Miracle-dz/UniFAR-FTUs huggingface dataset:
Online coherency identification and stability condition for large interconnected power systems using an unsupervised data mining technique

Identification of coherent generators and the determination of the stability system condition in large interconnected power system is one of the key steps to carry out different control system strategies to avoid a partial or complete blackout of a power system. However, the oscillatory trends, the larger amount data available and the non-linear dynamic behaviour of the frequency measurements often mislead the appropriate knowledge of the actual coherent groups, making wide-area coherency monitoring a challenging task. This paper presents a novel online unsupervised data mining technique to identify coherent groups, to detect the power system disturbance event and determine status stability condition of the system. The innovative part of the proposed approach resides on combining traditional plain algorithms such as singular value decomposition (SVD) and K -means for clustering together with new concept based on clustering slopes. The proposed combination provides an added value to other applications relying on similar algorithms available in the literature. To validate the effectiveness of the proposed method, two case studies are presented, where data is extracted from the large and comprehensive initial dynamic model of ENTSO-E and the results compared to other alternative methods available in the literature.
Everyday practices of agile software developers

The theory and practice of software engineering is largely represented in the literature by discrete rational models, methodologies, tools and techniques for producing software and for describing work processes as they ought to be done. There has been little research that characterises software development as it is actually practised every day by professional software developers. This thesis addresses that gap. As the recognition of software development as embodied work is fundamental to this research, a situated approach underpins its exploration of software development as it is performed by real developers in their workplace at the time that it occurs. The initial, guiding research question, “So what do software developers do every day? ” was addressed by undertaking a longitudinal ethnographic study, involving two years of fieldwork, of an Australian group of software developers who use an Agile development methodology. A local software development infrastructure, comprising software tools and formal software development policies and procedures, is available to the developers. As the research progressed, it became obvious that they spent an enormous amount of their time and effort dealing with this infrastructure in order to accomplish their daily work. Further, more directed questions about the developers’ daily practice thus became distilled into this one: What significance does their infrastructure have for the developers’ everyday work? The findings challenge two assumptions often implicit in software engineering research interests: firstly, that infrastructure, along with its constituent elements, is a given — a discrete, independent and stable entity — and, secondly, that software development practice can be authentically represented by, and understood in, formal, rational models of software process. The foregrounding of relations between the developers, their infrastructure and their work product forms the crux of this thesis. Its primary contributions are: • It presents an ethnography of a little-studied group: professional software developers; • It provides a detailed account of how the developers’ infrastructure and their work practice are intimately intertwined and mutually constitutive, continuously generating the context in which the design and development of complex software can be accomplished; • It articulates the processes and practices that effect progressive blurring and co-dependency between the software product and the infrastructure; • It identifies and describes essential dimensions of developers’ practice that are missing from accounts and representations such as formal models; • It demonstrates how an explication of local infrastructure is more beneficial to understanding specific software development work practice than abstract definitions of infrastructure which are not constrained by the practicalities of everyday use.
Maintaining TQM in a Nuclear Power Plant through Training

The main of the study used to identify the influence of training program outcome on the total quality management of the nuclear power plant in the UAE. Several sub-variables were identified to ease the process of reaching the research objective. For the purposes of this objective, a quantitative methodology was used. A five-point Likert Scale questionnaire was developed and distributed to the employees of Emirates Nuclear Energy Corporation (ENEC). The sample selection was done purposively with the questionnaire being distributed to five different levels of Management. Data analysis was carried out using the SPSS software. Results indicate that there is a general strong correlation between the training program outcome and the total quality management of the nuclear power plant in the UAE. Results for each of the sub-variable are presented and systematically discussed. Regression analysis was also carried out and a predictive model was developed for the relationship between the dependent and independent sub-variables. It was seen that almost all of the independent sub-variables had and influence on the dependent sub-variable, Knowledge Assets. Furthermore, One-Way ANOVA was carried out and the results of this test showed significant differences between the management groups.
Key issues on Partial Least Squares (PLS) in operations management research: A guide to submissions

Purpose: This work aims to systematise the use of PLS as an analysis tool via a usage guide or recommendation for researchers to help them eliminate errors when using this tool.Design/methodology/approach: A recent literature review about PLS and discussion with experts in the methodology.Findings: This article considers the current situation of PLS after intense academic debate in recent years, and summarises recommendations to properly conduct and report a research work that uses this methodology in its analyses. We particularly focus on how to: choose the construct type; choose the estimation technique (PLS or CB-SEM); evaluate and report the measurement model; evaluate and report the structure model; analyse statistical power.Research limitations: it was impossible to cover some relevant aspects in considerable detail herein: presenting a guided example that respects all the report recommendations presented herein to act as a practical guide for authors; does the specification or evaluation of the measurement model differ when it deals with first-order or second-order constructs? ; how are the outcomes of the constructs interpreted with the indicators being measured with nominal measurement levels? ; is the Confirmatory Composite Analysis approach compatible with recent proposals about the Confirmatory Tetrad Analysis (CTA)? These themes will the object of later publications.Originality/value: We provide a check list of the information elements that must contain any article using PLS. Our intention is for the article to act as a guide for the researchers and possible authors who send works to the JIEM (Journal of Industrial and Engineering Management). This guide could be used by both editors and reviewers of JIEM, or other journals in this area, to evaluate and reduce the risk of bias (Losilla et al., 2018) in works using PLS as an analysis procedure.
Effects of Flipped Learning on University Students’ Academic Achievement in Algorithms and Programming Education

The purpose of this study is to investigate the effect of the "flipped learning" on university students’ academic achievement. In this regard, 220 students studying in Mechanical Engineering and Computer Programming in Aksaray University participated to the study. As data collection tool, an academic achievement test was developed by researchers. Validity and reliability issues for the test were established. Algorithms and Programming were selected as subject areas since university students experience significant learning difficulties. The study, after a pilot study, was carried out for 8 weeks. In data analysis, using SPSS 24 software program, it was analyzed how the dependent variable, academic success, changed according to different teaching methods by using t-test. As a result, it was seen that a significant difference was found between the average scores of students in each program. When the flipped learning for programming education at university level is constructed in a well-structured way, it emerges as an effective learning method for increasing academic success.
Teaching as coaching: Experiences with a video-baed flipped classroom combined with project-based approach in technology and physics higher education

The role of faculty in higher education as knowledge disseminators within the knowledge and digital society can be completely redefined. This paper presents results from a video-based flipped classroom approach combined with a project-oriented learning arrangement. I show that videos combined with a project-based learning setting can be a powerful tool to facilitate the shift from knowledge dissemination to knowledge appropriation. Besides, results show a high level of student's satisfaction and achievement during the course. The competences obtained by the students during the course reach far beyond those possible in a similar course with a traditional teaching approach.
EVALUATION OF SPECTRUM OCCUPANCY AND COMPARISON FOR THREE DIFFERENT REGIONS

Radio spectrum is a scarce source and very significant to measure and monitor. The present spectrum must be exploited efficiently since every new application must be allocated to spectrum. With purpose of using the spectrum efficiently, there are worldwide research efforts on dynamic spectrum access. Among these methods, cognitive radio mostly draws attention. In order to carry out dynamic spectrum access studies successfully, available spectrum must be meticulously analyzed. In this paper, spectrum occupancy measurements between 25-3000 MHz frequency bands were made in three different regions (Selcuklu, Karatay, Meram) of Konya, Turkey in outdoors during six months. Obtained data is presented with graphics. The occupancy ratios are %5.12, %4.46 and %4.19 for Selcuklu, Karatay and Meram, respectively.
Multimodal Haptic Display for Virtual Reality: A Survey

Human haptic perception system is complex, involving both cutaneous and kinesthetic receptors. These receptors work together and enable human to perceive the external world. To simulate immersive interaction with virtual objects in virtual reality scenarios haptic devices are desired to reproduce multiproperties of virtual objects, support multigestures of human hands to perform fine manipulation, produce haptic stimuli for simultaneously stimulating multireceptors (including cutaneous and kinesthetic receptors) of human haptic channel, and thus invoke realistic compound haptic sensations. In recent years, such multimodal haptic devices have emerged. In this paper, we survey the latest progress on multimodal haptic devices, identify the gaps, and put forward future research directions on the topic.
Time-modulated array antennas – theory, techniques, and applications

ABSTRACT This paper aims to present an up-to-date overview of the state-of-the-art about time-modulated arrays (TMAs). Starting from a description of the TMA fundamentals and basic theory in the time and frequency domain, the most popular techniques for synthesizing TMAs are revised. Afterwards, a survey of the main application contexts in which TMAs have been proposed is reported. Finally, current research trends are discussed and future developments envisaged.
Nonlinear analysis of masonry structures using fiber‐section line elements

For seismic analysis of unreinforced masonry (URM) buildings characterized by a box‐like behavior, a widely accepted model is based on the equivalent frame idealization of walls. The equivalent frame model uses 1D elements to represent the vertical piers and horizontal spandrels which are connected by rigid nodes. The mechanical characterization of the elements is one of the crucial aspects to predict reasonably the building seismic behavior. Through the comparison with pseudo‐static and dynamic experimental tests performed on two‐story full‐scale buildings, this paper validates the frame modeling in the OpenSees framework, which includes a fiber‐section force‐based beam element for the axial‐flexural behavior, coupled with a cyclic shear‐deformation phenomenological law.
Accommodating diverse learning styles inthe design and delivery of on-line learning experiences

The primary purpose of this study was to incorporate principles of learning styles theory into thedesign and delivery of Internet-based education. Learning styles theory has long been used byeducators to enhance the learning experience by individualizing it to accommodate the various waysthat students perceive and process information. Although learning style principles have been widelyapplied to more traditional teaching-learning formats, educators have just begun exploring thepotential application to asynchronous formats. This paper first describes Kolb's (1984) theory oflearning styles, and then describes how principles from the theory can be adapted for use withcomputer-delivered instruction. Finally, we report the results of a study designed to measure theeffect of customized instruction on students' perceptions of the learning process, and discuss theimplications for the increasing numbers of faculty and students involved in on-line teaching andlearning.
An Indirect Measurement Method for Gas Consumption of a Diaphragm Gas Meter Based on Gas Pressure Signal Detection

At present, the remote meter reading problem for a large number of existing domestic diaphragm gas meters has not been reliably solved. The diaphragm gas meter uses a physical structure to measure gas consumption, so the main problem of remote meter reading is the digitization of gas consumption. Although it is possible to digitize the consumption data by modifying the internal structure of the gas meter or adding sensors, thereby realizing the function of remote meter reading, the modification process is complicated, the modification cost is high, and manual meter reading can only be used for the existing diaphragm gas meters. For this reason, this paper proposes an indirect measurement method of gas consumption based on gas pressure signal detection. The method can digitalize the metering results of the mechanical diaphragm gas meter and develop a state detection function by analyzing the pressure signal of the outlet of the meter without modifying the internal structure of a meter, thus addressing the key difficulties in the construction of a gas meter remote meter reading system. The experimental results show that this method has small calculation error and high reliability.
First Observations on the Trap-Induced Avalanche Instability and Safe Operating Area Concerns in AlGaN/GaN HEMTs

This paper reports the very first systematic study on the physics of avalanche instability and safe operating area (SOA) reliability in AlGaN/GaN high-electron-mobility transistor (HEMT) using submicroseconds pulse characterization, poststress degradation analysis, well-calibrated TCAD simulations, and failure analysis by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Impacts of electrical and thermal effects on SOA boundary and avalanche instability are investigated. Trap-induced cumulative nature of degradation is studied in detail. The root cause for avalanche instability in AlGaN/GaN HEMTs is investigated. Postfailure SEM, energy dispersive X-ray (EDX), and TEM analysis reveal distinct failure modes in the presence and absence of carrier trapping.
Fuzzy-Based Statistical Feature Extraction for Detecting Broken Rotor Bars in Line-Fed and Inverter-Fed Induction Motors

This paper presents the use of a fuzzy-based statistical feature extraction from the air gap disturbances for diagnosing broken rotor bars in large induction motors fed by line or an inverter. The method is based on the analysis of the magnetic flux density variation in a Hall Effect Sensor, installed between two stator slots of the motor. The proposed method combines a fuzzy inference system and a support vector machine technique for time-domain assessment of the magnetic flux density, in order to detect a single fault or multiple broken bars in the rotor. In this approach, it is possible to detect not only the existence of failures, but also its severity. Moreover, it is not necessary to estimate the slip of the motor, usually required by other methods and the damaged rotor detection was also evaluated for oscillating load conditions. Thus, the present approach can overcome some drawbacks of the traditional MCSA method, particularly in operational cases where false positive and false negative indications are more frequently. The efficiency of this approach has been proven using some computational simulation results and experimental tests to detect fully broken rotor bars in a 7.5 kW squirrel cage induction machine fed by line and an inverter.
Improved Heart-Rate Measurement from Mobile Face Videos

Newtonian reaction to blood influx into the head at each heartbeat causes subtle head motion at the same frequency as the heartbeats. Thus, this head motion can be used to estimate the heart rate. Several studies have shown that heart rates can be measured accurately by tracking head motion using a desktop computer with a static camera. However, implementation of vision-based head motion tracking on smartphones demonstrated limited accuracy due to the hand-shaking problem caused by the non-static camera. The hand-shaking problem could not be handled effectively with only the frontal camera images. It also required a more accurate method to measure the periodicity of noisy signals. Therefore, this study proposes an improved head-motion-based heart-rate monitoring system using smartphones. To address the hand-shaking problem, the proposed system leverages the front and rear cameras available in most smartphones and dedicates each camera to tracking facial features that correspond to head motion and background features that correspond to hand-shaking. Then, the locations of facial features are adjusted using the average point of the background features. In addition, a correlation-based signal periodicity computation method is proposed to accurately separate the true heart-rate-related component from the head motion signal. The proposed system demonstrates improved accuracy (i.e., lower mean errors in heart-rate measurement) compared to conventional head-motion-based systems, and the accuracy is sufficient for daily heart-rate monitoring.
Gait analysis: Is it easy to learn to walk like someone else?

In this master’s thesis, we will look at whether it is easy or difficult to learn to walk like someone else in such a way that one will be accepted by an authentication system, based on gait. In the last couple of years, there have been some studies about whether gait can be used in order to authenticate a person. If it turns out to be very easy to learn to walk like another person, then gait authentication should probably not be used as the only authentication technique. We investigate the ease of gait mimicking by means of a 3-axis sensor worn by the user. A prototype is created, which reads this acceleration data, and plots it as 3 graphs in a coordinate system, shown on a big screen. The aim is to see whether the user manages to learn to walk in such a way that his graphs match 3 template graphs, which are also plotted in the same coordinate system. Every attempt lasts 5 seconds, and a score between 0 and 100 will be given in the end of each, based on how similar the impersonator’s graphs are to the original graphs. We use Pearson’s correlation to calculate this. The experiment has 13 participants, and we have created 5 different templates which each participant will attempt to imitate 15 times. The results from our data analysis are showing that it actually seems rather easy to learn to walk like another person, and hence to be accepted by a gait authentication system.
Modified Traffic Flow Model with Connected Vehicle Microscopic Data for Proactive Variable Speed Limit Control

Most previous prediction based Variable Speed Limit (VSL) control strategies focused on improving traffic mobility based on the macroscopic traffic data. Nowadays, the emerging technologies provide access to the microscopic traffic flow data, which better captures the details of traffic flow dynamics in the VSL controlled environment. Thus, in this paper, the microscopic traffic flow data were utilized as a supplement to predict the evolutions of traffic flow parameters. The proposed VSL control algorithm adopts the Model Predictive Control (MPC) framework, which employs a modified version of the classic traffic flow model METANET to take advantage of the microscopic data in traffic flow predictions. The microscopic traffic simulation software VISSIM was used to establish an experimental simulation platform and perform real time traffic responsive control based on field data. The proposed control strategy was evaluated against the no-VSL control and macroscopic-based VSL controlled scenario. The results show that utilizing the proposed modified METANET model reduced the error in speed prediction accuracy and improved system mobility performance.
Experimental Study of the Summation of Flicker Caused by Wind Turbines

Integration of wind energy into the grid faces a great challenge regarding power quality. The International Electrotechnical Commission (IEC) 61400-21 standard defines the electrical characteristics that need to be assessed in a Wind Turbine (WT), as well as the procedure to measure the disturbances produced by the WT. One of the parameters to be assessed are voltage fluctuations or flicker. To estimate the flicker emission of a Wind Power Plant (WPP), the standard establishes that a quadratic exponent should be used in the summation of the flicker emission of each WT. This exponent was selected based on studies carried out in WPPs with type I and II WTs. Advances in wind turbine technology have reduced their flicker emission, mainly thanks to the implementation of power electronics for the partial or total management of the power injected into the grid. This work is based on measurements from a WPP with 16 type III WTs. The flicker emission of a single WT and of the WPP were calculated. Low flicker emission values at the Point of Common Coupling (PCC) of the WPP were obtained. The flicker estimation at the PCC, based on the measurement from a single WT, was analyzed using different exponents. The results show that a cubic summation performs better than the quadratic one in the estimation of the flicker emission of a WPP with type III WTs.