Miracle-dz/UniFAR-FTUs huggingface dataset:
An Adaptive Resistance Perturbation Based MPPT Algorithm for Photovoltaic Applications

This paper proposes a Resistance perturbation based maximum power point tracking (MPPT) with an adaptive control limit algorithm to extract the maximum power from solar photovoltaic (PV) array. This algorithm consists of two main functions, namely 1) resistance perturbation & observation (RP&O) and 2) adaptive resistance control (ARC) limit. The RP&O operates the PV array at maximum power point (MPP), and the ARC limit continuously monitors the resistance of the PV $R_{pv} $ to determine the operating limit of MPP. The ultimate aim of proposing this algorithm is to reduce the oscillations and improve MPP’s tracking performance for sudden variation in temperature and irradiance conditions. Furthermore, it does not require an expensive pyranometer or temperature sensor to track the MPP of the PV array. This paper also compares the proposed and conventional MPPT algorithm’s performance. Its validation results in both MATLAB/Simulink and experimental studies are presented under constant and sudden changes in irradiance conditions.
Optimal PV Inverter Control for Network Voltage and Power Factor Regulation

Increasing the installation of photovoltaic systems (PV) in the distribution network poses challenges for maintaining grid stability. In the case that the PV power is higher than the load, reverse active power flow causes the network voltage to rise. The reverse flow also affects the power factor ($pf$) in any bus connected to a load. To keep the voltage and $pf$ within limits and maximize the active power of PV systems, a decentralized power dispatch control (DPDC) design is shown. This control strategy utilizes the reactive power of the PV system to keep the voltage and $pf$ at an allowable level while not exceeding the PV capacity and reactive power limits. The method is validated by a MATLAB simulation and is compared to a simple on/off overvoltage control (OVC).
Static Extraction of Enforced Authorization Policies SeeAuthz

Authorization is an intrinsic part of a software’s security. Determining whether a user is allowed to access a resource or not is crucial, not only in safety-critical applications but also in everyday applications to prevent misuse of data or software. There is plenty of research dealing with validating and verifying authorization policies in the security community. Still, an implemented authorization policy does not necessarily match the planned authorization policy, i.e., even a validated and verified authorization policy can pose security issues when implemented incorrectly. This gap between planned and implemented authorization policy poses the risk of unauthorized access to sensitive resources due to insufficient authorization checks. Therefore, it is essential to ensure a system’s security to validate the implemented authorization policy against the planned one. We, therefore, describe the authorization pattern and present an algorithm to extract authorization graphs from implemented authorization policies, which can then be used to compare against the planned authorization policy. To that end, we developed a configurable context-sensitive analysis tailored to Java-based software systems, where the context is the authorization facts that hold on each point. Using a configuration for Apache Shiro, a security library that supports authorization, we evaluated our implementation using an open-source repository system for the management and dissemination of digital content and a closed-source manufacturing execution system. We discuss additional usage scenarios of the analysis results and describe how to transfer the approach to other authorization policies and programming languages.
Game-Like Captchas for Intrusion Detection

In this paper, we consider a novel method of mining biometric data for user authentication by replacing traditional captchas with game-like captchas. The game-like captchas present the user with a short game in which they attempt to get a high score. The data produced from a user’s game play will be used to produce a behavior biometric based on user interactions, such as mouse movement, click patterns and game choices. The baseline expectation of interactive behavior will be used as a single factor in an intrusion detection system providing continuous authentication, considering the factors such as IP address, location, time of use, website interactions, and behavior anomalies. In addition to acting as a source of data, game-like captchas are expected to deter bots and automated systems from accessing web-based services and improving the user experience for the end-users who have become accustomed to monotonous alternatives, such as Google’s re-captcha.
Arduino based Open Source Electronic Control Unit for Electric Utility Vehicles

This paper presents the design and development of a low-cost Electronic Control Unit (ECU), aimed for the application and control of Electric Utility Vehicles (EUV). The selection of components and features, as well the design and project of all the necessary hardware, was also carried out. The major features that overcome other available solutions are: multiple Controller Area Network (CAN) buses, electrical isolation of inputs, outputs, two CAN buses and serial interface, outputs with current feedback and its reduced overall cost. Validation tests were conducted in order to verify all functionalities. Moreover, an electric vehicle simulator was developed to assess the performance of the ECU in a real world working environment. The fully functional prototype of the ECU proved to be robust and experimental results fulfill the proposed objectives.
Implementation of a Power Hardware In-The-Loop Platform Using the Damping Impedance Method

This paper presents the practical implementation of a PHIL simulation platform using the damping impedance method. To be successful this requires the identification of the impedance of the hardware under test. We use an identification strategy based on spectral analysis, to obtain a non-parametric identification of the HUT's impedance, followed by a fitting routine that obtains a parametric representation of it. The PHIL platform is then simulated to test the identification routine with passive and active HUTs. Implementation of the PHIL platform is done in a multi-core real-time target, allowing for the electrical simulation and identification routine to run in parallel, on the same device. Experimental verification of the simulated scenarios is performed. A fundamental difference between the identification of passive and active HUTs is found and strategies on how to cope with it are proposed and implemented. Finally, recommendations are given about the realisation of further PHIL simulations with the platform.
MOVING BEYOND NOVELTY: CREATING EFFECTIVE 3-d FLY-OVER MAPS

This paper seeks answers to basic questions about the design and use of 3-d fly-over maps: (1) what are they good for (i.e., for what kinds of map-reading tasks), (2) what are their limitations and when should their use be avoided, and (3) what are proven or potential design innovations for making more effective 3-d fly-over maps. In this paper we identify four major problems with fly-over maps, and present solutions to each of these problems: (1) limitations of an oblique perspective, (2) information overload, (3) visual occlusion, (4) and user disorientation. Because research on 3-d views and immersive technology is spread across a number of disciplines (e.g., human computer interaction, geovisualization, psychology) we present a synthesis of findings that can inform good cartographic practice. This paper, however, is equally a call for further research as many questions that are outlined here remain unanswered.
Loss and Post-founder Business Discontinuity among selected Indigenous Private Enterprises in South-West Nigeria

The survival of indigenous private enterprises is usually threatened by the demise of their founders. While previous studies on enterprise (dis)continuity have focused largely on business failure before founders’ death, little attention is paid to why indigenous private businesses do not outlive their founders in Nigeria. This study, therefore, examined the factors accounting for post-founder business discontinuity among selected indigenous private enterprises in the South-West, Nigeria. Theory of Loss and continuity in the family firm provided the framework. The research design was exploratory, using qualitative methods of data collection. Three states (Lagos, Ogun and Oyo) were purposively selected on the basis of being home to many defunct indigenous enterprises. Case studies were done on 16 purposively selected indigenous private enterprises (eight discontinued and eight surviving) whose founders had died. The qualitative data were analysed with Nvivo 8. Findings show that disharmony in the deceased founders’ family, ineffective implementation of succession plans as well as inheritance crises emerged as the most prevalent factors that accounted for postfounder enterprise discontinuity. The study recommended that indigenous enterprise founders should make efforts to foster harmonious relationships among members of their families in order to increase enterprise survival after their death.
Factors that may interfere in the success of fixed time artificial insemination (TFAI) in pig production

In an intensive system such as modern pig farming, one of the main objectives of reproductive biotechniques is to allow genetic improvement. Besides this, it also allows to reduce the necessary labor requirements in the production system, optimizing the handling in a natural way. Thus, other goals can be achieved, like reducing costs with breeding or inseminating doses and also with materials needed in some processes during production. Finally, the objective is also to increase the productivity, but its maintenance becomes satisfactory since the other objectives, mainly in relation to the diffusion of genetic material and the reduction of costs, the use of these biotechniques becomes feasible according to your progress. Thus, the objective of this review was to address the main causes that may lead to failure to implement TFAI in reproductive programs, from an approach that considers terms related to the industrial sectors, in order to bring producers closer to reality of a increasingly professional and competitive production and creation system.
Spontaneously emerging cortical representations of visual objects and features in human visual cortex

The function of spontaneous brain activity is unknown. Here we test the novel hypothesis that patterns of spontaneous activity reflect not only synaptic homeostasis or synchronization of neuronal populations, but code representational patterns evoked by stimuli and tasks. We compared in visual cortex the spatial patterns of spontaneous activity to the patterns evoked by ecological visual stimuli (faces, bodies, scenes) and low-level visual features (e.g. phase-scrambled faces). We identified regions that preferred particular stimulus categories during localizer scans, measured multivariate spatial patterns for each category during task scans, and then spatially correlated these stimulus-evoked patterns to the pattern measured in each frame of resting-state scans. The mean correlation coefficient was essentially zero for all regions/stimulus categories, indicating that resting activity patterns were not biased toward particular stimulus categories. However, the spread of correlation coefficients, i.e. both positive and negative, was significantly greater for a stimulus category over the ROIs preferring that category (e.g. the body category in body-preferring ROIs). Therefore, the putative representational content of spontaneous activity was related to stimulus-evoked spatial activity patterns. This content also governed the temporal correlation or functional connectivity of spatial patterns of spontaneous activity between individual regions. Resting spatial activity patterns related to an object category (e.g. bodies) fluctuated preferentially between ROIs preferring the same category. Moreover, activity patterns related to different categories fluctuated independently within their respective preferred ROIs. These results support the general proposal that spontaneous multi-voxel activity patterns are linked to stimulus-evoked patterns, consistent with a representational function for spontaneous activity. All rights reserved. No reuse allowed without permission. The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. https://doi.org/10.1101/518712 doi: bioRxiv preprint
Finding eigenvalues and corresponding eigenvectors through applying (F.E.M) to elliptic (P.D.E) Using different methods

In this paper the power method and the symmetric power method are applied to the matrix which was otained from a linear system this system was derived from an elliptic partial differential equation by adopting the finite element method in order to find eigenvalues and the corresponding eigenvectors. These methods are applied to two examples. The different of the two examples are compared to find out the differences between them. The paper has shown that the use of symmetric power method leads to a large eigenvalue if compared to the use of the power method.
Human Spatial Attitude Control by Means of Zero Momentum Turns

This work proposes a methodology for the automatic control of the angular orientation of a multibody system based upon the preservation of its angular momentum. The control strategy used is hierarchical and decentralized arranging the control stages in levels of attributions and complexity. At a lower level the controllers are responsible for handling each of the multibody degrees-of-freedom forcing them to follow prescribed reference motions through the use of error feedback. Middle level controllers coordinate the lower level controllers so that each of the multibody sub-systems achieve prescribed reorientation. These reorientations are defined by a higher level controller with the final objective of reorienting the complete multibody system to reach a different attitude. The underlying control strategy of the multibody is applied to the human spatial attitude in a zero gravity environment. Here, the biomechanical model used is defined such a way that all biomechanical joints are described by joints with one or two degrees-of-freedom, to which lower level controllers are associated. A formulation based on natural coordinates is used to describe the multibody system due to its ease of representing the biomechanical features of the model. The physiological data for the biomechanical model is described in a database where information for different subjects is available. In this form the application case is not dependent in a particular human subject but can be used in general cases. The control laws associated with the controllers are parametrically adjusted for the biomechanical model under analysis. The results obtained are finally discussed in face of the modeling assumptions made and control laws used.
How Many Likes Are Good Enough? An Evaluation of Social Media Performance

Abstract This paper considers the evaluation of social media performance from a user’s perspective using the expectation confirmation theory as the theoretical framework. The interplay between initial expectations and subsequent evaluations of social media performance, in particular, forms the basis of the evaluation. The research focuses on the influence that the performance of brand-related user-generated content is able to exert on a user’s brand attitude, self-image, and the development of their personal brand. This conceptual paper develops three propositions suggesting that the social media performance of brand-related user-generated content is able to influence one’s brand attitude, self-image, and personal brand respectively. A typology of four different social media user types is developed through an evaluation of the disconfirmation experienced as a result of the interplay between initial expectations and the actual evaluation of the performance of brand-related, user-generated content. The concept of social media performance is proposed, which considers the subjective evaluation of the performance of a brand-related post shared on social media platforms. In addition, the research expands the expectation confirmation theory to a new context in order to offer a more nuanced understanding of an existing yet under researched phenomenon.
MOTHER’S KNOWLEDGE DAN ATTITUDE ABOUT STUNTING OF CHILDREN IN NAMORAMBE DISTRIC

Stunting was associated by chronic malnutrition due to intake of nutrients that are lacking in a long time in children. This condition causes the child to have a height tends to be short in his age. The incidence of stunting is influenced by care in the family, especially related to the knowledge and attitudes of mothers in the event of stunting. Treatment from pregnancy to child is related to the fulfillment of food and family nutrition. This research is descriptive which aims to describe the knowledge and attitudes of mothers in the incidence of stunting in children. Population of all mothers with babies and toddlers in Namo Rambe sub-district. Samples are families / parents who have children aged one to 5 years. Data collection uses a questionnaire, which consists of demographic data, data on mother's knowledge and attitudes. Univariate data analysis uses the frequency of distribution and presentation. The results of mother's knowledge about stunting in general are in the low category at around 50.7%. The mother's attitude is in the negative attitude which is around 55.8%. Health workers must be able to optimize their role in providing health education to the community specifically about stunting.
Gambia publications in the Science Citation Index Expanded: bibliometrics of institutions and subjects

: Gambia is the smallest country in West Africa and it has contributed to the academic world over the past decades. This study characterized document type, language, publication trend, subject category, international collaboration of Gambia publications during 1900-2016 based on Science Citation Index Expanded in Web of Science. Results showed that Gambia is highly reliant on foreign and international collaboration in research, especially with the UK and USA. International collaboration was responsible for the increasing scientific production and scientific impact of Gambia over the years. Medical Research Council (MRC) contributed the most Gambia publications, and played an important role in conducting international collaboration. Most of Gambia publications focused on tropical medicine, environmental and occupational public health, immunology and infectious diseases. Gambia has attracted increasing attention from the academic world, with improving scientific production and scientific impact, signalling more prestige in the scientific community. With the information and insights provided in this paper, we managed to obtain a quick overview of Gambia publications that can help make strategic decisions for researchers and governors of scientific research.
The chemistry of wood strength

On etudie les relations entre les proprietes mecaniques de la fibre de bois et ses constituants chimiques (cellulose, hemicellulose, lignine) aux niveaux macroscopique (cellulaire), microscopique (paroi cellulaire) et moleculaire (polymeres)
Energy storage, body size and immune response of herbivore beetles at two different elevations in Costa Rica

The physiological condition and immune responses of organisms living at different elevations are expected to display local adaptations to the different climatic and biotic conditions. Small ectotherms with specialized diets are highly susceptible to environmental change, as their life cycle is largely affected by temperature and by the presence of specific resources. This study focuses on two species of rolled-leaf beetles (Chrysomelidae), both present at two different elevations in Costa Rica: Cephaloleia belti Baly, a diet-generalist, and Chelobasis bicolor Gray, a diet-specialist. Body size, energetic condition (lipid storage), muscle mass and immune condition (melanization response) were compared in beetle populations from a tropical rainforest (50 m elevation) and a tropical montane forest (2 000 m elevation). These measurements reflect current and past nutritional condition and hence are good estimators of individual fitness. We analyzed a total of 172 individuals from both species, sexes and elevations. We predicted that beetles at higher elevation would display larger body size, higher energetic condition and lower immune response associated with metabolic requirements and parasitic pressure in colder temperatures. In general, beetles at high altitude were larger, had more lipids and muscle and showed stronger melanization (i.e., immune response) than beetles at low altitudes. Such differences among populations at different elevations may reflect local adaptation to altitude or phenotypic plasticity. However, the effect of elevation was not equivalent amongst species or sex. Measuring physiological traits in organisms with broad elevational distributions could be useful in understanding possible species responses to climate change.
TOWARD AN OCCLUDED AUGMENTED REALITY FRAMEWORK IN E-LEARNING PLATFORMS FOR PRACTICAL ACTIVITIES

With the evolution of the internet and related technologies, a wide range of innovative solutions are introduced in order to solve different problems in several fields. One of the most prominent innovations is the E-learning platforms. These platforms allow the instructor to manage and control the learning content that the end user is going to consume. In many domains, the learner needs to have access to laboratory materiel and to manipulate some equipment in order to complete the theoretical background built in the course. Moreover, the use of videos, virtual laboratories or distance control of real equipment, to solve the existence of the practical activities in the E-learning platforms, is limited in occurrence and results. The Augmented Reality and the Augmented-Virtuality are the new technologies that promise to create a virtual environment, which gives the learner a virtual experiment space where s/he can experiment safely and with total control. In this paper, the authors propose a solution to carry out the practical activities in some E-leaning platforms whereby the learner can manipulate the virtual experiment elements like in real world: freely and safely without any risks. A survey was given to a sample of students, an instructor and a designer after a practical activity simulation, in order to get their feedbacks and to evaluate the proposed solution.
Study the migration behavior of fish by optical flow

Motion analysis of living animals might help to understand the dangers that threaten the species, but it is sometimes technically challenging. Here, we investigate the use of computer vision for automatic tracking and acquisition of knowledge about the migratory behavior of elver. For that purpose, some elvers are color-marked and then introduced into an experimental medium reproducing tidal conditions. Observations are collected in video sequences. To get information about fish behavior, one can track their motion by optical flow methods. This article addresses the task of estimating the motion of elver by the algorithm of Horn &Schunck. Preliminary results show that one can estimate the speed but also the swimming behavior, hence eventually leading to energetic information about the animals.