351 research outputs found
Investigating the impact of digital technologies on the performance of learning in higher education
The central theme of blended learning is to draw from the best practices of digital learning and face-to-face (F2F) learning to create a cohesive learning experience for improving the performance of learning. Blended learning is becoming increasingly popular across the world because of the benefits it can bring including easy and quick access to learning resources, timely feedback to students, better collaboration, and improved flexible and personalised learning. As a result, many higher education institutions across the world have introduced blended learning. Following the global trend, South Africa has been actively pursuing the development of blended learning in higher education. This leads to the passing of the e-Education policy with specific objectives for improving the development of digital learning in higher education. Despite these efforts, the adoption of digital technologies in higher education in South Africa is unsatisfactory. The performance of individual students in teaching and learning in higher education is deteriorating. This shows the need for better understanding the impact of specific digital technologies in blended learning on the performance of learning in South African higher education. The objective of this research is to investigate the adoption of specific digital technologies in South African higher education for better understanding the effectiveness of these technologies on the performance of learning. Specifically, this research aims to (a) investigate the impact of learning management system (LMS) on the performance of learning, (b) explore the impact of using instant messaging (IM) on the performance of learning, and (c) examine the relative effectiveness of LMS and IM on the performance of learning in higher education in South Africa. A quantitative research methodology is adopted in this study. It employs a pre-test and post-test method for assessing the performance of learning. The study uses a 'treatment' group of LMS + F2F and IM + F2F and a comparison group of F2F design for investigating the relationship between the use of specific digital technologies and the performance of learning in higher education. The data is collected in higher education in South Africa using paper-based surveys. Various statistical analysis techniques including descriptive statistics, t-test, and regression analysis have been used for analysing the data in the study. The study shows that the adoption of LMS and IM has a positive impact on the performance of learning in higher education. The comparative analysis study shows that (a) digital learning using LMS and F2F teaching is more effective than traditional F2F teaching, (b) digital learning using IM and F2F is more effective than traditional F2F teaching, and (c) digital learning using LMS is slightly more effective than blended digital learning using IM on the performance of learning in higher education. Such findings can help to better understand the adoption of specific digital technologies in higher education in South Africa. This study contributes to the digital learning research from both theoretical and practical perspectives. Theoretically, this study (a) explores the impact of specific digital technologies including LMS and IM on the performance of learning, (b) investigates the effect of student characteristics on the performance of learning using specific digital technologies, and (c) conducts a comparative analysis of specific digital technologies in blended learning on the performance of learning in higher education. This study is the first of its kind that conducts a comparative analysis of specific digital technologies on the performance of learning in higher education. Practically, this study provides empirical evidence on the effectiveness of LMS and IM for improving learning. Based on the results of this study, existing policies to encourage the adoption of digital technologies should be supported and strengthened. This study can thus (a) help government departments develop specific policies and strategies for adopting specific digital technologies in order to improve the performance of learning, (b) provide South African higher education institutions with guidelines for facilitating the adoption of digital technologies, and (c) challenges LMS and IM instructional developers and software developers for the continuous development of effective digital technologies for teaching and learning
On multiple classes of gamma-ray bursts, as deduced from autocorrelation functions or bivariate duration/hardness ratio distributions
Autocorrelation functions (ACFs) of 119 gamma-ray bursts (GRBs) monitored by the Burst
Alert Telescope (BAT) on Swift are calculated. Contrasting with previous results for smaller
numbers of bursts from other missions, the widths of the ACFs are not bimodally distributed.
Although the distribution appears slightly asymmetrical, underlying mixtures of distributions
can also probably be ruled out. Factors contributing to differences between the results presented
here, and those in the literature, may include the differences in energy passbands used, and
the superior sensitivity of the BAT instrument (which affects e.g. the redshift distribution of
the detected GRB). The second part of the paper is concerned with the fitting of mixtures of
bivariate Gaussians to the joint duration/hardness ratio data of 325 GRBs. A careful analysis
confirms that a three-component mixture is the statistically most acceptable, but it is shown
that the implied marginal distribution of the hardness ratios does not fit the data very well.
It is also stressed that mixture components cannot automatically be assumed to represent
different classes of GRBs. The point is illustrated by showing two substantially different, but
statistically almost equivalent, mixture models for the distribution of 571 BAT-determined
GRB durations.Web of Scienc
Test-retest reliability of a new self reported comprehensive questionnaire measuring frequencies of different modes of adolescents commuting to school and their parents commuting to work - the ATN questionnaire
<p>Abstract</p> <p>Background</p> <p>Studies assessing active commuting to school usually use simple questionnaires, and often is mode of commuting reported with a single questionnaire item only. The purpose of the present study is to report the test-retest reliability of a newly developed comprehensive questionnaire on active commuting to school and work among 6<sup>th </sup>grade school children and their parents in Norway.</p> <p>Methods</p> <p>A total of 106 pupils and 77 parents completed a questionnaire two times, 14 days apart. The questionnaire consisted of frequency items on how often the participants walk, cycle, go by car and go by public transportation to school (pupils) or work (parents). The questionnaire was divided into seasons and to/from school or work in order to cover seasonal and topographic variations. The average number of trips for each mode of commuting was calculated. Then the sample was categorised into mode of commuting: walkers, cyclists, car commuters or public transport commuters.</p> <p>Results</p> <p>The average numbers of trips did not differ for any of the commuting modes comparing test to retest data for any of the seasons. Test-retest correlation coefficients were high for all modes of commuting (Spearman correlation coefficient were 0.85-0.92 for pupils and 0.82-0.95 for parents). Most participants categorised into mode of commuting were categorized into the same mode at both time points (97% and 95% for pupils and parents respectively).</p> <p>Conclusion</p> <p>This newly developed questionnaire appears to be a reliable tool for measuring active commuting to school and work.</p
Identification of Features from User Opinions using Domain Relevance
Identification of opinion features from online user reviews is a task to identify on which feature user is going to put his opinion. There are number of existing techniques for opinion feature identification but, they are extracting features from a single corpus [2]. These techniques ignore the non trivial disparities in distribution of words of opinion features across two or more corpora. This work discusses a novel method for opinion feature identification from online reviews by evaluation of frequencies in two corpora, one is domain-specific and other is domain-independent corpus. This distribution is measured by using domain relevance [12]. The first task of this work is the identify candidate features in user reviews by applying a set of syntactic rules. The second step is to measure intrinsic-domain relevance and extrinsic-domain relevance scores on the domain dependent and domain-independent corpora respectively. The third step is to extract candidate features that are less generic and more domain specific, are then conformed as opinion features. This approach is called as intrinsic extrinsic domain relevance.
DOI: 10.17762/ijritcc2321-8169.150611
Analisis Performansi Turbin Angin Poros Horisontal Model Double Rotor Contra Rotating Dengan Posisi Rotor Saling Berhimpitan
The contra rotating wind turbine is a horizontal axis turbine which has two shaft rotating in opposite directions on the same axis, and it can work at low wind speeds. In general, the performance of the wind turbine are affected by several factors, which is the aerodynamics shape of turbine, the numbers of blade and the selection angle of blade. In this study, conducted by determining the variation of angle on the blade and the blade angle used in the study is 0o, 5o, and 10o, on the two rotors with diameter of front rotor is 0.50 meters and the rear rotor is 0.30 meters, with the position of the rotor blade is coincident with each other. The purpose of this study, is to determine the effect of blade angle variation on the turbine rotation (rpm), torque (T), the power coefficient (Cp), torque coefficient (Cq) and the efficient of the turbine at any wind speeds variations. On the graph relation of blade angle on the shaft rotation, turbine rotation riding known to along with the addition of angle of the blade. The speed of wind is very affect on the output or mechanical power and power coefficient. On the blade angle 0o with wind speed at 4.03 m/s, the power can be generate is 3.013 Watt, and for blade angle 10o with wind speeds 6.08 m/s, the power can be generate is 8.217 Watt. The lowest rotation of rotor without loading is 702 rpm at the wind speeds on 4.03 m/s with angle of blade 0o, the highest rotation of rotor is 1484 rpm on the wind speeds 6.08 m/s with angle of blade 10o. From the graph of analysis data can be seen , with change of angle blade on wind turbine horizontal shaft contra rotating models, power coefficient (Cp) generated of turbine activity increases with increased of angle, with Cp maks 0.718 for angle 10o, maximum efficiency an generated reach out 71.8
Faktor Risiko Kejadian Pre-eklamsia pada Ibu Hamil di Kabupaten Belu
Pre-eklamsia merupakan suatu keadaan patologi yang ditandai dengan adanya hipertensi, proteinuria dan edema. Penelitian ini bertujuan untuk menganalisis faktor risiko dengan kejadian pre-eklamsia pada ibu hamil di Kabupaten Belu. Jenis penelitian yang digunakan adalah penelitian retrospektif dengan desain case control dan menggunakan pendekatan kuantitatif dan kualitatif. Penelitian ini dilaksanakan pada wilayah kerjaPuskesmas di Kabupaten Belu, periode Januari–Maret 2015. Analisis statistik yang digunakan adalah chi-square dan Odd Ratio. Besar sampel kasus 40 ibu dan kontrol 40 ibu yang diambil dengan teknik purposivesampling. Hasil penelitian ini ditemukan adanya hubungan yang signifikan antara faktor risiko umur (p=0,007;OR=0,286;95%CI=0,133-0,721), paritas (p=0,014;OR-0,323;95%CI=0,130-0,804), riwayat hipertensi(p=0,007;OR=3,462;95% CI=1,379-8,691), riwayat pre-eklamsia (p=0,000;OR=2,379;95% CI=1,803-3,139), antenatal care (p=0,000;OR=0,140;95%CI=0,052-0,378) terhadap kejadian preeklamsia. Variabel yang mempunyai risiko terjadinya pre-eklamsia adalah riwayat hipertensi mempunyai risiko 3 kali, riwayat pre-eklamsiamempunyai risiko 2 kali sedangkan variabel umur, paritas dan pemeriksaan kehamilan (ANC) merupakan faktor protektif
PENGARUH PERBEDAAN KECEPATAN PUTARAN MESIN (RPM) TERHADAP KINERJA MESIN PENCACAH LIMBAH JAGUNG UNTUK PAKAN TERNAK SAPI DI NUSA TENGGARA TIMUR
Penelitian ini bertujuan untuk mengetahui pengaruh kecepatan putaran mesin pencacah terhadap kualitas hasil cacahan dan menentukan kecepatan putaran mesin dengan hasil cacahan yang berkualitas. Metode yang digunakan dalam penelitian ini adalah metode ekperimental untuk menganalisis ragam pengaruh perlakuan terhadap pengaruh perbedaan kecepatan putaran mesin. Dengan metode ini dapat menganalisis dan diketahui perlakuan terbaik. Hasil penelitian menunjukkan bahwa kapasitas kerja tertinggi terdapat pada RPM 3400 sebesar 13,11 gr/menit yang berbeda nyata dengan perlakuan lainnya. Kapasitas kerja alat terbaik terdapat pada perlakuan C dengan nilai rata rata sebesar 5,43 gram/menit. Hasil uji jarak berganda duncan terhadap keseragaman hasil cacahan menunjukkan bahwa pada pada kecepatan putaran 3400 rpm menghasilkan ukuran cacahan terbaik dengan ukuran 2 cm paling besar yaitu sebanyak 5,43 gram, yang berbeda nyata dengan kecepatan putaran mesin lainnya
Do children\u27s food preferences align with dietary recommendations?
Objectives: To examine how Australian children\u27s reported everyday food preferences reflect dietary recommendations, and the impact of sociodemographic factors on these associations.Design: Cross-sectional survey.Setting/subjects: Three hundred and seventy-one parents of children aged 2–5 years, recruited from three socio-economic groups in two Australian cities, completed a survey on their child\u27s liking for 176 foods and drinks on a 5-point Likert scale in addition to demographic descriptors. Preferences were compared with the recommendations of the Dietary Guidelines for Children and Adolescents in Australia and the Australian Guide to Healthy Eating.Results: Foods in the Extra Foods (non-nutritious foods) and Cereals groups of the Australian Guide to Healthy Eating were highly liked (mean: 4.02 and 4.01, respectively), whilst foods in the Vegetables group were liked least (mean: 3.01). A large percentage of foods in the Cereals and Extra Foods groups were liked (64% and 56%, respectively) in contrast to the other food groups, especially Vegetables (7%). Children liked foods that were higher in sugar (r = 0.29, P < 0.0001) and more energy-dense (r = 0.34, P < 0.0001) but not those higher in saturated fat (r = 0.16, P = 0.03), total fat (r = 0.12, P = 0.12) or sodium (r = 0.10, P = 0.18). Sociodemographic variables (e.g. socio-economic status, parental education, children\u27s age and sex) explained little of the variation in children\u27s food preferences.Conclusions: Australian pre-school children\u27s food preferences align with dietary guidelines in some respects, but not others. Interventions are needed to shift children\u27s preferences away from non-nutritious foods that are high in energy density and sugar, and towards vegetables and fruits.<br /
The monitored performance of the first new London dwelling certified to the Passive House standard
The monitored performance of the first new London dwelling certified to the Passive House standard is presented. The first detailed analysis of the energy consumption of the heating, ventilation and domestic hot water systems are given. The annual space heating demand of the 2 bedroom, 101 m2 dwelling was 12.1 kWh/m2, achieving the 15 kWh/m2 Passive House target. The annual primary energy demand was 125kWh/m2, marginally above the 120 kWh/m2 target. The measured internal heat gains of 3.65 W/m2 are much greater than the 2.1 W/m2 suggested as standard for dwellings. The Passive House Planning Package, PHPP, is found to be a good predictor of space heating demand and the risk of summer time over heating. Winter space heating demand is sensitive to occupant blind use. With a total metered energy consumption of 65 kWh/m2, the Camden Passive House is one of the lowest energy, small family dwellings, monitored in the UK
Preparation of Biomass-Derived Furfuryl Acetals by Transacetalization Reactions Catalyzed by Nanoporous Aluminosilicates
Nanoporous aluminosilicate materials efficiently catalyze the formation of furaldehyde dimethyl acetal directly from methanol in high yields and in short reaction times. The facile nature of this reaction has led to the development of a telescoped protocol in which the acyclic acetal is produced in situ and subsequently functions as a substrate for a transacetalization reaction with glycerol to produce the corresponding dioxane and dioxolane products, which are potentially useful biofuel additives. These products are generated in high yield without the requirement for high reaction temperatures of prolonged reaction times, and the aluminosilicate catalysts are operationally simple to produce, are effective with either purified furaldehyde or crude furaldehyde, and are fully recyclable
- …