Search results for: special needs education teachers
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9949

Search results for: special needs education teachers

3619 Transforming the Human Resources of the Company in Innovation Factors: Educational Tools

Authors: Ciolomic Ioana Andreea, Farcas Teodora, Tiron-Tudor Adriana

Abstract:

Investments in research and innovation are widely acknowledged as being crucial drivers for economic growth, for job-creation and to secure social and economic welfare. The aim of this article is to disseminate the results of a Leonardo da Vinci Innovation Transfer project, AdapTykes Adaptation of trainings based up on the Finnish Workplace Development Programme. This project aims to analyses the adaptability of the Finnish model to the economic and political environment of the two emergent countries Romania and Hungary, in order to develop workplace innovation. The focus of this paper is to present the adaptability of the Finnish model to the Romanian context.

Keywords: innovation, human resources, education, tools

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3618 Fieldwork on the Way That Greeks View the Migration under the 'Veil of Ignorance'

Authors: Nikoletta G. Karytsioti

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The European Union’s function and effectiveness are still an issue that minds, bringing about division even in the member-states interior. Recently, more serious issues have been added in the Union’s malfunction, which affects not only the Union’s function but also their residents’ safety. One of these issues is the migration crisis, which frustrates the European Union’s balances and the stability. The present paper’s aim to frame and interpret the Greek public opinion in basic migration matters, throughout the political philosophy and specifically via John Rawls ‘Theory of Justice’. The theory is deployed to examine if it may be used in a practical way, on a tangible issue and in a specific area. In order to obtain a real frame of the public opinion about the matter of migration, a questionnaire was addressed to Greek people. The sample was chosen for three main reasons: a) Greeks are experienced in the migration as they had migrated in the past, b) many young people migrated the recent years after the debt crisis, c) Greece is a reception state. Being based in the Theory of Justice and specifically in the ‘veil of ignorance’, is tried to overcome the obstacles of human nature’s subjectivity, while examining the variations in the responses per social group. The questionnaire will have demographic questions and special interest questions, related with the crisis, before and after ‘the veil of ignorance’. The paper’s originality comes from the fact that it is the first time that a philosophical theory is used to examine the migration issue in a practical manner. The main goals of the paper are three: - To examine the differences/similarities in the responses before and after the veil of ignorance, - to reveal opinions on migration crisis from E.U. citizens and - to confirm or not the practical usefulness of the Political Philosophy as a highlighting tool

Keywords: European Union, immigrants, migration crisis, political philosophy, theory of justice, veil of ignorance

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3617 Thematic English Textbook on Tasks Designed for a Public Educational Brazilian Context: Issues and Contributions

Authors: Fernanda Goulart, Rita de Cássia Barbirato

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Task-based language teaching has received attention among researchers as it has been pointed out with the potential to provide more significant opportunities for using the target language and therefore generate successful language acquisition. Nevertheless, in the Brazilian context, few studies have analyzed the potential of tasks in English language acquisition. There is also a need for textbooks to meet the needs of Brazilian students. This work is part of doctoral research in its initial phase. It aims to demonstrate and discuss thematic textbook samples on tasks designed to be applied among high school and undergraduate students in a public technological educational context in São Paulo State, Brazil. It is a qualitative study. The data collection process for course design and textbook development initially included a survey administered to 159 students. Questions related to students’ English background knowledge, main learning interests, and needs. Most students reported difficulties communicating in English and showed a strong interest in a communicative English course. The theme “Cultural diversity” was chosen among other options provided. The textbook was then designed and comprised nine task cycles divided into four sequences. Cycles were composed of pre-tasks, tasks, and post-tasks. The main findings of this first phase of the research revealed that designing a task-based textbook is not easy and requires the necessary steps and lots of effort to meet students’ language needs. Several revisions were needed before the conclusion of the final version of the textbook. The material will be further applied in a three-month English course. In this presentation, we hope to contribute to discussions in research on task-based teaching. Also, we intend to support teachers with their knowledge of tasks and thematic material development in this field.

Keywords: task-based language teaching, language acquisition, English language teaching, task cycles

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3616 An Efficient Approach for Shear Behavior Definition of Plant Stalk

Authors: M. R. Kamandar, J. Massah

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The information of the impact cutting behavior of plants stalk plays an important role in the design and fabrication of plants cutting equipment. It is difficult to investigate a theoretical method for defining cutting properties of plants stalks because the cutting process is complex. Thus, it is necessary to set up an experimental approach to determine cutting parameters for a single stalk. To measure the shear force, shear energy and shear strength of plant stalk, a special impact cutting tester was fabricated. It was similar to an Izod impact cutting tester for metals but a cutting blade and data acquisition system were attached to the end of pendulum's arm. The apparatus was included four strain gages and a digital indicator to show the real-time cutting force of plant stalk. To measure the shear force and also testing the apparatus, two plants’ stalks, like buxus and privet, were selected. The samples (buxus and privet stalks) were cut under impact cutting process at four loading rates 1, 2, 3 and 4 m.s-1 and three internodes fifth, tenth and fifteenth by the apparatus. At buxus cutting analysis: the minimum value of cutting energy was obtained at fifth internode and loading rate 4 m.s-1 and the maximum value of shear energy was obtained at fifteenth internode and loading rate 1 m.s-1. At privet cutting analysis: the minimum value of shear consumption energy was obtained at fifth internode and loading rate: 4 m.s-1 and the maximum value of shear energy was obtained at fifteenth internode and loading rate: 1 m.s-1. The statistical analysis at both plants showed that the increase of impact cutting speed would decrease the shear consumption energy and shear strength. In two scenarios, the results showed that with increase the cutting speed, shear force would decrease.

Keywords: Buxus, Privet, impact cutting, shear energy

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3615 Geoeducation Strategies for Teaching Natural Hazards in Schools

Authors: Carlos Alberto Ríos Reyes, Andrés Felipe Mejía Durán, Oscar Mauricio Castellanos Alarcón

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There is no doubt of great importance to make it known that planet Earth is an entity in constant change and transformation; processes such as construction and destruction are part of the evolution of the territory. Geoeducation workshops represent a significant contribution to the search for educational projects focused on teaching relevant geoscience topics to make natural threats known in schools through recreational and didactic activities. This initiative represents an educational alternative that must be developed with the participation of primary and secondary schools, universities, and local communities. The methodology is based on several phases, which include: diagnosis to know the best teaching method for basic concepts and establish a starting point for the topics to be taught, as well as to identify areas and concepts that need to be reinforced and/or deepened; design of activities that involve all students regardless of their ability or level; use of accessible materials and experimentation to support clear and concise explanations for all students; adaptation of the teaching-learning process to individual needs; sensitization about natural threats; and evaluation and feedback. It is expected to offer a series of activities and materials as a significant contribution to the search for educational projects focused on teaching relevant geoscientific topics such as natural threats associated with earthquakes, volcanic eruptions, floods, landslides, etc. The major findings of this study are the pedagogical strategies that primary and secondary school teachers can appropriate to face the challenge of transferring geological knowledge and to advise decision-makers and citizens on the importance of geosciences for daily life. We conclude that the knowledge of the natural threats to our planet is very important to contribute to mitigating their risk.

Keywords: workshops, geoeducation, curriculum, geosciences, natural threats

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3614 Consumer Preferences towards Sorbets: A Questionnaire Study

Authors: Kinga Topolska, Agnieszka Filipiak-Florkiewicz, Adam Florkiewicz, Daria Chechelska, Iwona Cieślik, Ewa Cieślik

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Food choice is a complex human behaviour, that is influenced by many interrelating factors. It is important to understand what consumers really want to eat. Nowadays, the growing popularity of frozen desserts is observed. Among them, sorbets are of the special interest. They are made primarily of fruit juice or fruit purée, water and sugar. A questionnaire study was done to evaluate the consumer preferences towards sorbets. A hundred respondents were included in the study. The respondents answered the questions concerning, inter alia, on the favourite taste of sorbets, additional ingredients (pieces of fruits, nuts etc.), the reason for choosing the product and also the opinion about potential purchasing or not the new product. Women, more frequently than men, indicated strawberry sorbet or the product on the basis of citrus fruits as a favourite one. In turn, 14% of men chose the apple taste. Pieces of chocolate were chosen by most of respondents. Men, more often than women, regarded raisins, alcohol and nuts as the most desirable additional ingredients of sorbets. The candied fruits and spices were indicated more frequently by women. Most of respondents indicated the taste as the major reason for sorbet buying. In turn, for 20% women the most important determinant was the care for their figure. It was observed that more than a half of women regarded sorbets as healthier than traditional ice creams. Answering the question: 'If you had the opportunity to try a new sorbet, containing the ingredient with proven healthy properties, would you buy it?', significantly more men than women answered 'yes, because I like novelty'. Meanwhile, for 14% respondents (independently of gender) it would be only a publicity stunt. Knowing what the consumers desire in selecting a product, is a very important information to design and offer them a new one. Sorbets could be an interesting alternative to ice creams.

Keywords: consumer, preferences, sorbets, questionnaire study

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3613 Molecular Insights into the Genetic Integrity of Long-Term Micropropagated Clones Using Start Codon Targeted (SCoT) Markers: A Case Study with Ansellia africana, an Endangered, Medicinal Orchid

Authors: Paromik Bhattacharyya, Vijay Kumar, Johannes Van Staden

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Micropropagation is an important tool for the conservation of threatened and commercially important plant species of which orchids deserve special attention. Ansellia africana is one such medicinally important orchid species having much commercial significance. Thus, development of regeneration protocols for producing clonally stable regenerates using axillary buds is of much importance. However, for large-scale micropropagation to become not only successful but also acceptable by end-users, somaclonal variations occurring in the plantlets need to be eliminated. In the light of the various factors (genotype, ploidy level, in vitro culture age, explant and culture type, etc.) that may account for the somaclonal variations of divergent genetic changes at the cellular and molecular levels, genetic analysis of micropropagated plants using a multidisciplinary approach is of utmost importance. In the present study, the clonal integrity of the long term micropropagated A. africana plants were assessed using advanced molecular marker system i.e. Start Codon Targeted Polymorphism (SCoT). Our studies recorded a clonally stable regeneration protocol for A. africana with a very high degree of clonal fidelity amongst the regenerates. The results obtained from these molecular analyses could help in modifying the regeneration protocols for obtaining clonally stable true to type plantlets for sustainable commercial use.

Keywords: medicinal orchid micropropagation, start codon targeted polymorphism (SCoT), RAP), traditional African pharmacopoeia, genetic fidelity

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3612 Moderating Effects of Family Structure on College Achievement

Authors: Jennifer Knudsen

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This study observes the moderating effects of family structure on College Achievement across cohorts. Over the past half-century, social stigmas surrounding non-traditional families have shifted, as they make up an increasing proportion of American families. Using the General Social Survey, this study employs a varying coefficient model to test if family structure moderates the effects of other background variables on respondents’ educational attainment. Initial analysis suggests that living in alternative family arrangements has an increasingly negative effect on college achievement, whereas living in an intact family with a mother and father has a positive effect on college achievement.

Keywords: education, family, college, family structure

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3611 Producing of Amorphous-Nanocrystalline Composite Powders

Authors: K. Tomolya, D. Janovszky, A. Sycheva, M. Sveda, A. Roosz

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CuZrAl amorphous alloys have attracted high interest due to unique physical and mechanical properties, which can be enhanced by adding of Ni and Ti elements. It is known that this properties can be enhanced by crystallization of amorphous alloys creating nanocrystallines in the matrix. The present work intends to produce nanosized crystalline parti-cle reinforced amorphous matrix composite powders by crystallization of amorphous powders. As the first step the amorphous powders were synthe-tized by ball-milling of crystalline powders. (Cu49Zr45Al6) 80Ni10Ti10 and (Cu49Zr44Al7) 80Ni10Ti10 (at%) alloys were ball-milled for 12 hours in order to reach the fully amorphous structure. The impact en-ergy of the balls during milling causes the change of the structure in the powders. Scanning electron microscopical (SEM) images shows that the phases mixed first and then changed into a fully amorphous matrix. Furthermore, nanosized particles in the amorphous matrix were crystallized by heat treatment of the amorphous powders that was confirmed by TEM measurement. It was of importance to define the tem-perature when the amorphous phase starts to crystal-lize. Amorphous alloys have a special heating curve and characteristic temperatures, which can be meas-ured by differential scanning calorimetry (DSC). A typical DSC curve of an amorphous alloy exhibits an endothermic event characteristic of the equilibrium glass transition (Tg) and a distinct undercooled liquid region, followed by one or two exothermic events corresponding to crystallization processes (Tp). After measuring the DSC traces of the amorphous powders, the annealing temperatures should be determined between Tx and Tp. In our experiments several temperatures from the annealing temperature range were selected and de-pendency of crystallized nanoparticles fraction on their hardness was investigated.

Keywords: amorphous structure, composite, mechanical milling, powder, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), transmission electronmocroscopy (TEM)

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3610 A Serious Game to Upgrade the Learning of Organizational Skills in Nursing Schools

Authors: Benoit Landi, Hervé Pingaud, Jean-Benoit Culie, Michel Galaup

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Serious games have been widely disseminated in the field of digital learning. They have proved their utility in improving skills through virtual environments that simulate the field where new competencies have to be improved and assessed. This paper describes how we created CLONE, a serious game whose purpose is to help nurses create an efficient work plan in a hospital care unit. In CLONE, the number of patients to take care of is similar to the reality of their job, going far beyond what is currently practiced in nurse school classrooms. This similarity with the operational field increases proportionally the number of activities to be scheduled. Moreover, very often, the team of nurses is composed of regular nurses and nurse assistants that must share the work with respect to the regulatory obligations. Therefore, on the one hand, building a short-term planning is a complex task with a large amount of data to deal with, and on the other, good clinical practices have to be systematically applied. We present how reference planning has been defined by addressing an optimization problem formulation using the expertise of teachers. This formulation ensures the gameplay feasibility for the scenario that has been produced and enhanced throughout the game design process. It was also crucial to steer a player toward a specific gaming strategy. As one of our most important learning outcomes is a clear understanding of the workload concept, its factual calculation for each caregiver along time and its inclusion in the nurse reasoning during planning elaboration are focal points. We will demonstrate how to modify the game scenario to create a digital environment in which these somewhat abstract principles can be understood and applied. Finally, we give input on an experience we had on a pilot of a thousand undergraduate nursing students.

Keywords: care planning, workload, game design, hospital nurse, organizational skills, digital learning, serious game

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3609 Design of Hybrid Auxetic Metamaterials for Enhanced Energy Absorption under Compression

Authors: Ercan Karadogan, Fatih Usta

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Auxetic materials have a negative Poisson’s ratio (NPR), which is not often found in nature. They are metamaterials that have potential applications in many engineering fields. Mechanical metamaterials are synthetically designed structures with unusual mechanical properties. These mechanical properties are dependent on the properties of the matrix structure. They have the following special characteristics, i.e., improved shear modulus, increased energy absorption, and intensive fracture toughness. Non-auxetic materials compress transversely when they are stretched. The system naturally is inclined to keep its density constant. The transversal compression increases the density to balance the loss in the longitudinal direction. This study proposes to improve the crushing performance of hybrid auxetic materials. The re-entrant honeycomb structure has been combined with a star honeycomb, an S-shaped unit cell, a double arrowhead, and a structurally hexagonal re-entrant honeycomb by 9 X 9 cells, i.e., the number of cells is 9 in the lateral direction and 9 in the vertical direction. The Finite Element (FE) and experimental methods have been used to determine the compression behavior of the developed hybrid auxetic structures. The FE models have been developed by using Abaqus software. The specimens made of polymer plastic materials have been 3D printed and subjected to compression loading. The results are compared in terms of specific energy absorption and strength. This paper describes the quasi-static crushing behavior of two types of hybrid lattice structures (auxetic + auxetic and auxetic + non-auxetic). The results show that the developed hybrid structures can be useful to control collapse mechanisms and present larger energy absorption compared to conventional re-entrant auxetic structures.

Keywords: auxetic materials, compressive behavior, metamaterials, negative Poisson’s ratio

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3608 From Research to Practice: Upcycling Cinema Icons

Authors: Mercedes Rodriguez Sanchez, Laura Luceño Casals

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With the rise of social media, creative people and brands everywhere are constantly generating content. The students with Bachelor's Degrees in Fashion Design use platforms such as Instagram or TikTok to look for inspiration and entertainment, as well as a way to develop their own ideas and share them with a wide audience. Information and Communications Technologies (ICT) have become a central aspect of higher education, virtually affecting every aspect of the student experience. Following the current trend, during the first semester of the second year, a collaborative project across two subjects –Design Management and History of Fashion Design– was implemented. After an introductory class focused on the relationship between fashion and cinema, as well as a brief history of 20th-century fashion, the students freely chose a work team and an iconic look from a movie costume. They researched the selected movie and its sociocultural context, analyzed the costume and the work of the designer, and studied the style, fashion magazines and most popular films of the time. Students then redesigned and recreated the costume, for which they were compelled to recycle the materials they had available at home as an unavoidable requirement of the activity. Once completed the garment, students delivered in-class, team-based presentations supported by the final design, a project summary poster and a making-of video, which served as a documentation tool of the costume design process. The methodologies used include Challenge-Based Learning (CBL), debates, Internet research, application of Information and Communications Technologies, and viewing clips of classic films, among others. After finishing the projects, students were asked to complete two electronic surveys to measure the acquisition of transversal and specific competencies of each subject. Results reveal that this activity helped the students' knowledge acquisition, a deeper understanding of both subjects and their skills development. The classroom dynamic changed. The multidisciplinary approach encouraged students to collaborate with their peers, while educators were better able to keep students' interest and promote an engaging learning process. As a result, the activity discussed in this paper confirmed the research hypothesis: it is positive to propose innovative teaching projects that combine academic research with playful learning environments.

Keywords: cinema, cooperative learning, fashion design, higher education, upcycling

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3607 Parametric Study of 3D Micro-Fin Tubes on Heat Transfer and Friction Factor

Authors: Shima Soleimani, Steven Eckels

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One area of special importance for surface-level study of heat exchangers is tubes with internal micro-fins (< 0.5 mm tall). Micro-finned surfaces are a kind of extended solid surface in which energy is exchanged with water that acts as the source or sink of energy. Significant performance gains are possible for either shell, tube, or double pipe heat exchangers if the best surfaces are identified. The parametric studies of micro-finned tubes that have appeared in the literature left some key parameters unexplored. Specifically, they ignored three-dimensional (3D) micro-fin configurations, conduction heat transfer in the fins, and conduction in the solid surface below the micro-fins. Thus, this study aimed at implementing a parametric study of 3D micro-finned tubes that considered micro-fin height and discontinuity features. A 3D conductive and convective heat-transfer simulation through coupled solid and periodic fluid domains is applied in a commercial package, ANSYS Fluent 19.1. The simulation is steady-state with turbulent water flow cooling inner wall of a tube with micro-fins. The simulation utilizes a constant and uniform temperature on the tube outer wall. Performance is mapped for 18 different simulation cases, including a smooth tube using a realizable k-ε turbulence model at a Reynolds number of 48,928. Results compared the performance of 3D tubes with results for the similar two-dimensional (2D) one. Results showed that the micro-fin height has greater impact on performance factor than discontinuity features in 3D micro-fin tubes. A transformed 3D micro-fin tube can enhance heat transfer and pressure drop up to 21% and 56% compared to a 2D one, respectfully.

Keywords: three-dimensional micro-finned tube, heat transfer, friction factor, heat exchanger

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3606 Nurturing of Children with Results from Their Nature (DNA) Using DNA-MILE

Authors: Tan Lay Cheng (Cheryl), Low Huiqi

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Background: All children learn at different pace. Individualized learning is an approach that tailors to the individual learning needs of each child. When implementing this approach, educators have to base their lessons on the understanding that all students learn differently and that what works for one student may not work for another. In the current early childhood environment, individualized learning is for children with diverse needs. However, a typical developing child is also able to benefit from individualized learning. This research abstract explores the concept of utilizing DNA-MILE, a patented (in Singapore) DNA-based assessment tool that can be used to measure a variety of factors that can impact learning. The assessment report includes the dominant intelligence of the user or, in this case, the child. From the result, a personalized learning plan that is tailored to each individual student's needs. Methods: A study will be conducted to investigate the effectiveness of DNA-MILE in supporting individualized learning. The study will involve a group of 20 preschoolers who were randomly assigned to either a DNA-MILE-assessed group (experimental group) or a control group. 10 children in each group. The experimental group will receive DNA Mile assessments and personalized learning plans, while the control group will not. The children in the experimental group will be taught using the dominant intelligence (as shown in the DNA-MILE report) to enhance their learning in other domains. The children in the control group will be taught using the curriculum and lesson plan set by their teacher for the whole class. Parents’ and teachers’ interviews will be conducted to provide information about the children before the study and after the study. Results: The results of the study will show the difference in the outcome of the learning, which received DNA Mile assessments and personalized learning plans, significantly outperformed the control group on a variety of measures, including standardized tests, grades, and motivation. Conclusion: The results of this study suggest that DNA Mile can be an effective tool for supporting individualized learning. By providing personalized learning plans, DNA Mile can help to improve learning outcomes for all students.

Keywords: individualized, DNA-MILE, learning, preschool, DNA, multiple intelligence

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3605 Dietetics Practice in the Scope of Disease Prevention in Community Settings: A School-Based Obesity Prevention Program

Authors: Elham Abbas Aljaaly, Nahlaa Abdulwahab Khalifa

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The active method of disease prevention is seen as the most affordable and sustainable action to deal with risks of non-communicable diseases such as obesity. This eight-week project aimed to pilot the feasibility and acceptability of a school-based programme, which is proposed to prevent and modify overweight status and possible related risk factors among student girls 'at the intermediate level' in Jeddah city. The programme was conducted through comprehensible approach targeting physical environment and school policies (nutritional/exercise/behavioural approach). The programme was designed to cultivate the personal and environmental awareness in schools for girls. This was applied by promoting healthy eating and physical activity through policies, physical education, healthier options for school canteens, and the creation of school health teams. The prevention programme was applied on 68 students (who agreed to participate) from grades 7th, 8th and 9th. A pre and post assessment questionnaire was employed on 66 students. The questionnaires were designed to obtain information on students' knowledge about health, nutrition and physical activity. Survey questions included information about nutrients, food consumption patterns, food intake and lifestyle. Physical education included training sessions for new opportunities for physical activities to be performed during school or after school hours. A running competition 'to enhance students’ performance for physical activities' was also conducted during the school visit. A visit to the school canteen was conducted to check, observe, record and assess all available food/beverage items and meals. The assessment method was a subjective method for the type of food/beverages if high in saturated fat, salt and sugar (HFSS) or non-HFSS. The school canteen administrators were encouraged to provide healthy food/beverage items and a sample healthy canteen was provided for implementation. Two healthy options were introduced to the school canteen. A follow up for students’ preferences for the introduced options and the purchasing power were assessed. Thirty-eight percent of young girls (n=26) were not participating in any form of physical activities inside or outside school. Skipping breakfast was stated by 42% (n=28) of students with no daily consumption (19%, n=13) for fruit/vegetables. Significant changes were noticed in students’ (n=66) overall responses to the pre and post questions (P value=.001). All students had participated in the conducted running competition sessions and reported satisfaction and enjoyment about the sessions. No absence was reported by the research team for attending physical education and activity sessions throughout the delivered programme. The purchasing power of the introduced healthy options of 'Salad and oatmeal' was increased to 18% in 8 weeks at the school canteen, and slightly affected the purchase for other less healthy options. The piloted programme indorsed better health and nutrition knowledge, healthy eating and lifestyle attitude, which could help young girls to obtain sustainable changes. It is expected that the outcomes of the programme will be a cornerstone for the futuristic national study that will assist policy makers and participants to build a knowledgeable health promotion scenario and make sure that school students have access to healthy foods, physical exercise and healthy lifestyle.

Keywords: adolescents, diet, exercise, behaviours, overweight/obesity, prevention-intervention programme, Saudi Arabia, schoolgirls

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3604 Finite Deformation of a Dielectric Elastomeric Spherical Shell Based on a New Nonlinear Electroelastic Constitutive Theory

Authors: Odunayo Olawuyi Fadodun

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Dielectric elastomers (DEs) are a type of intelligent materials with salient features like electromechanical coupling, lightweight, fast actuation speed, low cost and high energy density that make them good candidates for numerous engineering applications. This paper adopts a new nonlinear electroelastic constitutive theory to examine radial deformation of a pressurized thick-walled spherical shell of soft dielectric material with compliant electrodes on its inner and outer surfaces. A general formular for the internal pressure, which depends on the deformation and a potential difference between boundary electrodes or uniform surface charge distributions, is obtained in terms of special function. To illustrate the effects of an applied electric field on the mechanical behaviour of the shell, three different energy functions with distinct mechanical properties are employed for numerical purposes. The observed behaviour of the shells is preserved in the presence of an applied electric field, and the influence of the field due to a potential difference declines more slowly with the increasing deformation to that produced by a surface charge. Counterpart results are then presented for the thin-walled shell approximation as a limiting case of a thick-walled shell without restriction on the energy density. In the absence of internal pressure, it is obtained that inflation is caused by the application of an electric field. The resulting numerical solutions of the theory presented in this work are in agreement with those predicted by the generally adopted Dorfmann and Ogden model.

Keywords: constitutive theory, elastic dielectric, electroelasticity, finite deformation, nonlinear response, spherical shell

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3603 Knowledge, Attitude and Practices of Contraception among the Married Women of Reproductive Age Group in Selected Wards of Dharan Sub-Metropolitan City

Authors: Pratima Thapa

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Background: It is very critical to understand that awareness of family planning and proper utilization of contraceptives is an important indicator for reducing maternal and neonatal mortality and morbidity. It also plays an important role in promoting reproductive health of the women in an underdeveloped country like ours. Objective: To assess knowledge, attitude and practices of contraception among married women of reproductive age group in selected wards of Dharan Sub-Metropolitan City. Materials and methods: A cross-sectional descriptive study was conducted among 209 married women of reproductive age. Simple random sampling was used to select the wards, population proportionate sampling for selecting the sample numbers from each wards and purposive sampling for selecting each sample. Semi-structured questionnaire was used to collect data. Descriptive and inferential statistics were used to interpret the data considering p-value 0.05. Results: The mean ± SD age of the respondents was 30.01 ± 8.12 years. Majority 92.3% had ever heard of contraception. Popular known method was Inj. Depo (92.7%). Mass media (85.8%) was the major source of information. Mean percentage score of knowledge was 45.23%.less than half (45%) had adequate knowledge. Majority 90.4% had positive attitude. Only 64.6% were using contraceptives currently. Misbeliefs and fear of side effects were the main reason for not using contraceptives. Education, occupation, and total income of the family was associated with knowledge regarding contraceptives. Results for Binary Logistic Regression showed significant correlates of attitude with distance to the nearest health facility (OR=7.97, p<0.01), education (OR=0.24, p<0.05) and age group (0.03, p<0.01). Regarding practice, likelihood of being current user of contraceptives increased significantly by being literate (OR=5.97, p<0.01), having nuclear family (OR=4.96, p<0.01), living in less than 30 minute walk distance from nearest health facility (OR=3.34, p<0.05), women’s participation in decision making regarding household and fertility choices (OR=5.23, p<0.01) and husband’s support on using contraceptives (OR=9.05, p<0.01). Significant and positive correlation between knowledge-attitude, knowledge-practice and attitude-practice were observed. Conclusion: Results of the study indicates that there is need to increase awareness programs in order to intensify the knowledge and practices of contraception. The positive correlation indorses that better knowledge can lead to positive attitude and hence good practice. Further, projects aiming to increase better counselling about contraceptives, its side effects and the positive effects that outweighs the negative aspects should be enrolled appropriately.

Keywords: attitude, contraceptives, knowledge, practice

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3602 National Branding through Education: South Korean Image in Romania through the Language Textbooks for Foreigners

Authors: Raluca-Ioana Antonescu

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The paper treats about the Korean public diplomacy and national branding strategies, and how the Korean language textbooks were used in order to construct the Korean national image. The field research of the paper stands at the intersection between Linguistics and Political Science, while the problem of the research is the role of language and culture in national branding process. The research goal is to contribute to the literature situated at the intersection between International Relations and Applied Linguistics, while the objective is to conceptualize the idea of national branding by emphasizing a dimension which is not much discussed, and that would be the education as an instrument of the national branding and public diplomacy strategies. In order to examine the importance of language upon the national branding strategies, the paper will answer one main question, How is the Korean language used in the construction of national branding?, and two secondary questions, How are explored in literature the relations between language and national branding construction? and What kind of image of South Korea the language textbooks for foreigners transmit? In order to answer the research questions, the paper starts from one main hypothesis, that the language is an essential component of the culture, which is used in the construction of the national branding influenced by traditional elements (like Confucianism) but also by modern elements (like Western influence), and from two secondary hypothesis, the first one is that in the International Relations literature there are little explored the connections between language and national branding, while the second hypothesis is that the South Korean image is constructed through the promotion of a traditional society, but also a modern one. In terms of methodology, the paper will analyze the textbooks used in Romania at the universities which provide Korean Language classes during the three years program B.A., following the dialogs, the descriptive texts and the additional text about the Korean culture. The analysis will focus on the rank status difference, the individual in relation to the collectivity, the respect for the harmony, and the image of the foreigner. The results of the research show that the South Korean image projected in the textbooks convey the Confucian values and it does not emphasize the changes suffered by the society due to the modernity and globalization. The Westernized aspect of the Korean society is conveyed more in an informative way about the Korean international companies, Korean internal development (like the transport or other services), but it does not show the cultural changed the society underwent. Even if the paper is using the textbooks which are used in Romania as a teaching material, it could be used and applied at least to other European countries, since the textbooks are the ones issued by the South Korean language schools, which other European countries are using also.

Keywords: confucianism, modernism, national branding, public diplomacy, traditionalism

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3601 A Predictive Model of Supply and Demand in the State of Jalisco, Mexico

Authors: M. Gil, R. Montalvo

Abstract:

Business Intelligence (BI) has become a major source of competitive advantages for firms around the world. BI has been defined as the process of data visualization and reporting for understanding what happened and what is happening. Moreover, BI has been studied for its predictive capabilities in the context of trade and financial transactions. The current literature has identified that BI permits managers to identify market trends, understand customer relations, and predict demand for their products and services. This last capability of BI has been of special concern to academics. Specifically, due to its power to build predictive models adaptable to specific time horizons and geographical regions. However, the current literature of BI focuses on predicting specific markets and industries because the impact of such predictive models was relevant to specific industries or organizations. Currently, the existing literature has not developed a predictive model of BI that takes into consideration the whole economy of a geographical area. This paper seeks to create a predictive model of BI that would show the bigger picture of a geographical area. This paper uses a data set from the Secretary of Economic Development of the state of Jalisco, Mexico. Such data set includes data from all the commercial transactions that occurred in the state in the last years. By analyzing such data set, it will be possible to generate a BI model that predicts supply and demand from specific industries around the state of Jalisco. This research has at least three contributions. Firstly, a methodological contribution to the BI literature by generating the predictive supply and demand model. Secondly, a theoretical contribution to BI current understanding. The model presented in this paper incorporates the whole picture of the economic field instead of focusing on a specific industry. Lastly, a practical contribution might be relevant to local governments that seek to improve their economic performance by implementing BI in their policy planning.

Keywords: business intelligence, predictive model, supply and demand, Mexico

Procedia PDF Downloads 120
3600 Instructional Design Strategy Based on Stories with Interactive Resources for Learning English in Preschool

Authors: Vicario Marina, Ruiz Elena, Peredo Ruben, Bustos Eduardo

Abstract:

the development group of Educational Computing of the National Polytechnic (IPN) in Mexico has been developing interactive resources at preschool level in an effort to improve learning in the Child Development Centers (CENDI). This work describes both a didactic architecture and a strategy for teaching English with digital stories using interactive resources available through a Web repository designed to be used in mobile platforms. It will be accessible initially to 500 children and worldwide by the end of 2015.

Keywords: instructional design, interactive resources, digital educational resources, story based English teaching, preschool education

Procedia PDF Downloads 468
3599 Whole School Environmental Mapping Framework in Preventing Childhood Obesity in Selangor

Authors: M. A. M. Hayati Adilin, D. Ajau, A. S. Siti Khuzaimah, K. Mastura, R. Nik Muhammad Syafiq, M. N. Noor Fatin Nadiah

Abstract:

The school environment is one of many factors related to the increment of overweight and obesity among children. There is an evidence to suggest that the school environmental factor has an independent effect towards health-related behaviour of children and school culture. It may have a significant impact towards the emergence of childhood obesity through their influence on eating pattern and physical activity level. The objective of this study is to identify the school environmental factors (i.e. physical, economic, political and socio-cultural) towards healthy eating and physical activity of urban and rural primary school children in preventing childhood obesity. This can be identified by examining the compliance of rural and urban school environment with whole-school environmental mapping framework. The study design was a cross-sectional study. A total of 60 schools were randomly selected (30 urban and 30 rural) in Selangor, Western Peninsular Malaysia in 2013 and 60 teachers (responsible for student affairs and the school curriculum) have been interviewed face to face by using a whole school mapping questionnaire followed by observation of the school environment . This study has demonstrated that schools in both areas (rural and urban) comply mostly with the physical environmental mapping (83.3%), followed by socio-cultural environmental mapping, 65%. Meanwhile, the political environmental mappings in both urban and rural schools show a low compliance percentage, which is 56.7%. For economic environmental mapping, only 10% of both schools are complied. As a conclusion, this study has demonstrated that schools in both areas do not fully comply with the whole school environmental mapping framework, especially economic and political. However, holistic approach is needed and many improvements can be proposed to promote healthy eating and physical activities among school children. Government, families and schools as well as communities and the media should be included together with any strategies for preventing childhood obesity.

Keywords: childhood obesity, healthy eating, physical activity, school environment

Procedia PDF Downloads 507
3598 Tardiness and Self-Regulation: Degree and Reason for Tardiness in Undergraduate Students in Japan

Authors: Keiko Sakai

Abstract:

In Japan, all stages of public education aim to foster a zest for life. ‘Zest’ implies solving problems by oneself, using acquired knowledge and skills. It is related to the self-regulation of metacognition. To enhance this, establishing good learning habits is important. Tardiness in undergraduate students should be examined based on self-regulation. Accordingly, we focussed on self-monitoring and self-planning strategies among self-regulated learning factors to examine the causes of tardiness. This study examines the impact of self-monitoring and self-planning learning skills on the degree and reason for tardiness in undergraduate students. A questionnaire survey was conducted, targeted to undergraduate students in University X in the autumn semester of 2018. Participants were 247 (average age 19.7, SD 1.9; 144 males, 101 females, 2 no answers). The survey contained the following items and measures: school year, the number of classes in the semester, degree of tardiness in the semester (subjective degree and objective times), active participation in and action toward schoolwork, self-planning and self-monitoring learning skills, and reason for tardiness (open-ended question). First, the relation between strategies and tardiness was examined by multiple regressions. A statistically significant relationship between a self-monitoring learning strategy and the degree of subjective and objective tardiness was revealed, after statistically controlling the school year and the number of classes. There was no significant relationship between a self-planning learning strategy and the degree of tardiness. These results suggest that self-monitoring skills reduce tardiness. Secondly, the relation between a self-monitoring learning strategy and the reason of tardiness was analysed, after classifying the reason for tardiness into one of seven categories: ‘overslept’, ‘illness’, ‘poor time management’, ‘traffic delays’, ‘carelessness’, ‘low motivation’, and ‘stuff to do’. Chi-square tests and Fisher’s exact tests showed a statistically significant relationship between a self-monitoring learning strategy and the frequency of ‘traffic delays’. This result implies that self-monitoring skills prevent tardiness because of traffic delays. Furthermore, there was a weak relationship between a self-monitoring learning strategy score and the reason-for-tardiness categories. When self-monitoring skill is higher, a decrease in ‘overslept’ and ‘illness’, and an increase in ‘poor time management’, ‘carelessness’, and ‘low motivation’ are indicated. It is suggested that a self-monitoring learning strategy is related to an internal causal attribution of failure and self-management for how to prevent tardiness. From these findings, the effectiveness of a self-monitoring learning skill strategy for reducing tardiness in undergraduate students is indicated.

Keywords: higher-education, self-monitoring, self-regulation, tardiness

Procedia PDF Downloads 131
3597 Role of Family for Grooming a Child: A Protective Step for Vulnerable Child

Authors: Arpita Sabat, Kanaklata Samal

Abstract:

A child is the most innocent being on the earth. It is born innocent but the family, the community, the institution and the world at large always butcher its innocence. This paper aims at the role of family for the development of a child in different ethnic or social groups. Family, in fact, is the nucleus in the growth and development of the child. A child grows up with the idea that a family is the world around him. The child tries to emulate consciously or unconsciously from the surrounding. This imitation has serious impact on the development of the child. It even sometimes cripples or stunts the growth of a mind. It results in the disability of the child. All policies about education or changing of curriculum can not bring about a change in the plight of a child’s life unless there is a serious thinking about the role of a family and the contribution of a family to the development of a child.

Keywords: vulnerable child, grooming, surrounding, role of family

Procedia PDF Downloads 319
3596 Classification on Statistical Distributions of a Complex N-Body System

Authors: David C. Ni

Abstract:

Contemporary models for N-body systems are based on temporal, two-body, and mass point representation of Newtonian mechanics. Other mainstream models include 2D and 3D Ising models based on local neighborhood the lattice structures. In Quantum mechanics, the theories of collective modes are for superconductivity and for the long-range quantum entanglement. However, these models are still mainly for the specific phenomena with a set of designated parameters. We are therefore motivated to develop a new construction directly from the complex-variable N-body systems based on the extended Blaschke functions (EBF), which represent a non-temporal and nonlinear extension of Lorentz transformation on the complex plane – the normalized momentum spaces. A point on the complex plane represents a normalized state of particle momentums observed from a reference frame in the theory of special relativity. There are only two key parameters, normalized momentum and nonlinearity for modelling. An algorithm similar to Jenkins-Traub method is adopted for solving EBF iteratively. Through iteration, the solution sets show a form of σ + i [-t, t], where σ and t are the real numbers, and the [-t, t] shows various distributions, such as 1-peak, 2-peak, and 3-peak etc. distributions and some of them are analog to the canonical distributions. The results of the numerical analysis demonstrate continuum-to-discreteness transitions, evolutional invariance of distributions, phase transitions with conjugate symmetry, etc., which manifest the construction as a potential candidate for the unification of statistics. We hereby classify the observed distributions on the finite convergent domains. Continuous and discrete distributions both exist and are predictable for given partitions in different regions of parameter-pair. We further compare these distributions with canonical distributions and address the impacts on the existing applications.

Keywords: blaschke, lorentz transformation, complex variables, continuous, discrete, canonical, classification

Procedia PDF Downloads 305
3595 A Targeted Maximum Likelihood Estimation for a Non-Binary Causal Variable: An Application

Authors: Mohamed Raouf Benmakrelouf, Joseph Rynkiewicz

Abstract:

Targeted maximum likelihood estimation (TMLE) is well-established method for causal effect estimation with desirable statistical properties. TMLE is a doubly robust maximum likelihood based approach that includes a secondary targeting step that optimizes the target statistical parameter. A causal interpretation of the statistical parameter requires assumptions of the Rubin causal framework. The causal effect of binary variable, E, on outcomes, Y, is defined in terms of comparisons between two potential outcomes as E[YE=1 − YE=0]. Our aim in this paper is to present an adaptation of TMLE methodology to estimate the causal effect of a non-binary categorical variable, providing a large application. We propose coding on the initial data in order to operate a binarization of the interest variable. For each category, we get a transformation of the non-binary interest variable into a binary variable, taking value 1 to indicate the presence of category (or group of categories) for an individual, 0 otherwise. Such a dummy variable makes it possible to have a pair of potential outcomes and oppose a category (or a group of categories) to another category (or a group of categories). Let E be a non-binary interest variable. We propose a complete disjunctive coding of our variable E. We transform the initial variable to obtain a set of binary vectors (dummy variables), E = (Ee : e ∈ {1, ..., |E|}), where each vector (variable), Ee, takes the value of 0 when its category is not present, and the value of 1 when its category is present, which allows to compute a pairwise-TMLE comparing difference in the outcome between one category and all remaining categories. In order to illustrate the application of our strategy, first, we present the implementation of TMLE to estimate the causal effect of non-binary variable on outcome using simulated data. Secondly, we apply our TMLE adaptation to survey data from the French Political Barometer (CEVIPOF), to estimate the causal effect of education level (A five-level variable) on a potential vote in favor of the French extreme right candidate Jean-Marie Le Pen. Counterfactual reasoning requires us to consider some causal questions (additional causal assumptions). Leading to different coding of E, as a set of binary vectors, E = (Ee : e ∈ {2, ..., |E|}), where each vector (variable), Ee, takes the value of 0 when the first category (reference category) is present, and the value of 1 when its category is present, which allows to apply a pairwise-TMLE comparing difference in the outcome between the first level (fixed) and each remaining level. We confirmed that the increase in the level of education decreases the voting rate for the extreme right party.

Keywords: statistical inference, causal inference, super learning, targeted maximum likelihood estimation

Procedia PDF Downloads 91
3594 Building Academic Success and Resilience in Social Work Students: An Application of Self-Determination Theory

Authors: Louise Bunce, Jill Childs, Adam J. Lonsdale, Naomi King

Abstract:

A major concern for the Social Work profession concerns the frequency of burn-out and high turnover of staff. The characteristic of resilience has been identified as playing a crucial role in social workers’ ability to have a satisfying and successful career. Thus a critical role for social work education is to develop resilience in social work students. We currently need to know more about how to train resilient social workers who will also increase the academic standing of the profession. The specific aim of this research was to quantify characteristics that may contribute towards resilience and academic success among student social workers in order to mitigate against the problems of burn-out and low academic standing. These three characteristics were competence (effectiveness at mastering the environment), autonomy (sense of control and free will), and relatedness (interacting and connecting with others), as specified in Self-Determination Theory (SDT). When these three needs are satisfied, we experience higher degrees of motivation to succeed and wellbeing. Thus when these three needs are met in social work students, they have the potential to raise academic standards and promote wellbeing characteristics that contribute to the development of resilience. The current study tested the hypothesis that higher levels of autonomy, competence, and relatedness, as defined by SDT, will predict levels of academic success and resilience in social work students. Two hundred and ten social work students studying at a number of universities completed well-established questionnaires to assess autonomy, competence, and relatedness, level of academic performance and resilience (The Brief Resilience Scale). In this scale, students rated their agreement with items e.g., ‘I bounce back quickly after hard times’ and ‘I usually come through difficult times with little struggle’. After controlling for various factors, including age, gender, ethnicity, and course (undergraduate or postgraduate) preliminary analysis revealed that the components of SDT provided useful predictive value for academic success and resilience. In particular, autonomy and competence provided a useful predictor of academic success while relatedness was a particularly useful predictor of resilience. This study demonstrated that SDT provides a valuable framework for helping to understand what predicts academic success and resilience among social work students. This is relevant because the psychological needs for autonomy, competence and relatedness can be affected by external social and cultural pressures, thus they can be improved by the right type of supportive teaching practices and educational environments. These findings contribute to the growing evidence-base to help build an academic and resilient social worker student body and workforce.

Keywords: education, resilience, self-determination theory, student social workers

Procedia PDF Downloads 325
3593 Characteristics and Prevalence of Anaemia among Mothers and Young Children in Rural Uganda

Authors: Pamela E. Mukaire

Abstract:

Anemia and chronic energy deficiency are significant manifestations of poor nutritional health. Anaemia and nutritional status screening are practical ways for assessing the prevalence of iron deficiency anemia in the food insecure populations with large groups of childbearing women and children. The objective of the study was to assess anemia prevalence and other clinical manifestations of malnutrition among pairs of mothers and young children in rural Uganda. This community cross-sectional study used consecutive sampling to select 214 mothers and 214 children for the study. Data was generated using structured questionnaire, anthropometric measurements and on site analysis for anemia. Bivariable and multivariable analyses were used to assess the effect of different factors on anaemia. Of the 214 mothers, 54.2% were 25-34 years of age, 76.7% unmarried, 63% low income, and 55% had more than four children. Of the 214 children, 57% were female, 50% between 1 to 3 years of age and 35% under one year, and. Overall, 38% of the households had more 4 children under the age of 12. The prevalence of anemia was 48% for mothers and 72% for children; 20.6% of mothers had moderate to severe chronic energy deficiency, 39% had moderately-severe anaemia (10 to 7.1 g/dL). Among children, 53% had moderately-severe anaemia, and 18.2% had severe anaemia. Parity X2 =20, p < .037, number of children under 12 years living in a household X2 =10, p < .015, and child’s gender X2 =6.5, p < .038, had a significant relationship with maternal anaemia. There was a significant relationship between household income X2 =10, p < .005, marital status X2 =9, p < .011, owing a piece of land X2 =18, p < .000, owing home X2 =7, p < .036, and anaemia in children. The prevalence of anemia was high in both mothers and children. Income, marital status, owing a piece of land, owing home, number of children under age 12 in a household were associated with anaemia. Hence, efforts should be made for early diagnosis and management of anaemia deficiencies with special emphasis on those households with large number of children under age 12.

Keywords: anemia, maternal-child, nutrition, rural population

Procedia PDF Downloads 278
3592 WhatsApp Application and Challenges of Radio Broadcasting in Northern Nigeria: Special Interest on FRCN Kaduna

Authors: Aliyu Damri

Abstract:

This study analyzed the emergence of WhatsApp and how employees at the Federal Radio Corporation of Nigeria, Kaduna defined the concept base on their vast broadcasting experiences for over five decades and application of the phenomenon to the radio station. It also analyzed the nature, patterns, dimensions, features, challenges as well as the effects of WhatsApp as a social networking site with specific interest on the radio outlet. Also, the study identified how the radio organization responded to the challenges in an attempt to adapt to the new pattern of broadcasting characterized by many technological transformations. The study further explained in details such skills journalists need to function optimally using WhatsApp as well as the impacts of the WhatsApp on radio broadcasting. It used a combination of published materials, focus group discussion, in depth interviews and participant observation on the activities of the radio stations to address the research questions. The data generated provided insight to better understand the challenges posed to FRCN Kaduna as a result of WhatsApp application and how FRCN Kaduna responded to the challenges. It also provided information on the skills journalists need to function optimally in using WhatsApp application in the radio station. The interview and focus group discussion’s transcripts and the published materials were analyzed along thematic pattern related to the research questions in the study. The dominant response relied heavily on change in the radio station’s organizational and technical integration of newsrooms, the use of a multiskilled workforce, application of a flexible and user-friendly technology in all aspects of production, expansion of the station’s services in to new media such as internet and mobile phones as well as sharing of ideas across different units in the radio outfit.

Keywords: broadcasting, challenge, northern Nigeria, radio, WhatsApp application

Procedia PDF Downloads 122
3591 Islamic Banking Recovery Process and Its Parameters: A Practitioner’s Viewpoints in the Light of Humanising Financial Services

Authors: Muhammad Izzam Bin Mohd Khazar, Nur Adibah Binti Zainudin

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Islamic banking as one of the financial institutions is highly required to maintain a prudent approach to ensure that any financing given is able to generate income to their respective shareholders. As the default payment of customers is probably occurred in the financing, having a prudent approach in the recovery process is a must to ensure that financing losses are within acceptable limits. The objective of this research is to provide the best practice of recovery which is anticipated to benefit both bank and customers. This study will address arising issue on the current practice of recovery process and followed by providing humanising recovery solutions in the light of the Maqasid Shariah. The study identified main issues pertaining to Islamic recovery process which can be categorized into knowledge crisis, process issues, specific treatment cases and system issues. Knowledge crisis is related to direct parties including judges, solicitors and salesperson, while the recovery process issues include the process of issuance of reminder, foreclosure and repossession of asset. Furthermore, special treatment for particular cases also should be observed since different contracts in Islamic banking products will need different treatment. Finally, issues in the system used in the recovery process are still unresolved since the existing technology is still young in this area to embraced Islamic finance requirements and nature of calculation. In order to humanize the financial services in Islamic banking recovery process, we have highlighted four main recommendation to be implemented by Islamic Financial Institutions namely; 1) early deterrent by improving the awareness, 2) improvement of the internal process, 3) reward mechanism, and 4) creative penalty to provide awareness to all stakeholders.

Keywords: humanizing financial services, Islamic Finance, Maqasid Syariah, recovery process

Procedia PDF Downloads 190
3590 Search for APN Permutations in Rings ℤ_2×ℤ_2^k

Authors: Daniel Panario, Daniel Santana de Freitas, Brett Stevens

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Almost Perfect Nonlinear (APN) permutations with optimal resistance against differential cryptanalysis can be found in several domains. The permutation used in the standard for symmetric cryptography (the AES), for example, is based on a special kind of inversion in GF(28). Although very close to APN (2-uniform), this permutation still contains one number 4 in its differential spectrum, which means that, rigorously, it must be classified as 4-uniform. This fact motivates the search for fully APN permutations in other domains of definition. The extremely high complexity associated to this kind of problem precludes an exhaustive search for an APN permutation with 256 elements to be performed without the support of a suitable mathematical structure. On the other hand, in principle, there is nothing to indicate which mathematically structured domains can effectively help the search, and it is necessary to test several domains. In this work, the search for APN permutations in rings ℤ2×ℤ2k is investigated. After a full, exhaustive search with k=2 and k=3, all possible APN permutations in those rings were recorded, together with their differential profiles. Some very promising heuristics in these cases were collected so that, when used as a basis to prune backtracking for the same search in ℤ2×ℤ8 (search space with size 16! ≅244), just a few tenths of a second were enough to produce an APN permutation in a single CPU. Those heuristics were empirically extrapolated so that they could be applied to a backtracking search for APNs over ℤ2×ℤ16 (search space with size 32! ≅2117). The best permutations found in this search were further refined through Simulated Annealing, with a definition of neighbors suitable to this domain. The best result produced with this scheme was a 3-uniform permutation over ℤ2×ℤ16 with only 24 values equal to 3 in the differential spectrum (all the other 968 values were less than or equal 2, as it should be the case for an APN permutation). Although far from being fully APN, this result is technically better than a 4-uniform permutation and demanded only a few seconds in a single CPU. This is a strong indication that the use of mathematically structured domains, like the rings described in this work, together with heuristics based on smaller cases, can lead to dramatic cuts in the computational resources involved in the complexity of the search for APN permutations in extremely large domains.

Keywords: APN permutations, heuristic searches, symmetric cryptography, S-box design

Procedia PDF Downloads 152