Miracle-dz/UniFAR-FTUs huggingface dataset:
Digital storytelling as a tool for teaching: Perceptions of pre-service teachers

It has been shown that teachers are reluctant to use technology despite the South African (SA) government’s huge expenditure on technological equipment. This might be the result of teachers being unable to select appropriate technology that will yield positive learning outcomes as well as being ill-equipped to integrate technology into their pedagogy. To this end, pre-service teachers at a University were trained on how to integrate digital storytelling (DST) effectively into their teaching. The aim of this study is to gain insight into the potential benefits of DST for teaching and learning and to determine factors that may prevent pre-service teachers’ uptake of DST during in-service practice. This is a qualitative study in which fifty pre-service teachers were divided into five groups for focus group interviews. Data were analysed, and the results show that pre- service teachers perceived DST to be beneficial in the classroom as it has the potential to (i) motivate and engage learners, (ii) promote voice/self-expression, and (iii) promote collaborative learning and acquisition of multiple skills. Pre-service teachers are of the opinion that a lack of resources, self-confidence and time owing to restrictive curricula may prevent uptake of DST during in-service teaching. It was recommended that school stakeholders create a balance between intrinsic and extrinsic factors that will promote the adoption and integration of DST into teaching. Also, the education institution concerned strives to balance all three strands of knowledge: technology, pedagogy and content.
A review of para-professional engineering education in Australia: exploring the VET-HE divide

The differences between the Vocational Education and Training (VET) and higher education (HE) sectors have been well documented over recent years, often in the context of the impact those differences have on student movement between sectors. In engineering, the differences between the sectors are exemplified by the different approaches each sector takes to para-professional education. Both VET sector Advanced Diplomas and HE sector Associate Degrees are Level 6 qualifications under the Australian Qualifications Framework, and are designed to educate para-professional Engineers. This paper describes some of the key features of the engineering programs offered in each sector and explores the differences between them. It then discusses the implications of those differences on student learning and student movement between the sectors. The final section describes some key changes occurring in the tertiary education sector and the impact they may have on para-professional engineering education.
Extraction and Characterization of Nanocellulose from Eragrostis Teff Straw

This work presents the extraction and characterization of nanocellulose from agricultural waste (Eragrostis Teff) straw. The proximate analysis of the straw was done with three triplicates and the average value was recorded. The moisture, ash, volatile matter, and fixed carbon content were 6.4%, 5.1%, 74.2%, and 15.6%, respectively. The extractives, lignin, hemicellulose, and cellulose content were found to be 8.5%, 17.5%, 29.5%, 36.5%, respectively. The cellulose was extracted from teff straw by hot water treatment, acid-chlorite delignification, and alkaline hydrolysis process respectively. The values of process parameters such as temperature, time, and sodium hydroxide concentration for alkaline hydrolysis were 57.6 \(℃\) , 1hour, and 4(w/v) % respectively to obtain a cellulose yield of 78.7%. The nano cellulose particles were extracted from the cellulose by acid hydrolysis process (48%v/v sulfuric acid) at 35\(℃\) for 30 min and the yield was 42.8%. The characterization of nano cellulose was done by using Fourier-transform infrared spectroscopy, dynamic light scattering, x-ray diffraction, and thermogravimetry analysis/ derivative thermogravimetry analysis to determine the functional group, particle size distribution, crystallinity, and thermal stability respectively. The Fourier-transform infrared spectroscopy result shows that the reduction and total removal of lignin, hemicellulose, and other amorphous parts found in teff straw. The average particle size was found to be 101.6 nm with a polydispersity index of 0.047. The crystallinity index of teff straw and nano cellulose was 47.7 and 77.1% respectively. The thermogravimetry analysis shows the thermal stability of the nanocellulose sample was lower than that of cellulose and teff straw samples.
Two cylindrical obstacles in a rectangular waveguide-resonances and filter applications

Two metallic or lossy dielectric cylinders placed in one cross section of a rectangular waveguide are investigated by the orthogonal expansion method. Resonances are shown by frequency responses of the transmission coefficient. They are discussed by patterns of the magnetic field and diagrams of the Poynting vector. Physical explanations of the resonances are given. The structure may be used as a filter element. With two small dielectric posts, a frequency characteristic with two stopbands can be obtained. Center frequencies are tunable by moving the posts. Using one large metallic and one small dielectric post, a tunable passband characteristic can be realized. >
Progressive collapse vulnerability in 6-Story RC symmetric and asymmetric buildings under earthquake loads

Progressive collapse, which is referred to as the collapse of the entire building under local damages, is a common failure mode happened by earthquakes. The collapse process highly depends on the whole structural system. Since, asymmetry of the building plan leads to the local damage concentration; it may intensify the progressive collapse mechanism of asymmetric buildings. In this research the progressive collapse of regular and irregular 6-story RC ordinary moment resisting frame buildings are studied in the presence of the earthquake loads. Collapse process and collapse propagation are investigated using nonlinear time history analyses (NLTHA) in buildings with 5%, 15% and 25% mass asymmetry with respect to the number of collapsed hinges and story drifts criteria. Results show that increasing the value of mass eccentricity makes the asymmetric buildings become unstable earlier and in the early stages with lower number of the collapsed hinges. So, with increasing the mass eccentricity in building, instability and collapse of the entire building occurs earlier, with lower potential of the progressive collapse. It is also demonstrated that with increasing the mass asymmetry the decreasing trend of the number of collapsed beam and column hinges is approximately similar to the decreasing trend in the average story drifts of the mass centers and stiff edges. So, as an alternative to a much difficult-to-calculate local response parameter of the number of collapsed hinges, the story drift, as a global response parameter, measures the potential of progressive collapse more easily.
Thermoelastic Stress Analysis of T-Stub Model

Thermoelastic Stress Analysis (TSA) has been used to obtain the stress field in bolted T-Stub joint models (as defined by Eurocode 3) subject to cyclic loading which were employed to validate a Finite Element (FE) model. It was concluded from the results of the experiments and modeling that the behavior of the T-Stub is more complex than claimed by Eurocode due to contact forces, bolt interaction and plastic behavior.
The Unfinished Revolution: Human-Centered Computers and What They Can Do for Us

From the Publisher: Using a computer ought to be as easy and productive as driving your car. But today's systems are oblivious to our needs and demand ever more attention and work from us, as they swell in numbers, complexity and features. now Michael Dertouzos argues that we must shift the focus of information technology away from machines and back to people. In The Unfinished Revolution, he not only outlines five key technologies that will help us do this, he also offers and exciting vision of how human-centric computers could dramatically alter the way we live and work in the Information Century. About the Author: For more than a quarter century, Michael Dertouzos has headed up the MIT Laboratory for Computer Science, which has been associated with many of the most important developments in computing. Dertouzos is the author of the 1997 best-seller What Will Be: How the New World of Information Will Change Our Lives. He lives in Weston, MA.
The Reengineering Alternative: A Plan for Making Your Current Culture Work

Organizations can hire consultants and purchase expensive training programmes - but improvement must still be generated from within. "The Reengineering Alternative" explains how organizations can develop effective improvement plans based upon their unique strengths and corporate objectives. This book should prove valuable to managers who recognize the need for organizational change, but either haven't found an appropriate improvement programme, or can't fit an outside programme into the budget. The book provides a questionnaire readers can use to determine causes of conflict and sources of competitive strength. It demonstrates effective management and helps readers make the most cost-effective decisions concerning change and improvement within their organization.
On the Feasibility of Shearographic Imaging of Acoustic Cross‐Modulation

Abstract: The detectability of defects as well as their detection contrast have significantly increased in recent years because of the use of nonlinear variants of the classical non‐destructive acoustic methods. The non‐uniformity of stiffness and hysteresis around the area of a defect results in strong non‐classical acoustic nonlinearity, which can be used to effectively distinguish the presence of defects. Motivated by the latest advances in nonlinear laser Doppler vibrometry and nonlinear ultrasonics, we investigated the potential of shearography to detect the so‐called cross‐modulation effect. This effect arises when a strong, low‐frequency pump wave dynamically changes the elastic response of a defect, so that the amplitude of a weak, high‐frequency probing wave passing through the defect is modulated. As a result, the frequency spectrum of the response contains mixed frequency components, which are directly attributed to the underlying defect.
Weight Analysis of Two-Stage-To-Orbit Reusable Launch Vehicles for Military Applications

Abstract : In response to Department of Defense (DoD) requirements for responsive and low-cost space access, this design study provides an objective empty weight analysis of potential reusable launch vehicle (RLV) configurations. Each two-stage-to-orbit (TSTO) RLV has a fixed payload requirement of 20,000 lbf to low Earth orbit. The propulsion systems considered in this study include pure rocket, pure turbine, rocket-based-combined-cycle (RBCC), and turbine-based-combined-cycle (TBCC). The hydrocarbon dual-mode scramjet (DMSJ) engines used in the RBCC and TBCC propulsion systems represent possible applications of the current research being performed in the U.S. Air Force HyTech program. Two sensitivity analyses were then performed on areas of interest directly affecting the propulsion systems in this study, including the effects of orbiter fuel selection, as well as the effects of increasing the turbine installed thrust to weight ratios for the RLVs utilizing afterburning turbine engines. The vertical-takeoff-horizontal-landing (VTHL) RLVs have an empty weight advantage over the horizontal-takeoff-horizontal-landing (HTHL) RLVs. The orbiter propellant switch has either negligible or no empty weight savings for the VTHL RLVs, while it leads to substantial empty weight savings for the HTHL RLVs. For the HTHL RLVs, increasing the turbine installed thrust to weight ratio causes a significant decrease in empty weight.
Characterization of High Power Pseudospark Plasma Switch (PSS)

The Pseudospark switch is able to control high voltage and high current discharges and operates at low pressure like Thyratron but much simpler in construction and does not suffer in electrodes wear. This switch is bipolar and has 100 % reverse current capability, much faster than Thyratron and has applications in pulse power modulators, linear accelerators, laser systems etc. Such switch has been developed at CEERI Pilani and tested in a demountable setup. For this switch, as a cold cathode based ferroelectric trigger source has also been developed and characterized. High dielectric material has been opted for such a source. The hold off voltage can be doubled if the gap of the electrodes is stacked to two single stage gaps. Such stack of two single stage switches has also been fabricated in a demountable setup. Switching behavior has been observed up to 23 kV and 7 kA in single stage. High voltage conditioning and characterization is still in progress. The paper includes the introduction with working principle, description of the demountable set up, simulation by TriComp, AMaze and OOPIC Pro (Without Comparison among them), and switching behavior.
Operation of an on-line substation diagnosis system

An online monitoring system applied to a recently built substation is described. It monitors the 204 kV and 72 kV gas-insulated switchgear and the transformer in their normal operating condition. The basic principle used to detect an abnormality is presented together with a record of the system's operation in the first year. >
Commercial Driver Factors in Run-off-Road Crashes

The number of commercial vehicles on U.S. roads has grown dramatically over the past few decades. Although the number of large trucks involved in fatal and injury crashes has decreased over the past 20 years, large trucks still have a higher fatal crash involvement rate than passenger cars do. This study sought to gain insights on the impact of commercial driver factors on crash severity with respect to single-vehicle, run-off-road (ROR) crashes. A logistic model was conducted with large truck crash data from the Washington State Department of Transportation (years 2006 to 2009). The model predicted the effects of truck driver distraction, inattention, speeding, seat belt usage, and drowsiness and fatigue on the likelihood of an ROR crash involving injury or fatality. Other factors, such as environmental conditions, roadway types, and truck-related factors, were controlled in the model. Results indicated that speeding, drowsiness and fatigue, and distraction and inattention strongly affected increasing crash severity. As expected, seat belt use significantly decreased the severity of an ROR crash. The study confirms that several driver factors observed in other studies on crash likelihood are also significant for ROR crashes involving large trucks.
Estimation of land-based emissions during container terminal operations in the Ambarlı Port, Turkey

Many types of mobile vehicles are used simultaneously in container terminal operations. Because most of these mobile vehicles have diesel engines, they emit a significant amount of pollutant emissions into the atmosphere during their operation. They are considered as land-based mobile emission sources (MobES) and should be included in the total port emission inventory. The emission inventory is a basic requirement in developing an environmental management strategy to improve emission control. In this context, this study aims to estimate the emission inventories of mobile vehicles used in terminal operations in the Ambarlı container ports located in the city of Istanbul, which is one of the most populous cities in the world. In this respect, the amounts of the emissions of all the container handling equipment with diesel engines in the port areas, including external trucks delivering/receiving containers to/from the port were estimated using an activity-based method. It has been found that approximately 42.39% of the total CO2 emission is owing to terminal tractors and the total annual CO2 value per TEU (Twenty-foot Equivalent Unit) of MobES is 0.01259 tons. The CO2 value per TEU can serve as a CO2 emission performance indicator for land-based MobES in process of the evaluation of emission inventories in container ports.
Teaching/Learning Architectural Design based on a Virtual Learning Environment

This paper describes an experiment in which a virtual learning environment was used in the context of an architectural design course. The objective was to evaluate the capability of the learning environment used to support the interactions needed, between teacher-student and between students, for the establishment of a process of discussion and development of architectural design. Some limitations were identified and also positive points, such as the possibility to register the whole design process. These registers allow the design teacher to evaluate his own teaching process and improve it and also the visualization of what kind of intervention the teacher makes and when, making it possible to identify the kind of design processes established by the student and the kind of structure of knowledge which is implicit in a process of teaching/learning architectural design according to the level of development of the design.
EQUILIBRIUM CHARACTERISTICS OF AXIAL GROOVE GAS LUBRICATED BEARINGS.

Abstract : The report contains the description of a new general method for the solution of Reynold's equation for compressible and incompressible lubrication. A great improvement in numerical stability and speed of convergence is derived for all fluid film geometries including converging-diverging ones. The method is used for the determination of load coefficients and attitude angles of three- and four-pad axial groove cylindrical bearings. (Author)
Intermodal Transfer between Bicycles and Rail Transit in Shanghai, China

Large cities in China are building rail transit systems as part of a key strategy to address their pressing urban transportation problems. Because the high construction cost of subways and light rail limits the network density of rail transit, urban transport planners must seek effective intermodal connections between rail and other modes. This research examines the challenges and opportunities for improving the bicycle–rail connection by using Shanghai as a case study. On the basis of two questionnaire surveys of rail transit riders, the research analyzes the existing mode shares of rail station access and egress trips, the underlying mechanisms for choosing among alternative modes, and the comparative advantages of the bicycle for trips that have certain distance and location characteristics. Empirical results suggest that the potential for travel improvement for rail transit riders lies primarily in the collection and distribution phases. Results point to several promising approaches to improving the bicycle–rail connection and utilizing the bicycle more fully as an efficient supplement mode for the rapidly expanding urban rail transportation in China. In addition, the work can be a useful reference for cities in other countries in which rail transit development is accompanied by the continued importance of bicycles in residents’ travel.
An evaluation of red light camera (photo-red) enforcement programs in Virginia : a report in response to a request by Virginia's Secretary of Transportation.

Red light running, which is defined as the act of a motorist entering an intersection after the traffic signal has turned red, caused almost 5,000 crashes in Virginia in 2003, resulting in at least 18 deaths and more than 3,800 injuries. In response to a June 2, 2004, directive from Virginia Secretary of Transportation Whittington W. Clement, an evaluation of the photo-red enforcement programs that operate in Virginia was undertaken. Generally, Virginia's photo-red programs are technically feasible. Case law strongly indicates that the programs pass legal muster in the three key areas: privacy, equal protection, and due process, and public opinion surveys suggest that roughly two-thirds of respondents support red light cameras. There is, however, a practical issue with regard to issuing citations for out-of-state motorists, as noted in the report. Although an economic analysis was not feasible in the study time frame, a limited fiscal analysis suggests that, in general, Virginia localities are not generating net revenue. Finally, an operational analysis based on violations and crashes shows a potential but not definite safety improvement. The cameras clearly affect driver behavior; across the 23 intersections where reliable citation data could be obtained, citations decreased by an average of 21% per intersection. Further the data show that the cameras are correlated with a definite decrease in crashes that are directly attributable to red light running, a definite increase in rear-end crashes, a possible decrease in angle crashes, a net decrease in injury crashes attributable to red light running, and an increase in total injury crashes. More time is needed to determine whether the severity of the eliminated red light running crashes was greater than that of the induced rear-end crashes. The report recommends that Virginia's photo-red enforcement programs be continued for an additional year to resolve this question and to collect additional data that was not feasible during the 6-month time frame of this report.
Nonlinear phenomena in DC–DC buck converter by means of iteration mapping technique

In this paper, the nonlinear phenomenon in DC/DC buck converter is studied. A practical design for a DC/DC buck converter was considered in this study, which results in a more comprehensive understanding for the phenomenon. The nonlinearity of the buck converter is studied using the iteration mapping technique. The results showed that if the system has a well–designed buck converter as well as a feedback controller, then it does not exhibit any nonlinear behaviour. To verify these results, a buck converter, with non–practical parameters, was also studied. In this case, the results showed bifurcation and then chaotic behaviour for the output voltage and inductor current as the input voltage changes. A comparison between the two cases is discussed in more details.
ON DIFFERENT FE-BASED MODELS TO SIMULATE CUTTING OPERATION OF TITANIUM ALLOY (TI-6AL-4V)

Finite element based models for cutting operation present outstanding complexities due to their nonlinear and multi-physics coupling. Nevertheless, there is no uniform standard for the comparison between cutting simulation models based on different software. The present work deals with various methodologies to simulate orthogonal cutting operation for Ti-6Al-4V Titanium alloy inside two commercial codes: ABAQUS and DEFORM. The aim is to show how considered optimal FE numerical approaches can imply agreements or disparities in outputs between the two pre-cited codes. In order to carry out a comparative study between the two codes, similar conditions concerning geometrical models and cutting parameters were adopted. A multi-physic comprehension related to chip formation, cutting forces, temperature evolutions, and surface integrity was presented. Moreover, the numerical results were compared with experimental ones for a deeper discussion on numerical predictions, and problems with current simulation were addressed to improve and support process innovations. DOI: http://dx.doi. org/10.5755/j01.mech. 19.3. 4656
Design and fabrication of an erectable truss for precision segmented reflector application

The design of a first generation, 4-meter-diameter, doubly-curved, tetrahedral support truss for precision parabolic reflector panels, incorporating joints specifically designed for on-orbit astronaut assembly, is presented. Operational and design features of the erectable joint are detailed. Methods used to achieve very accurate strut lengths are described. Initial static and dynamic truss test results are presented which demonstrate linear structural response and predictability. Truss surface accuracy, determined photogrammetrically, is shown to be within 0.003 inch (RMS) of design.