Miracle-dz/UniFAR-FTUs huggingface dataset:
METHODS FOR STIMULATION OF ACTIVE LEARNING IN STUDENTS

In pedagogical practice as a whole there is a growing tendency of employing methods and means that stimulate and activate students to learn during the training process and to enhance their cognitive and professional competencies. An empiric study has been conducted, to discuss and analyze the level of assessment made by students, on methods for active learning stimulation. A survey has been conducted among students studying in two professional orientations. An assessment card has been developed, with main question “Lecturers stimulate active learning of students by using predominantly the following training methods”, structured in two main parts: a) assessment of methods used by the lecturers in the process of training (from 2 to 6 ascending index scale); b) lecturers create conditions for active learning of students by providing opportunity for students to ask questions; give freedom for sharing own ratiocinations; use multimedia devices; include examples from practice; relate the problem to students’ future profession; use various means and techniques (three-index responsive scale: 1 – never, 2 – sometimes, 3 – always). Scope of survey - 102 students from the Medical college at the Medical University of Pleven, from two departments - Health Care (N = 45) and Social Activities (N=57) who have participated voluntarily. The data from the survey for the first part of the question have been analyzed for each department and for the second part the total results from the survey among students from both professional orientations have been shown. Relative rate of highest index responses only are displayed in tables, as they use the highest index and show most determined, explicit choice. The three units subject to analysis, with highest rate of assessment of training methods employed by lecturers, marked by the respondents from Health Care Department are: Seminars -77,78%, Laboratory and Practice - 76,56%, Lectures - 62,22%; results for respondents from Social Activities Department: Case Solving - 68,42%; Lecture, Game Method, Situational Method - 66,68%; Project Method - 56,14%. Regarding the methods for activation of students attitude during the training process the first three places of highest absolute rate of units of analysis, the respondents determine “opportunity for students to ask questions”- 85,29%; “freedom for sharing own ratiocinations” - 82,35%; “using multimedia devices” - 79,41%. The employed methods of training define the main frame for the learning process and support the subject-subjective pedagogical interactions between lecturers and students, for achieving specific educational objects and stimulation the activity in mastering professional knowledge, for creation of a real relation between training and practice. In the training process the lecturers stimulate students’ active attitude by creating conditions for searching answers to various issues, for free expression of opinions and self-development of future specialists.
Low-cycle fatigue testing of silicon resonators

This paper presents a testing methodology for measuring the low cycle fatigue properties of single-crystal silicon thin films using kHz-frequency resonators. The dynamic behavior of the fatigue structures is thoroughly characterized to allow accurate measurements of stresses (±0.1 GPa) and fatigue lives (±250 cycles). The tests consist of applying successive bursts of small numbers of cycles (as low as ~500 cycles) and measuring the resonant frequency in between each burst. Continuous damage accumulation, beginning after the first burst, is observed based on the decrease in resonant frequency of the resonant structure.
Smart mouse: 5-DOF haptic hand master using magneto-rheological fluid actuators

This paper is concerned with a haptic hand master intended to display force feedback at the fingertip of the human user. The haptic hand master, named 'Smart Mouse' has two significant differences from previous other hand masters: actuators and structure. Five passive actuators featured with magneto-rheological fluid are used to ensure the interface safety and the control stability. In order to eliminate the unnecessary reaction force and reduce muscular fatigue during operating, the mouse-like structure is adapted. Also, two assumptions are proposed for the simplicity of its kinematics and manufacturing; one is that the fingertips lies on a plane during grasping the objects, and the other is that the equilibrium point of the fingertip reaction forces is in the object. Due to these characteristics, the human hand operating the smart mouse has the kinematic configuration similar to a 5-DOF parallel manipulator.
The Theory Investigation for the Antioxidant Activity of Phloretin: A Comparation with Naringenin

Density functional theory (DFT) calculations, based on B3LYP/6-311G (d, p) basis set, were performed to evaluate the OH bond dissociation energies (BDEs) for phloretin, compared with naringenin, in order to assess the contribution of hydroxyl groups at different position to the radical-scavenging properties. It is indicated clearly that A6 OH is determined as the weakest O-H bond, give rise to the smallest BDE, 73.98 kcal/mol. BDE of B4 OH decreases 2.5 kcal/mol in benzene, very close to that of A6OH, indicated that B4 OH group is also mainly contributed to the reaction with free radicals, especially in non-polar environments.
Determining the Green-Ampt Effective Hydraulic Conductivity from Rainfall-runoff Data for the WEPP Model

The Green-Ampt infiltration equation is used in many different hydrologic models. The effective hydraulic conductivity parameter (Ke) within this equation is needed to obtain reliable estimates of infiltration and runoff. In this study, a method was developed for calibrating Ke for the Green-Ampt equation as integrated with the WEPP continuous simulation model using a series of rainfall-runoff events on natural runoff plots. Optimum values of Ke were obtained at seven locations, and the average Nash-Sutcliffe model efficiency for the Green-Ampt/WEPP predictions of runoff on an event basis was 0.46 using these Ke values. Green-Ampt/WEPP tended to overpredict runoff on the small events and underpredict runoff on the larger events. This bias could not be corrected through calibration and indicates a structural flaw in the Green-Ampt equation, the WEPP model, or the available data. Other estimates of effective hydraulic conductivity were obtained from five different parameter estimation methods based on relationships involving common soil properties and were used in the Green-Ampt/WEPP model to predict runoff at each of the locations. None of these methods of estimating the effective hydraulic conductivity consistently outperformed the others for all the data sets. The average Nash-Sutcliffe model efficiency obtained using the best estimated parameters was –0.16, indicating that considerable improvement was obtained with calibration.
Piezo-Actuated Microtensile Test Apparatus

The design and performance of a microtensile test device designed for measuring the mechanical properties of thin films are reported. The moving grip is cantilevered to avoid friction. Piezoelectric actuation allows precise control of the applied tension. Force is measured indirectly using an eddy-current sensor near a flexible measuring beam, and grip displacement is measured using two similar displacement sensors. The apparatus is constructed for use with specially designed specimen assemblies in which the thin film to be tested is suspended across a silicon frame. The apparatus is rigid enough that the frames can be cut without applying tension to the thin-film tensile specimen. The tester is run in closed-loop control through a laboratory computer, which records force, displacement, and other parameters 5 times per second. Key capabilities are: stroke, 50 μm; maximum force, 1 N; minimum cycle time, 2 s; displacement resolution, ± 20 nm; and force resolution, ± 200 μN.
Neural Classifiers for Automated Visual Inspection

This paper discusses the application of a back-propagation multi-layer perceptron and a learning vector quantization network to the classification of defects in valve stem seals for car engines. Both networks were trained with vectors containing descriptive attributes of known flaws. These attribute vectors (‘signatures’) were extracted from images of the seals captured by an industrial vision system. The paper describes the hardware and techniques used and the results obtained.
Study of the lower limp's angle during weightlifting exercises using an accelerometer-based system

This article describes the implementation and use of a two-accelerometer system to measure the angle formed between lower joints of weightlifters during the execution of the technical gesture. Being aware of movement between joints will allow identifying bad moves and prevent injuries in athletes. Likewise, it will help in turn to rehabilitation for people with problems in the movement of their joints. This design is based on open platforms both hardware and software. The preliminary result shows that we can connect a two-accelerometer system with an error in the measure of the angle no greater than 1.3% (0.795% on average).
Characterization of frequency-selective surface spatial filters in a rectangular waveguide

The possibility to characterize infinite and periodic frequency-selective surfaces (FSS) filters that have two orthogonal axes of symmetry inside a waveguide is reported. Thus, preliminary measurements can rapidly be obtained at low cost with few elementary cells instead of using a large FSS panel in free space. This is possible because of the equivalence that exists between the electromagnetic fields of two symmetric and oblique plane waves incident on and reflected from an infinite periodic surface and the incident/reflected fields that exist inside a single-mode rectangular waveguide containing a finite number of elementary cells. Comparisons of the measurements with some full-wave simulations for FSS belonging to the first three groups as they were defined by Munk confirm the good agreement between them. This is an interesting and simple assessment tool concerning the fabrication quality of FSS. The extension of this technique to non-symmetric FSS patterns is also discussed and supported by experimental and simulation results. The limitations of the technique are finally discussed.
Microresonator array sensor

Microcavity optical resonators have been investigated in the last years extensively for possible applications in optical communication (switching, filtering, and multiplexing), to investigate cavity quantum dynamic effects, and for sensor applications. The most recent area of application is bio-sensing. The preferential resonator type in the communication area is the disc resonator, the spherical resonator is the most prominent resonator type in sensing applications and a rapidly growing number of groups are investigating the potential of hollow tube resonators for detecting of bio-agents. Here we will present the concept of resonator arrays as sensing element. Potential fields of application are similar to the single resonator sensor but also beyond. We will give an example of an application that is not accessible for single resonators. We will describe the use of resonator arrays as wavelength sensor and discuss several aspects such as the number of sensing elements or the line width on the performance of such a device.
Field-effect piezoresistors for vibration detection of nanobeams by using monolithically integrated MOS capacitors

A novel piezoresistive sensing method is presented herein for the detection of nanobeam resonator based on a monolithically integrated MOS (metal–oxide–semiconductor) capacitor structure. The bottom layer of the nanobeam located beneath the MOS capacitor is utilized as a piezoresistor for the detection of internal stress resulting from nanobeam deformation, and therefore the challenging process of ultra-shallow junction doping is avoided. When a bias voltage applied on the MOS gate exceeds the threshold, the depletion layer width is built up to the maximum, and the piezoresistive cancellation effect beside the neutral plane is eliminated. Based on a conventional microelectromechanical (MEMS) process, an MOS capacitor is fabricated at the terminal of a double-clamped nanobeam with dimensions of 46 µm × 7 µm × 149 nm. The measured R–V curve of this MOS structure presents a 64.7 nm thick piezoresistor which closely agrees with the design. This double-clamped nanobeam is excited into mechanical resonance by mounting it on a piezoelectric ceramic, and the amplitude–frequency response is measured by a network analyzer. The measured resonant frequency is 3.97 MHz and the quality (Q)-factor is 82 in atmosphere environment. Besides, this piezoresistive sensing method is verified by a laser-Doppler vibrometry.
A Parameter-Adjusting Autoregistration Imaging Algorithm for Video Synthetic Aperture Radar

Video synthetic aperture radar (ViSAR) is gaining increasing attention in the remote sensing area due to its advantages in continuous observation compared with conventional synthetic aperture radar (SAR). Generally, the polar format algorithm (PFA) is utilized to generate the ViSAR frames considering both processing efficiency and imaging quality. However, the changes in squint angles for different ViSAR frames will cause variations in target positions when the classic fixed-parameter PFA is utilized. Hence, an image registration step is typically needed, which greatly increases the computational load. Meanwhile, the azimuth resolution also deteriorates rapidly for the ViSAR frames as the squint angle becomes larger. In order to solve the aforementioned problems, a parameter-adjusting autoregistration PFA (PAAR-PFA) is proposed for the ViSAR. By adjusting system parameters, such as carrier frequency, pulsewidth, and sampling frequency, according to the azimuth sampling positions, PAAR-PFA can achieve autoregistration for ViSAR frames without range interpolation and geometric correction in fixed-parameter PFA, which significantly improves the processing efficiency. At the same time, since the azimuth sampling number of frame data is adjusted with the squint angle, the variation range of the azimuth resolution under different squint angles is considerably reduced. Point target and extended target simulations confirm the feasibility of the proposed algorithm.
Identification of Plant Parts Using Color and Geometric Image Data

An image-processing algorithm was developed that used color as well as geometric data to identify geranium cutting features such as petioles, main stem, leaf blades, and growing tip. The algorithm identified features independent of the orientation of the cuttings in the field of view. Cutting images were segmented into smaller objects which were classified according to geometric and 18-bit RGB color data. Correct pixel classification for leaf, petiole, and main stem material were 97, 95, and 93%, respectively. Some limitations observed were slow execution time (3 to 12 s) due to the volume of data accessed, misclassification due to the statistical color pixel classifier inadequately modeling the color space, and shadows causing improper segmentation.
Einsatz eines mobilen NMR‐Sensors als zerstörungsfreies Messsystem in der Bauwerkserhaltung

Das Potential der NMR‐MOUSE® als mobiles zerstörungsfreies Messsystem im Bereich der Bauwerkserhaltung wird anhand zweier Beispiele erläutert. Das erste Beispiel behandelt den Feuchtetransport in Feinbetonen während im zweiten die Bestimmung der Schichtdicken ausgewählter Oberflächenschutzsysteme dargestellt wird.
Risk assessment and management practices (RAMP) within the Tanzania construction industry: Implementation barriers and advocated solutions

Despite the extensive research on the barriers to the implementation of risk assessment and management practices (RAMP); there is a paucity of studies that examine these barriers within the context of developing countries, particularly Africa. This paper aims to investigate the perceptions of Tanzanian construction professionals concerning the barriers to the implementation of RAMP. A triangulated data collection approach is adopted. Barriers identified from literature review were empirically tested by data collected using a sample survey of 67 construction professionals drawn from 27 consultants; 24 contractors and 16 client organizations within the Tanzanian construction industry (TCI). Response data was subjected to descriptive and inferential statistics. Ranking and analysis of variance (ANOVA) were used to examine the barriers affecting the implementation of RAMP. These three listed barriers were identified as significant: (i) awareness of risk management processes; (ii) lack of experience; and (iii) lack of information. In contrast, ‘cost implementations’ and ‘time constraints’ were ranked lowly. The identified barriers could be used as a ‘road map’ for the development of appropriate solutions for successful implementation of RAMP, and to improve the decision-making processes of construction organizations. In addition, knowledge and understanding of risk management process would effectively contribute to identifying and managing inherent risk.
Additive manufacturing of lab-on-a-chip devices: promises and challenges

This work describes a preliminary investigation of commercially available 3D printing technologies for rapid prototyping and low volume fabrication of Lab-on-a-Chip devices. The main motivation of the work was to use off-the-shelf 3D printing methods in order to rapidly and inexpensively build microfluidic devices with complex geometric features and reduce the need to use clear room environment and conventional microfabrication techniques. Both multi-jet modelling (MJM) and stereolithography (SLA) processes were explored. MJM printed devices were fabricated using a HD3500+ (3D Systems) high-definition printer using a thermo-polymer VisiJet Crystal (3D Systems) substratum that allows for a z-axis resolution of 16 μm and 25 μm x-y accuracy. SLA printed devices were produced using a Viper Pro (3D Systems) stereolithography system using Watershed 11122XC (DSM Somos) and Dreve Fototec 7150 Clear (Dreve Otoplastik GmbH) resins which allow for a z-axis resolution of 50 μm and 25 μm x-y accuracy. Fabrication results compared favourably with other forms of rapid prototyping such as laser cut PMMA devices and PDMS moulded microfluidic devices of the same design. Both processes allowed for fabrication of monolithic, optically transparent devices with features in the 100 μm range requiring minimal post-processing. Optical polymer qualities following different post-processing methods were also tested in both brightfield and fluorescence imaging of transgenic zebrafish embryos. Finally, we show that only ethanol-treated Dreve Fototec 7150 Clear resign proved to be non-toxic to human cell lines and fish embryos in fish toxicity assays (FET) requiring further investigation of 3D printing materials.
Neural network analysis of pulp flow speed in low coherence Doppler flowmetry measurement

Low Coherence Doppler Flowmetry (LCDF) measurement produces a signal, which frequency domain characteristics are in connection to the speed of the flow. In this study a LCDF measurement data of pulp flow in a capillary was analyzed with a simple Artificial Neural Network (ANN) method to estimate the flow speed. The accuracy of the method proved to be good, validation of the method resulted in absolute error of 14 ± 11 percentage units (mean±std) in flow speed estimation. The results of the study can be utilized in development of industrial pulp flow speed measurement instruments.
A parametric study on flexible electro-active composites: Importance of geometry and matrix properties

Active fiber composites comprised of long circular fibers embedded in an epoxy polymer, where the fibers are made of the piezoelectric ceramic lead zirconate titanate. The active fiber composites use interdigitated electrodes, which produce electric field lines parallel to the fiber direction instead of through-the-thickness. It is noted, however, that the d33 of the active fiber composite is almost a third that of the lead zirconate titanate, mainly because of the significant mismatch in dielectric properties between the epoxy matrix and the ceramic fibers. The objective of the current work is to investigate the effects of active fiber composite geometry and polymer properties on the overall performance of active fiber composite in terms of mechanical displacement and electric potential. An active fiber composite model that considers several fibers, epoxy matrix, and electrode fingers (interdigitated electrodes) as part of the representative volume element is developed and implemented using finite element method. The model examines the effect of the interdigitated electrode parameters such as the spacing between the electrode’s fingers and their width. The other parameters examined are the fiber diameter and matrix properties. This parametric study will lead to an optimized geometry and matrix that can be used for the manufacturing of next-generation active fiber composites with higher performance than what is currently available.
Fatigue of Risers: Calibrating Reliability Estimates From Full-Scale Data

A number of measurement campaigns have sought to quantify fatigue damage on drilling and production risers in the field. The data from these campaigns have recently been used to test the accuracy of software predictions of riser motions and hence fatigue. It is often found that state-of-the-art software shows a conservative bias in predicting fatigue damage — conservative factors of 10 or more. At the same time, short-term damage estimates (e.g., over 10-minute intervals) show significant scatter: COV (coefficient of variation) values of 1.0–2.0 are typical.We suggest methods here to better incorporate the information from these measurements into fatigue reliability predictions. We note that (1) software error statistics show markedly different behavior in different regimes; e.g., for different levels of predicted damage; and (2) our fatigue reliability concern lies with the variability not in individual 10-minute damage rates, but rather in the long-run damage rate over the entire structural life. These features suggest a non-parametric approach, in which software error statistics are binned and separately analyzed for different predicted damage levels. The sample means in each bin, together with their variabilities, then form the basis for our reliability assessment.Because our interest lies with the average behavior in each bin, variability reduces notably: COVs of 1.0–2.0 (on individual 10-minute rates) are reduced by an order of magnitude or more. This variability is commonly dominated by the uncertainty in fatigue capacity (S–N curve, Miner’s rule, etc.) Thus, our measurement campaigns are of most interest in predicting only the mean bias in damage predictions; conventional methods are then available to propagate these into a standard fatigue reliability analysis. Results are shown for a number of applications, and implications considered for design (i.e., load factors). Copyright © 2014 by ASME
Field Calibration of Weirs Using Partial Volumetric Flow Measurements

AbstractA simple and low-cost flow-measurement method for the field calibration of weirs is described. With this method, accurate estimations of the flow rate over a weir can be made on the basis of volumetric flow measurements of a fraction of the total flow, using common equipment. Two variants of the method, suitable for the calibration of rectangular or auxiliary profiled weirs, are described. The method, under specific conditions, can be also used for the field calibration of other flow-measurement or irrigation structures.