Miracle-dz/UniFAR-FTUs huggingface dataset:
The role of the South African qualifications authority in curbing misrepresentation of qualifications

This study sought to analyse the role of the South African Qualifications Authority in curbing the misrepresentation of qualifications. Academic degrees are highly valued throughout the globe because they are seen as a dependable and trusted proxy for the bearers' knowledge, abilities and skills. In the same vein, the higher education system in South Africa makes every effort to generate well-qualified graduates who are capable of assisting in the leadership of the country's socio-economic growth. Recent reports in the media, on the other hand, create the impression that this initiative is being hampered by the widespread use of counterfeit, phoney and other illegitimate credentials. Consequently, the reputation of the South African Qualifications Authority (SAQA) is in grave danger as a result of the increasing prevalence of dishonestly misrepresented qualifications in both the public and private sectors. The education system is also at risk of losing its credibility as a result of actions involving deception, which is a subject that has to be addressed at the highest levels possible. Notably, the public service in South Africa is making significant progress towards the goal of ensuring that individuals who misrepresent their qualifications are barred from ever working in the public sector again. In this regard, SAQA plays an important role by offering verification services to individuals who are interested in applying for jobs in the public sector. Thus, this study contributes to the literature on credentialism and qualifications from the developing world with specific reference to South Africa.
Scale Dependence of Power Spectrum: Resulting from Non-Bunch-Davies Modes in de Sitter Background

In this paper, we calculate corrections of scalar perturbations spectra resulting from non-Bunch-Davies modes as the general initial states. First, by considering the asymptotic expansion of the Hankel functions up to the higher order of 1/kη, we modify Mukhanov equation and obtain general solutions of it. We nominate this non-trivial excited solution as the fundamental vacuum mode functions during inflation. Then, we calculate power spectrum with this alternative vacuum mode and we obtain modified form of scaledependent power spectrum with trans-Planckian corrections. Also, unlike the conventional methods, we consider de Sitter space-time instead Minkowski space-time as a background. The method used for renormalization preserves the space-time symmetry, and gives the finite power spectrum and this motivates us to use of excited de Sitter modes. Finally, by considering recent Planck and WMAP results, we give an observational motivation for our non-Bunch-Davies vacuum modes. ar X iv :1 40 2. 69 68 v1 [ as tr oph . C O ] 2 7 Fe b 20 14
Determinants Influencing the Continuous Intention to Use Digital Technologies in Higher Education

There is increasing evidence that the lack of access to digital information and technologies is not widely considered in the educational sectors when focusing on the perceived experience, tutor quality and students’ satisfaction. In this paper, we report on an evaluation of a project aiming to bridge the use of digital information in the educational sector by proposing an integrated model that measures teachers’ quality, uncertainty avoidance effects and students’ satisfaction concerning TAM constructs and the perceived experience of digital information in education (DIE). The model and hypotheses were validated using data collected from a survey of 553 students at a college level. The results revealed that users may perceive the importance of DIE based on several external factors that enhance their learning and teaching experiences. The personal characteristics of the user including his/her readiness to use technology are crucial in correlation with the perceived ease of use. In addition, the high quality of the tutor in some cultures may enhance the perceived usefulness of the technology. Other factors such as flow of information, uncertain avoidance and satisfaction may strongly assess the continuous intention to use the technology.
Synthèse de réseaux à composantes connexes unicycliques

Cette these s'inscrit dans le domaine de l'optimisation combinatoire. Elle utilise l'approche polyedrale pour resoudre des problemes combinatoires qui se posent dans le contexte des reseaux de telecommunications. Nous introduisons et etudions le probleme de synthese de reseaux a composantes connexes unicycliques. Apres avoir rappele que le probleme est facile a resoudre en absence d'autres contraintes, nous etudions de nouvelles variantes en integrant de nouvelles contraintes techniques. Nous commencons par une contrainte portant sur la taille des cycles. Nous souhaitons interdire tous les cycles contenant au plus $p$ sommets. Le probleme est alors NP-Difficile. Des inegalites valides sont alors proposees pour ce probleme. On montre sous des conditions bien precises que ces inegalites peuvent etre des facettes. Plusieurs algorithmes polynomiaux ont ete proposes pour la separation des inegalites valides. Ces algorithme sont mis en oeuvre et des resultats numeriques sont donnes. Nous nous focalisons par la suite sur un nouveau probleme dit de Steiner consistant a partitionner un reseau en composantes unicycliques tout en imposant que certains sommets soient sur les cycles. On montre alors que ce probleme est facile au sens de la complexite algorithmique en proposant un algorithme polynomial et une formulation etendue du probleme. On presente egalement une description partielle de l'enveloppe convexe des vecteurs d'incidence de ces reseaux. La separation des inegalites est egalement etudiee. Nous proposons notamment une generalisation de l'algorithme de Padberg-Rao pour separer les inegalites Blossom. D'autres contraintes techniques sont prises en compte : contraintes de degres, contrainte sur le nombre de composantes connexes, appartenance de certains sommets a une meme composante connexe et enfin la separation de certains sommets qui doivent etre sur des composantes differentes. Enfin, nous faisons une etude spectrale de deux classes specifiques de graphes unicycliques.
IMPACT OF DIFFERENT AMARANTHACEAE EXTRACTS ON THE BIOFILM-FORMING CAPACITY OF SEVERAL BACTERIAL PATHOGENS

Amaranthaceae Juss. family encompasses many edible plants with prominent biological activity. This investigation tested the bioactive properties of ethanolic and methanolic extract of three well-known species: spinach (Spinacia oleracea L.), chard (Beta vulgaris L. subsp. vulgaris), and orache (Atriplex hortensis L.) through the determination of total phenolic and flavonoid content, antioxidant activity, and antibacterial properties. The particular goal was to evaluate the antibiofilm potential of extracts and to demarcate concentration-depending changes in the biofilm-forming category of included bacterial strains. The mass of the chard and orache methanolic extracts gained by maceration are lower in comparison to the mass of ethanolic extracts obtained by the Soxhlet method. In the case of spinach, the results are the opposite. All extracts have an antiradical activity that can be attributed to the established amounts of phenols and flavonoids. Total phenolics in dry leaves ranged from 0.09 to 0.44 mg GAE/g dw, and total flavonoids from 0.42 to 1.9 mg RTE/g dw. All investigated extracts performed inhibitory potential in terms of bacterial growth, while there was no bactericidal effect observed. Values of the minimum inhibitory concentration ranged from 125 µg/ml to 500 µg/ml. Overall results suggested orache extracts as the strongest inhibitory agents. Antibiofilm assays showed that examined extracts of spinach, chard, and orache caused changes in the biofilm-forming capacity of investigated bacterial pathogens. Fluctuations in observed biofilm-forming categories after application of extracts were concentration-dependent.
Design and Implementation of a New Local Alignment Algorithm for Multilayer Networks

Network alignment (NA) is a popular research field that aims to develop algorithms for comparing networks. Applications of network alignment span many fields, from biology to social network analysis. NA comes in two forms: global network alignment (GNA), which aims to find a global similarity, and LNA, which aims to find local regions of similarity. Recently, there has been an increasing interest in introducing complex network models such as multilayer networks. Multilayer networks are common in many application scenarios, such as modelling of relations among people in a social network or representing the interplay of different molecules in a cell or different cells in the brain. Consequently, the need to introduce algorithms for the comparison of such multilayer networks, i.e., local network alignment, arises. Existing algorithms for LNA do not perform well on multilayer networks since they cannot consider inter-layer edges. Thus, we propose local alignment of multilayer networks (MultiLoAl), a novel algorithm for the local alignment of multilayer networks. We define the local alignment of multilayer networks and propose a heuristic for solving it. We present an extensive assessment indicating the strength of the algorithm. Furthermore, we implemented a synthetic multilayer network generator to build the data for the algorithm’s evaluation.
Galaxy pairs in the Sloan Digital Sky Survey – XII. The fuelling mechanism of low-excitation radio-loud AGN

We investigate whether the fuelling of low excitation radio galaxies (LERGs) is linked to major galaxy interactions. Our study utilizes a sample of 10,800 spectroscopic galaxy pairs and 97 post-mergers selected from the Sloan Digital Sky Survey with matches to multi-wavelength datasets. The LERG fraction amongst interacting galaxies is a factor of 3.5 higher than that of a control sample matched in local galaxy density, redshift and stellar mass. However, the LERG excess in pairs does not depend on projected separation and remains elevated out to at least 500 h 1 70 kpc, suggesting that major mergers are not their main fuelling channel. In order to identify the primary fuelling mechanism of LERGs, we compile samples of control galaxies that are matched in various host galaxy and environmental properties. The LERG excess is reduced, but not completely removed, when halo mass or D4000 are included in the matching parameters. However, when both Mhalo and D4000 are matched, there is no LERG excess and the 1.4 GHz luminosities (which trace jet mechanical power) are consistent between the pairs and control. In contrast, the excess of optical and mid-IR selected AGN in galaxy pairs is unchanged when the additional matching parameters are implemented. Our results suggest that whilst major interactions may trigger optically and mid-IR selected AGN, the gas which fuels the LERGs has two secular origins: one associated with the large scale environment, such as accretion from the surrounding medium or minor mergers, plus an internal stellar mechanism, such as winds from evolved stars.
Identification of critical success factors for implementing sustainable public lighting management in cities: literature-based applications

Goal: The objective of this study was to conduct an exploratory literature search capable of identifying the critical success factors for the implementation of sustainable public lighting management in cities. Design / Methodology / Approach: To accomplish this, the chosen method was a systematic literature survey conducted according to the Cochrane protocol, using the Web of Science, Scopus, and Science Direct journal databases. Results: As a result, the study shows that there is a scarcity of scientific literature published in journals regarding the intersection between sustainable management and public lighting. In addition, it became clear that the main practices carried out in this area occur in European cities. Limitations of the investigation: VOSviewer software was used to build and visualize the bibliometric networks and only two correlated attributes were identified, which shows a lack of similarity between them and demonstrates a limitation of this study. Practical applications: As a practical implication, the present study supports public managers in decision-making regarding sustainable public lighting, demonstrating the need to implement projects in this field. Originality/Value: Although this is an extremely important subject, the search showed few studies published in this field.
Cascade Control for Robust Tracking of Continuum Soft Robots With Finite-Time Convergence of Pneumatic System

Pneumatic soft robots have become the premier soft robot type among the plethora of soft robot testbeds under research, being the continuum pneumatic soft robot (cPSR) the most compliant, yet challenging due to its hyperelastic behavior of its constitutive elastomer material. In this type of cPSR, embedded pneumatic chambers materialize the pneumatic controller from within, thus, there arises two highly intertwined dynamical systems: the kinetic one due to the cPSR inertia and to the pneumatic system itself. Unfortunately, the embedded pneumatic control for the cPSR has been outlined using pneumatics developed for rigid bodies. In this letter, we study the resultant Lagrangian dynamics of the highly coupled nonlinear cPSR system equipped with 3 embedded pneumatic chambers (thus the system is fully actuated and controllable). Then, a robust feedback cascade tracking controller is proposed so that the cPSR control torque yields the desired pressure for the pneumatic dynamics. Chatterless integral sliding modes are proposed to render semi-global finite-time convergence of pressure tracking errors. Finally, simulations are presented, and concluding remarks are discussed.
Model reference adaptive integral sliding mode control for switched delay systems

This paper proposes a strategy of model reference adaptive integral sliding mode variable structure control to solve the tracking problem for a class of uncertain switched systems with time-varying delay. A stable integral sliding surface is first constructed. An adaptive control technique is used to adapt the unknown upper bounds of perturbations. Furthermore, adaptive variable structure controllers are employed such that the switched delay system containing perturbations with unknown upper bounds tracks the reference model under arbitrary switching signals. Finally, a numerical example is given to illustrate the effectiveness of the proposed design method.
Implementation of a dark zone maintenance algorithm for speckle drift correction in a high contrast space coronagraph

Abstract. Due to the limited number of photons, directly imaging planets requires long integration times with a coronagraphic instrument. The wavefront must be stable on the same time scale, which is often difficult in space due to time-varying wavefront errors from thermal gradients and other mechanical instabilities. We discuss a laboratory demonstration of a photon-efficient dark zone maintenance (DZM) algorithm in the presence of representative wavefront error drifts. The DZM algorithm allows for simultaneous estimation and control while obtaining science images and removes the necessity of slewing to a reference star to regenerate the dark zone mid-observation of a target. The experiments are performed on the high-contrast imager for complex aperture telescopes at the Space Telescope Science Institute. The testbed contains an IrisAO segmented primary surrogate, a pair of continuous Boston Micromachine (BMC) kilo deformable mirrors (DMs), and a Lyot coronagraph. Both types of DMs are used to inject synthetic high-order wavefront aberration drifts into the system, possibly similar to those that would occur on telescope optics in a space observatory, which are then corrected by the BMC DMs via the DZM algorithm. In the presence of BMC, IrisAO, and all DM wavefront error drift, we demonstrate maintenance of the dark zone contrast (5.8 − 9.8 λ / Dlyot) at monochromatic levels of 8.5 × 10 − 8, 2.5 × 10 − 8, and 5.9 × 10 − 8, respectively. In addition, we show multiwavelength maintenance at a contrast of 7.0 × 10 − 7 over a 3% band centered at 650 nm (BMC drift). We demonstrate the potential of adaptive wavefront maintenance methods for future exoplanet imaging missions, and our demonstration significantly advances their readiness.
Radar Target Detection Algorithm Using Convolutional Neural Network to Process Graphically Expressed Range Time Series Signals

Under the condition of low signal-to-noise ratio, the target detection performance of radar decreases, which seriously affects the tracking and recognition for the long-range small targets. To solve it, this paper proposes a target detection algorithm using convolutional neural network to process graphically expressed range time series signals. First, the two-dimensional echo signal was processed graphically. Second, the graphical echo signal was detected by the improved convolutional neural network. The simulation results under the condition of low signal-to-noise ratio show that, compared with the multi-pulse accumulation detection method, the detection method based on convolutional neural network proposed in this paper has a higher target detection probability, which reflects the effectiveness of the method proposed in this paper.
Hypoxia Confers Tumor with a Higher Immune Infiltration but Lower Mutation Burden in Gastrointestinal Cancer

Background Hypoxia is one of the driving forces of cancer progression, recurrence, and metastasis. However, the association between the tumor hypoxic tumor microenvironment and the tumor mutation burden (TMB) is poorly understood in gastrointestinal cancer. Methods Approximately 2,000 samples from colorectal cancer (CRC) and stomach adenocarcinoma (STAD) patients were obtained from the gene expression omnibus database and the cancer genome Atlas databases and were clustered and subtyped by nonnegative matrix factorization. Significant differentially expressed genes that were possibly related to survival differences between the hypoxic and normoxic groups were subjected to multivariate Cox regression. Results Gastrointestinal cancer patients with CRC and STAD were further divided into two subgroups, namely, the hypoxia group and the normoxia group, and hypoxia was correlated with unfavorable outcomes. Notably, hypoxic tumors had lower TMB but significantly higher levels of immune and stromal infiltration. A signature of HEYL and NRP1 selected by LASSO classified gastrointestinal cancer patients into either a low or high-risk group, allowing for the combination of TMB status with markers of hypoxia in future clinical applications. Conclusions Hypoxia is an independent prognostic factor and a strong immune infiltration indicator in gastrointestinal tumors of different organs, especially for cancers with low TMB.
Foreign Demand Shocks to Production Networks: Firm Responses and Worker Impacts

We quantify and explain the firm responses and worker impacts of foreign demand shocks to domestic production networks. To capture that firms can be indirectly exposed to such shocks by buying from or selling to domestic firms that import or export, we use Belgian data with information on both domestic firm-to-firm sales and foreign trade transactions. Our estimates of firm responses suggest that Belgian firms pass on a large share of a foreign demand shock to their domestic suppliers, face upward-sloping labor supply curves, and have sizable fixed overhead costs in labor. Motivated and guided by these findings, we develop and estimate an equilibrium model that allows us to study how idiosyncratic and aggregate changes in foreign demand propagate through a small open economy and affect firms and workers. Our results suggest that the way the labor market is typically modeled in existing research on foreign demand shocks—with no fixed costs and perfectly elastic labor supply—would grossly understate the decline in real wages due to an increase in foreign tariffs. Emmanuel Dhyne National Bank of Belgium Boulevard de Berlaimont, 14 1000 Brussels Belgium emmanuel.dhyne@nbb.be Ayumu Ken Kikkawa Sauder School of Business 2053 Main Mall Vancouver, BC Canada ken.kikkawa@sauder.ubc. ca Toshiaki Komatsu Kenneth C. Griffin Department of Economics University of Chicago 5757 South University Avenue Chicago, IL 60637 komatsu@uchicago.edu Magne Mogstad Department of Economics University of Chicago 1126 East 59th Street Chicago, IL 60637 and NBER magne.mogstad@gmail.com Felix Tintelnot Kenneth C. Griffin Department of Economics University of Chicago 5757 South University Avenue Chicago, IL 60637 and NBER tintelnot@uchicago.edu
Trajectory Design for Multi-UAV-Aided Wireless Power Transfer toward Future Wireless Systems

In this paper, we investigate an unmanned aerial vehicle (UAV)-assisted wireless power transfer (WPT) system, in which a set of UAV-mounted mobile energy transmitters (ETs) are dispatched to broadcast wireless energy to an energy receiver (ER) on the ground. In particular, we aim to maximize the amount of energy transferred to the ER during a finite UAV’s flight period, subject to the UAV’s maximum speed and collision avoidance constraints. First, the basic one/two-UAV scenarios are researched in detail, which show that UAVs should hover at fixed locations during the whole charging period. Specifically, the Lagrange multiplier method is employed to solve the proposed optimization problem for the case of two UAV situation. Specifically, the general conclusions based on the theoretical analysis of one/two-UAV scenarios are drawn contribute to deducing the trajectory design of UAVs when the number of UAVs increases from three to seven. The obtained trajectory solution implies that UAVs should be evenly distributed on the circumference with point (0,0,H) as the center and UAVs’ safe distance as the radius. Finally, numerical results are provided to validate the trajectory design algorithm for the multiple UAVs-enabled single-user WPT system.
How Can Companies Recover from Liability-Invoking Failures? Exploring the Role of Uncertainty Avoidance in Facilitating Consumer Compliance Across National Cultures

A company often faces incidents in which its offerings cause bodily (e.g., product safety defects) or psychological (e.g., data breach) harm to its consumers. Such incidents may invoke product liability lawsuits against the company. The company may try to recover from the liability-invoking failure by notifying the affected consumers, offering a remedy, and persuading them to comply with the company message. The authors theorize and experimentally demonstrate that, on average, a prevention-focused message receives greater compliance than a promotion-focused message. Further, a prevention-focused message is more effective with consumers from high-uncertainty-avoidance cultures, whereas a promotion-focused message is more effective in low-uncertainty-avoidance cultures. Perceived compatibility of prevention or promotion goals with low or high values of uncertainty avoidance mediates the interaction effect on compliance. The findings can help companies overcome consumer apathy to product recall or data breach notices and offer managers ways to promote consumer safety and protection.