass, was lower than in control due to the toxic properties of γ-butyrolakton. Funding: This study was partly funded by the project GA19- 19-29651L of the Czech Science Foundation (GACR) and partly funded by the Austrian Science Fund (FWF), a project I 4082-B25. This work was supported by Brno, Ph.D. Talent – Funded by the Brno City Municipality.

Keywords: co-polymer, cyanobacteria, PHA, synechocystis

Procedia PDF Downloads 187
11706 Augmented Reality Enhanced Order Picking: The Potential for Gamification

Authors: Stavros T. Ponis, George D. Plakas-Koumadorakis, Sotiris P. Gayialis

Abstract:

Augmented Reality (AR) can be defined as a technology, which takes the capabilities of computer-generated display, sound, text and effects to enhance the user's real-world experience by overlaying virtual objects into the real world. By doing that, AR is capable of providing a vast array of work support tools, which can significantly increase employee productivity, enhance existing job training programs by making them more realistic and in some cases introduce completely new forms of work and task executions. One of the most promising AR industrial applications, as literature shows, is the use of Head Worn, monocular or binocular Displays (HWD) to support logistics and production operations, such as order picking, part assembly and maintenance. This paper presents the initial results of an ongoing research project for the introduction of a dedicated AR-HWD solution to the picking process of a Distribution Center (DC) in Greece operated by a large Telecommunication Service Provider (TSP). In that context, the proposed research aims to determine whether gamification elements should be integrated in the functional requirements of the AR solution, such as providing points for reaching objectives and creating leaderboards and awards (e.g. badges) for general achievements. Up to now, there is a an ambiguity on the impact of gamification in logistics operations since gamification literature mostly focuses on non-industrial organizational contexts such as education and customer/citizen facing applications, such as tourism and health. To the contrary, the gamification efforts described in this study focus in one of the most labor- intensive and workflow dependent logistics processes, i.e. Customer Order Picking (COP). Although introducing AR in COP, undoubtedly, creates significant opportunities for workload reduction and increased process performance the added value of gamification is far from certain. This paper aims to provide insights on the suitability and usefulness of AR-enhanced gamification in the hard and very demanding environment of a logistics center. In doing so, it will utilize a review of the current state-of-the art regarding gamification of production and logistics processes coupled with the results of questionnaire guided interviews with industry experts, i.e. logisticians, warehouse workers (pickers) and AR software developers. The findings of the proposed research aim to contribute towards a better understanding of AR-enhanced gamification, the organizational change it entails and the consequences it potentially has for all implicated entities in the often highly standardized and structured work required in the logistics setting. The interpretation of these findings will support the decision of logisticians regarding the introduction of gamification in their logistics processes by providing them useful insights and guidelines originating from a real life case study of a large DC operating more than 300 retail outlets in Greece.

Keywords: augmented reality, technology acceptance, warehouse management, vision picking, new forms of work, gamification

Procedia PDF Downloads 138
11705 A Three-Dimensional TLM Simulation Method for Thermal Effect in PV-Solar Cells

Authors: R. Hocine, A. Boudjemai, A. Amrani, K. Belkacemi

Abstract:

Temperature rising is a negative factor in almost all systems. It could cause by self heating or ambient temperature. In solar photovoltaic cells this temperature rising affects on the behavior of cells. The ability of a PV module to withstand the effects of periodic hot-spot heating that occurs when cells are operated under reverse biased conditions is closely related to the properties of the cell semi-conductor material. In addition, the thermal effect also influences the estimation of the maximum power point (MPP) and electrical parameters for the PV modules, such as maximum output power, maximum conversion efficiency, internal efficiency, reliability, and lifetime. The cells junction temperature is a critical parameter that significantly affects the electrical characteristics of PV modules. For practical applications of PV modules, it is very important to accurately estimate the junction temperature of PV modules and analyze the thermal characteristics of the PV modules. Once the temperature variation is taken into account, we can then acquire a more accurate MPP for the PV modules, and the maximum utilization efficiency of the PV modules can also be further achieved. In this paper, the three-Dimensional Transmission Line Matrix (3D-TLM) method was used to map the surface temperature distribution of solar cells while in the reverse bias mode. It was observed that some cells exhibited an inhomogeneity of the surface temperature resulting in localized heating (hot-spot). This hot-spot heating causes irreversible destruction of the solar cell structure. Hot spots can have a deleterious impact on the total solar modules if individual solar cells are heated. So, the results show clearly that the solar cells are capable of self-generating considerable amounts of heat that should be dissipated very quickly to increase PV module's lifetime.

Keywords: thermal effect, conduction, heat dissipation, thermal conductivity, solar cell, PV module, nodes, 3D-TLM

Procedia PDF Downloads 376
11704 Review on Crew Scheduling of Bus Transit: A Case Study in Kolkata

Authors: Sapan Tiwari, Namrata Ghosh

Abstract:

In urban mass transit, crew scheduling always plays a significant role. It deals with the formulation of work timetables for its staff so that an organization can meet the demand for its products or services. The efficient schedules of a specified timetable have an enormous impact on staff demand. It implies that an urban mass transit company's financial outcomes are strongly associated with planning operations in the region. The research aims to demonstrate the state of the crew scheduling studies and its practical implementation in mass transit businesses in metropolitan areas. First, there is a short overview of past studies in the field. Subsequently, the restrictions and problems with crew scheduling and some models, which have been developed to solve the related issues with their mathematical formulation, are defined. The comments are completed by a description of the solution opportunities provided by computer-aided scheduling program systems for operational use and exposures from urban mass transit organizations. Furthermore, Bus scheduling is performed using the Hungarian technique of problem-solving tasks and mathematical modeling. Afterward, the crew scheduling problem, which consists of developing duties using predefined tasks with set start and end times and places, is resolved. Each duty has to comply with a set line of work. The objective is to minimize a mixture of fixed expenses (number of duties) and varying costs. After the optimization of cost, the outcome of the research is that the same frequency can be provided with fewer buses and less workforce.

Keywords: crew scheduling, duty, optimization of cost, urban mass transit

Procedia PDF Downloads 138
11703 Investigating Al₂O₃ Nanofluid Based on Seawater and Effluent Water Mix for Water Injection Application; Sandstone

Authors: Meshal Al-Samhan, Abdullah Al-Marshed

Abstract:

Recently, there has been a tremendous increase in interest in nanotechnology applications and nanomaterials in the oilfield. In the last decade, the global increase in oil production resulted in large amounts of produced water, causing a significant problem for all producing countries and companies. This produced water deserves special attention and a study of its characteristics to understand and determine how it can be treated and later used for suitable applications such as water injection for Enhance Oil Recovery (EOR) without harming the environment. This work aims to investigate the prepared compatible mixed water (seawater and effluent water) response to nanoparticles for EOR water injection. The evaluation of different mix seawater/effluent water ratios (60/40,70/30) for their characteristics prior to nanofluid preparation using Inductive Couple Plasma (ICP) analysis, potential zeta test, and OLI software (the OLI Systems is a recognised leader in aqueous chemistry). This step of the work revealed the suitability of the water mix with a lower effluent-water ratio. Also, OLI predicted that the 60:40 mix needs to be balanced around temperatures of 70 ºC to avoid the mass accumulation of calcium sulfate and strontium sulfate. Later the prepared nanofluid was tested for interfacial tension (IFT) and wettability restoration in the sandstone rock; the Al2O3 nanofluid at 0.06 wt% concentration reduced the IFT by more than 16% with moderate water wet contact angle. The study concluded that the selected nanoparticle Al2O3 had demonstrated excellent performance in decreasing the interfacial tension with respect to the selected water mix type (60/40) at low nanoparticles wt%.

Keywords: nano AL2O3, sanstone, nanofluid, IFT, wettability

Procedia PDF Downloads 84
11702 Signs, Signals and Syndromes: Algorithmic Surveillance and Global Health Security in the 21st Century

Authors: Stephen L. Roberts

Abstract:

This article offers a critical analysis of the rise of syndromic surveillance systems for the advanced detection of pandemic threats within contemporary global health security frameworks. The article traces the iterative evolution and ascendancy of three such novel syndromic surveillance systems for the strengthening of health security initiatives over the past two decades: 1) The Program for Monitoring Emerging Diseases (ProMED-mail); 2) The Global Public Health Intelligence Network (GPHIN); and 3) HealthMap. This article demonstrates how each newly introduced syndromic surveillance system has become increasingly oriented towards the integration of digital algorithms into core surveillance capacities to continually harness and forecast upon infinitely generating sets of digital, open-source data, potentially indicative of forthcoming pandemic threats. This article argues that the increased centrality of the algorithm within these next-generation syndromic surveillance systems produces a new and distinct form of infectious disease surveillance for the governing of emergent pathogenic contingencies. Conceptually, the article also shows how the rise of this algorithmic mode of infectious disease surveillance produces divergences in the governmental rationalities of global health security, leading to the rise of an algorithmic governmentality within contemporary contexts of Big Data and these surveillance systems. Empirically, this article demonstrates how this new form of algorithmic infectious disease surveillance has been rapidly integrated into diplomatic, legal, and political frameworks to strengthen the practice of global health security – producing subtle, yet distinct shifts in the outbreak notification and reporting transparency of states, increasingly scrutinized by the algorithmic gaze of syndromic surveillance.

Keywords: algorithms, global health, pandemic, surveillance

Procedia PDF Downloads 170
11701 Optimization of Friction Stir Welding Parameters for Joining Aluminium Alloys using Response Surface Methodology and Artificial Neural Network

Authors: A. M. Khourshid, A. M. El-Kassas, I. Sabry

Abstract:

The objective of this work was to investigate the mechanical properties in order to demonstrate the feasibility of friction stir welding for joining Al 6061 aluminium alloys. Welding was performed on pipe with different thickness (2, 3 and 4 mm), five rotational speeds (485, 710, 910, 1120 and 1400 rpm) and a traverse speed of 4mm/min. This work focuses on two methods which are artificial neural networks using software and Response Surface Methodology (RSM) to predict the tensile strength, the percentage of elongation and hardness of friction stir welded 6061 aluminium alloy. An Artificial Neural Network (ANN) model was developed for the analysis of the friction stir welding parameters of 6061 pipe. Tensile strength, the percentage of elongation and hardness of weld joints were predicted by taking the parameters tool rotation speed, material thickness and axial force as a function. A comparison was made between measured and predicted data. Response Surface Methodology (RSM) was also developed and the values obtained for the response tensile strength, the percentage of elongation and hardness are compared with measured values. The effect of FSW process parameters on mechanical properties of 6061 aluminium alloy has been analysed in detail.

Keywords: friction stir welding, aluminium alloy, response surface methodology, artificial neural network

Procedia PDF Downloads 279
11700 Safety Management on Construction Sites

Authors: Jonathan Doku

Abstract:

The study's goal was to evaluate construction site safety management in Ghana. The construction sector has long been seen as a high-risk business. It entails a variety of hazardous and challenging labor duties, such as lifting and working at a height, among others. The accident rate is a standard indicator for comparing the safety performance of construction projects. Because of its high-risk and fast-changing work environment, the construction business is regarded as one of the industries with the highest accident rates in the world. Many mishaps and work-related diseases have occurred there, and construction workers are particularly vulnerable to catastrophic calamities such as falls, collapses, and burial. The study's main goals were to discover characteristics that have a substantial impact on construction site safety, to evaluate the safety management methods utilized on construction sites, and to assess the obstacles associated with construction site safety management. The study was conducted using a quantitative research method and a purposive sampling strategy. Google forms were used to distribute self-administered surveys to 85 responders. 72 of the 85 questionnaires were completed and submitted for analysis, accounting for 84.7 percent of the total. The variables were analyzed using descriptive statistics, mean score ranking, and Cronbach's Alpha Coefficient to ensure the scale's reliability. The formal safety organization structure and the Safety checklist were identified as the key practices of safety management on site as part of the study goals. In addition, it was discovered that the most serious problem with safety management is ineffective supervision. To guarantee efficient monitoring and proper implementation of health and safety rules on building sites, management must be on the ball.

Keywords: construction, safety, risk, management

Procedia PDF Downloads 61
11699 Anticancer Effect of Resveratrol-Loaded Gelatin Nanoparticles in NCI-H460 Non-Small Cell Lung Carcinoma Cell Lines

Authors: N. Rajendra Prasad

Abstract:

Resveratrol (RSV), a grape phytochemical, has drawn greater attention because of its beneficial ef-fects against cancer. However, RSV has some draw-backs such as unstabilization, poor water solubility and short biological half time, which limit the utili-zation of RSV in medicine, food and pharmaceutical industries. In this study, we have encapsulated RSV in gelatin nanoparticles (GNPs) and studied its anti-cancer efficacy in NCI-H460 lung cancer cells. SEM and DLS studies have revealed that the prepared RSV-GNPs possess spherical shape with a mean diameter of 294 nm. The successful encapsulation of RSV in GNPs has been achieved by the cross-linker glutaraldehyde probably through Schiff base reaction and hydrogen bond interaction. Spectrophotometric analysis revealed that the max-imum of 93.6% of RSV has been entrapped in GNPs. In vitro drug release kinetics indicated that there was an initial burst release followed by a slow and sustained release of RSV from GNPs. The prepared RSV-GNPs exhibited very rapid and more efficient cellular uptake than free RSV. Further, RSV-GNPs treatment showed greater antiproliferative efficacy than free RSV treatment in NCI-H460 cells. It has been found that greater ROS generation, DNA damage and apoptotic incidence in RSV-GNPs treated cells than free RSV treatment. Erythrocyte aggregation assay showed that the prepared RSV-GNPs formulation elicit no toxic response. HPLC analysis revealed that RSV-GNPs was more bioavailable and had a longer half-life than free RSV. Hence, GNPs carrier system might be a promising mode for controlled delivery and for improved therapeutic index of poorly water soluble RSV.

Keywords: resveratrol, coacervation, anticancer gelatin nanoparticles, lung cancer, controlled release

Procedia PDF Downloads 434
11698 Evaluation of Correct Usage, Comfort and Fit of Personal Protective Equipment in Construction Work

Authors: Anna-Lisa Osvalder, Jonas Borell

Abstract:

There are several reasons behind the use, non-use, or inadequate use of personal protective equipment (PPE) in the construction industry. Comfort and accurate size support proper use, while discomfort, misfit, and difficulties to understand how the PPEs should be handled inhibit correct usage. The need for several protective equipments simultaneously might also create problems. The purpose of this study was to analyse the correct usage, comfort, and fit of different types of PPEs used for construction work. Correct usage was analysed as guessability, i.e., human perceptions of how to don, adjust, use, and doff the equipment, and if used as intended. The PPEs tested individually or in combinations were a helmet, ear protectors, goggles, respiratory masks, gloves, protective cloths, and safety harnesses. First, an analytical evaluation was performed with ECW (enhanced cognitive walkthrough) and PUEA (predictive use error analysis) to search for usability problems and use errors during handling and use. Then usability tests were conducted to evaluate guessability, comfort, and fit with 10 test subjects of different heights and body constitutions. The tests included observations during donning, five different outdoor work tasks, and doffing. The think-aloud method, short interviews, and subjective estimations were performed. The analytical evaluation showed that some usability problems and use errors arise during donning and doffing, but with minor severity, mostly causing discomfort. A few use errors and usability problems arose for the safety harness, especially for novices, where some could lead to a high risk of severe incidents. The usability tests showed that discomfort arose for all test subjects when using a combination of PPEs, increasing over time. For instance, goggles, together with the face mask, caused pressure, chafing at the nose, and heat rash on the face. This combination also limited sight of vision. The helmet, in combination with the goggles and ear protectors, did not fit well and caused uncomfortable pressure at the temples. No major problems were found with the individual fit of the PPEs. The ear protectors, goggles, and face masks could be adjusted for different head sizes. The guessability for how to don and wear the combination of PPE was moderate, but it took some time to adjust them for a good fit. The guessability was poor for the safety harness; few clues in the design showed how it should be donned, adjusted, or worn on the skeletal bones. Discomfort occurred when the straps were tightened too much. All straps could not be adjusted for somebody's constitutions leading to non-optimal safety. To conclude, if several types of PPEs are used together, discomfort leading to pain is likely to occur over time, which can lead to misuse, non-use, or reduced performance. If people who are not regular users should wear a safety harness correctly, the design needs to be improved for easier interpretation, correct position of the straps, and increased possibilities for individual adjustments. The results from this study can be a base for re-design ideas for PPE, especially when they should be used in combinations.

Keywords: construction work, PPE, personal protective equipment, misuse, guessability, usability

Procedia PDF Downloads 74
11697 Gender Inequality in the Workplace: A Literature Review on the Discrimination of Women by Human Resources Instruments

Authors: Katja Wiedemann, Melinda Gainschnigg

Abstract:

This paper deals with gender inequality in companies. In the context of this paper, it is analyzed how women are discriminated by means of Human Resources instruments. The existing gender inequality is made apparent by the ‘Equal Pay Day. Women in Austria work without payment from 20 October onwards, which represents inequality of 21.7 percent points. This gender pay gap is due to the unequal distribution of paid and unpaid work between men and women. Since the majority of activities related to the family and care are carried out by women, there are human capital deficits on women’s side. In addition to the discrimination of women in compensation, there are also discrimination cases caused by other Human Resources instruments. The aim of this paper is to analyze the use of Human Resources instruments with regard to the discrimination of women and to identify measures to counteract this discrimination. Within the scope of this paper, possible instructions for companies on how to design and implement Human Resources instruments will be elaborated. Therefore personnel planning, recruiting, workforce management, compensation, and leadership are used as the basis for that analysis. The data were collected by a literature review and evaluated by means of a summary content analysis. The literature analysis includes papers of scientific journals from various business fields. On the basis of the results of the literature review, it is clear that women are discriminated by all analyzed Human Resources instruments. As a result, existing potentials are not optimally used. In order to limit or even prevent this loss of potential, companies must take specific measures to counteract the discrimination of women.

Keywords: employment issues, gender inequality , women's studies, workplace

Procedia PDF Downloads 230
11696 Senior Leadership Team Coaching in Action: Creating High-Performance Teams

Authors: Siqi Fang, Jingxi Hou

Abstract:

Positive psychology and coaching psychology share a number of fundamental assumptions and common themes. Blending positive psychology, mindfulness, and coaching psychology, our work in team coaching with leaders enhances both leadership and team effectiveness. Although individual coaching has proven to be effective, this article advocates the benefits of leadership coaching in team settings, because durable changes in leadership behaviors are more likely to occur. Does leadership team coaching really work? Does it help improve senior leadership team effectiveness and productivity? This action research study answers these questions by tracking the progress of three typical senior leadership teams consisting of 31 executives participating in a six-month team coaching program. Assessments (pre- and post), workshops, and feedback based on ego development theories and mindfulness were applied to upgrade the senior leadership teams’ transformational stages and reframe their organizational leadership cultures. Results suggest that the team effectiveness of the three leadership teams increased up to 43 percent according to post-survey feedback from superior, direct report, and peers. Discussion is offered to show that senior leadership team coaching help teams to achieve a consensus on common purposes, establish a foundation of trust, improve collective skills, and promote efficient operation. All factors translate into better team performance. Implications of the results for future executive development programs are discussed and specific recommendations are provided.

Keywords: action research, ego development, mindfulness, senior leadership team coaching, team effectiveness, transformational stages

Procedia PDF Downloads 359
11695 Effect of Instructional Materials on Academic Performance in Heat Transfer Concept among Secondary School Physics Students in Fagge Educational Zone, Kano State, Nigeria

Authors: Shehu Aliyu

Abstract:

This study investigated the effects of instructional materials on academic achievement among senior secondary school students on the concept of Heat Transfer in physics in Fagge Educational Zone, Kano State Nigeria. The population consisted of SSII students from 10 public schools. Out of this, 87 students were randomly selected from which 24 males and 22 females formed the experimental group and 41 students as control group. A quasi experiential design with pretest and post-test for both the groups was adopted. Two research questions and null hypotheses guided the conduct of the study. The experimental group was exposed to teaching using instructional materials while the control group was taught using the normal lecture mode. Head Transfer Performance Test (HTPT) was used for data collection. The instrument was validated by experts in the science education field. A Pearson Product Moment Correlation (PPMC) was used to determine the reliability co-efficient and was found to be r=0.83. The research questions were answered using descriptive statistics while the hypotheses were tested at p≤ 0.05 level of significance using t-test. The result obtained from the data analysis showed that students in experimental group performed significantly better than those in the control group and that there was no significant difference in the academic performance between male and female students in the experimental group. Based on the findings of this study, it was recommended among others that the physics teachers should be receiving regular training on the importance of using instructional materials whether ready made or improved in their teaching.

Keywords: heat transfer, physics, instructional materials, academic performance

Procedia PDF Downloads 167