Miracle-dz/UniFAR-FTUs huggingface dataset:
Automatic question classification models for computer programming examination: A systematic literature review

A test is the commonest method to evaluate the progress and potential of candidates in any field, especially in academic fields. In the academic field, exams help evaluate the understanding, applicative ability, and retainable knowledge of a student. Therefore, the questions need to be suitably set, so that all these areas can be judged. The results of these tests help determine if the student is fit for the next level of education. Setting the right question paper is a major challenge for the teachers concerned. The current study aims to analyze the ongoing question classification models with reference to the set of formulated research questions. In order to locate question classification models, relevant keywords were used in the search terms. A set of nine different studies were picked from the search processes. In the studies, 4 stands for journal articles, and 5 stands for conference papers. Question classification has been discussed in the computing domain, especially with respect to computer programming assessment. A more extensive examination of this classification reveals quite a few shortcomings of the prevailing classification methods. These include the absence of suitable taxonomy for computer programming questions, limitation in approaches to handle multi-labelling, and a need for methods compatible to tackle code-mixed question classification. Furthermore, the necessity to develop advanced hybrid feature selection methods in order to enhance the classification performance.
Design, analysis, and optimization of radio frequency front-ends for integrated wireless receivers

Monograph Article dissertation (summary + original articles) Department Laboratory Field of research Opponent(s) Supervisor (Instructor) Abstract Keywords radio frequency, radio receiver, direct conversion, low-noise amplifier, downconversion mixer Design, analysis, and optimization of radio frequency front-ends for integrated wireless receivers X This thesis consists of six publications and an overview of the research topic, which is also a summary of the work. The research described in this thesis is focused on the design, analysis, and optimization of RF front-ends for wireless zero-and low-IF receivers. The main interest of the work is in the 1-4 GHz range and in CMOS and BiCMOS technologies. Often, the RF front-end limits the performance of the entire direct conversion or low-IF radio receiver. The emphasis in this work is on the challenges posed by mass production for the design of integrated RF circuits. Thus, the effects of packaging and ESD protection on the LNA performance are analyzed and circuit optimization and design methods for the packaged LNAs are examined. This thesis also studies circuit techniques for the stabilization of the RF front-end performance against process and temperature variations. For this purpose, a gain stabilization technique for tuned LNAs is proposed. By applying the proposed method, the voltage gain variation of the inductively degenerated LNA, which is the most popular LNA architecture, is shown to be reduced several decibels. As a consequence, the radio receiver can more easily meet its specifications in the presence of IC process variations and the product yield is thereby improved. To improve the IIP2 of the mixer, a circuit technique for the cancellation of the second-order intermodulation distortion in downconversion mixer RF input stages is proposed. The presented method is shown to improve the yield of the radio receiver by reducing the IIP2 sensitivity to mismatches and offsets. Low supply voltage and low-frequency flicker noise present in sub-micron CMOS processes pose challenges for the design of direct conversion RF front-ends, especially for narrow-band systems such as GSM. However, since the development of low-voltage CMOS analog and RF circuits is economically advantageous, the design and optimization of low-voltage CMOS RF front-ends are studied in this work. The work summarizes the design, analysis, and optimization of several RF front-ends, LNAs, and mixers. One of the implemented RF front-ends is integrated with an on-chip VCO as a part of larger direct conversion receiver chip. One is realized with an on-chip VCO as a standalone RF …
The Ancient Romans’ Route to Charge Density Waves in Cuprates

An account is given of the main steps that led the research group in Rome, to which the author belongs, to the formulation of the charge-density-wave scenario for high- T c superconducting cuprates. The early finding of the generic tendency of strongly correlated electron systems with short range interactions to undergo electron phase separation was subsequently contrasted with the homogenizing effect of the long-range Coulomb interaction. The two effects can find a compromise in the formation of incommensurate charge density waves. These charge density waves are inherently dynamical and are overdamped as a consequence of the possibility to decay in electron-hole pairs, yet tend to maintain a (quantum) critical character, which is mirrored in their marked momentum and frequency dependence and in their strong variation with temperature and doping. These dynamical incommensurate charge density waves act as mediators of pairing lading to high- T c superconductivity, and provide the scattering mechanism that produces the observed violation of the Fermi-liquid paradigm in the metallic phase.
Using adaptively weighted large margin classifiers for robust sufficient dimension reduction

ABSTRACT In this paper, we combine adaptively weighted large margin classifiers with Support Vector Machine (SVM)-based dimension reduction methods to create dimension reduction methods robust to the presence of extreme outliers. We discuss estimation and asymptotic properties of the algorithm. The good performance of the new algorithm is demonstrated through simulations and real data analysis.
Gauge Theories: From Kaluza-Klein to noncommutative gravity theories

First, the Coset Space Dimensional Reduction scheme and the best particle physics model so far resulting from it are reviewed. Then, a higher-dimensional theory in which the extra dimensions are fuzzy coset spaces is described and a dimensional reduction to four-dimensional theory is performed. Afterwards, another scheme including fuzzy extra dimensions is presented, but this time the starting theory is four-dimensional while the fuzzy extra dimensions are generated dynamically. The resulting theory and its particle content is discussed. Besides the particle physics models discussed above, gravity theories as gauge theories are reviewed and then, the whole methodology is modified in the case that the background spacetimes are noncommutative. For this reason, specific covariant fuzzy spaces are introduced and, eventually, the program is written for both the 3-d and 4-d cases.
Recovery processes and dynamics in single and interdependent networks

To my family and good friends, both scattered around the World. Acknowledgments I would like to thank my mentor and thesis advisor, H.E. Stanley. Gene is an institution himself. A great scientist, a perfect advisor and a great friend. In the final version of this draft I will write a luxurious paragraph on him and the five years I spent at BU. I enjoyed so much in his research group. Unfortunately, good things do not always last forever, but hopefully are replaced by other good things in life. I would like to thank my best friend Berislav, for being a person I could call at 3AM in the morning and talk about life, science, or any other topic. I thank him for reading all my papers and this thesis manuscript. He's also a physicist. I would like to thank my other best friend, Boris Podobnik, the funniest guy I know, for doing a great work with research. I miss our dinners at restaurants around Kenmore and BU campus. I thank Shlomo Havlin for being a huge motivator and inspiration, both as a scientist and as a wonderful person. Working with him, I was never afraid of my ideas. William Skocpol and Plamen Ivanov, for their advices and help with my thesis. I thank Tomislav Lipic for discussing my research with me, and teaching me how to code. iv I thank Mirtha Cabello for helping me so many times at BU. When I remember Boston University, a few things come to my mind first, and Mirtha is one of them. Room 101 will long stay in my memory as " home " .
New Results on the Exponential Stability of Class Neural Networks with Time-Varying Lags

In this article, some novel approaches to the analysis of globally exponential stability (GES) for a class of neural networks with time-varying lags are presented. These approaches to functional differential equations are based on Lyapunov stability theory. Then, the necessary and sufficient conditions for GES of the equation taking into account have been discussed. An example was given to illustrate the qualitative behavior of the solution of the proposed equation and MATLAB-Simulink Program was used to demonstrate the validity of the results obtained in these samples. Consequently, the obtained results include and improve the results found in the related literature.
Very-high-energy Emission from Magnetic Reconnection in the Radiative-inefficient Accretion Flow of SgrA*

The cosmic-ray (CR) accelerator at the Galactic center (GC) is not yet established by current observations. Here we investigate the radiative-inefficient accretion flow (RIAF) of Sagittarius A* (SgrA*) as a CR accelerator assuming acceleration by turbulent magnetic reconnection, and derive possible emission fluxes of CRs interacting within the RIAF (the central ∼1013 cm). The target environment of the RIAF is modeled with numerical, general relativistic magnetohydrodynamics together with leptonic radiative transfer simulations. The acceleration of the CRs is not computed here. Instead, we inject CRs constrained by the magnetic reconnection power of the accretion flow and compute the emission/absorption of γ-rays due to these CRs interacting with the RIAF, through Monte Carlo simulations employing the CRPropa 3 code. The resulting very-high-energy (VHE) fluxes are not expected to reproduce the point source HESS J1745-290 as the emission of this source is most likely produced at parsec scales. The emission profiles derived here intend to trace the VHE signatures of the RIAF as a CR accelerator and provide predictions for observations of the GC with improved angular resolution and differential flux sensitivity as those of the forthcoming Cerenkov Telescope Array (CTA). Within the scenario presented here, we find that for mass accretion rates ≳10−7 M⊙yr−1, the RIAF of SgrA* produces VHE fluxes that are consistent with the High Energy Stereoscopic System (H.E.S.S.) upper limits for the GC and potentially observable by the future CTA. The associated neutrino fluxes are negligible compared with the diffuse neutrino emission measured by the IceCube.
Forecasting Conditional Covariance Matrices in High-Dimensional Time Series: A General Dynamic Factor Approach

Abstract Based on a General Dynamic Factor Model with infinite-dimensional factor space and MGARCH volatility models, we develop new estimation and forecasting procedures for conditional covariance matrices in high-dimensional time series. The finite-sample performance of our approach is evaluated via Monte Carlo experiments and outperforms the most alternative methods. This new approach is also used to construct minimum one-step-ahead variance portfolios for a high-dimensional panel of assets. The results are shown to match the results of recent proposals by Engle, Ledoit, and Wolf and achieve better out-of-sample portfolio performance than alternative procedures proposed in the literature.
ANALISIS PENGUASAAN KONSEP SISWA YANG BELAJAR MATERI MOMENTUM DAN IMPULS BERBASIS SCIENTIFIC APPROACH DISERTAI FORMATIVE ASSESSMENT BERBANTUAN WEB

Penguasaan konsep merupakan kemampuan dasar bagi siswa untuk memahami suatu pengetahuan secara baik dan benar. Namun, fakta lapangan menunjukan bahwa penguasaan siswa masih rendah salah satunya pada materi Momentum dan Impuls. Penelitian ini bertujuan untuk menganalisis penguasaan konsep Siswa yang belajar materi momentum dan Impuls berbasis scientific approach disertai formative assessment berbantuan web. Penelitian ini menggunakan metode mixed method dengan desain embedded experimental. Data dari penelitian ini terbagi menjadi dua yaitu data kuantitatif dan kualitatif. Data kuantitatif diperoleh dari skor pretest dan postest sedangkan data kualitatif diperoleh dari observasi, catatan lapangan, dan dokumentasi selama pembelajaran serta wawancara. Subjek penelitian adalah siswa kelas X MIPA 3 MAN 1 Malang yang terdiri dari 38 siswa. Instrumen pengukuran penguasaan konsep diadaptasi dari energy and momentum conceptual survey (EMCS). Data dianalisis dengan paired sample t-test, rata-rata N-gain, dan d-effect size. Data kualitatif dianalisis dengan cara reduksi data, coding, deskripsi dan interprestasi. Hasil penelitian ini menunjukkan bahwa penguasaan konsep siswa yang belajar materi momentum dan impuls Berbasis Scientific Approach disertai formative assessment Berbatuan Web Meningkat. Hasil t-test didapatkan nilai yang signifikan (p = 0,00 < 0,05) antara skor pretest dan postest. Nilai N-gain yang diperoleh sebesar 0,33 yang termasuk kategori medium bawah. Sedangkan, Kekuatan dampak atau keefektivan pembelajaran terhadap penguasaan konsep siswa dilakukan perhitungan d-effect size. Nilai d-effect size sebesar 1,31 yang termasuk dalam kategori tinggi. Hasil wawancara juga diperoleh bahwa siswa mengalami kesulitan dalam memahami konsep Momentum dan Impuls berdasarkan hukum Newton II dan III. Kata kunci: Penguasaan Konsep, Scientific Approach, Formative Assesment
Emotional Testing on Facebook’s User Experience

This study aims at understanding how a user’s emotions fluctuate when undertaking certain tasks on a social media platform such as Facebook or other software products which may have emotional effects on its user. Specifically, we explored the difference in the usability aspect of Facebook concerning frequent and new Facebook users. The study involves a qualitative study on eighteen participants, nine of whom were Facebook users and nine non-Facebook users who had never used Facebook before participating in this study. During the testing procedure, users were asked to complete several tasks on Facebook, while the electrophysiological activity of their brain was recorded using an EEG (electroencephalogram) acquisition system. Certainly, this study can be applied to any software product, before its release, to improve its user interface by acquiring insight into how user-friendly it is for new users when compared to frequent users. Additionally, a correlation in user friendliness between new users and frequent users is investigated. Furthermore, the study will help us discern which parts of the brain had the most significant difference between groups and discuss the motives behind an individual’s emotional state, concerning user experience. Based on the analysis of the power spectrum of the characteristic brain waves, this research establishes that there is a substantial statistical difference between new and frequent Facebook users. Also, it resulted that there is a significant difference between the central, temporal and occipital lobes of new and frequent users. These results will assist developers in creating optimal and user-friendly software products.
New results in N=2 theories from non-perturbative string

We describe the magnetic phase of SU(M) $\mathcal{N}=2$ Super Yang-Mills theories in the self-dual Omega background in terms of a new class of multi-cut matrix models. These arise from a non-perturbative completion of topological strings in the dual four dimensional limit which engineers the gauge theory in the strongly coupled magnetic frame. The corresponding spectral determinants provide natural candidates for the tau functions of isomonodromy problems for flat spectral connections associated to the Seiberg-Witten geometry.
Structures, dipoles and dynamics of large molecules in their excited singlet states

Mittels hochaufgeloster Fluoreszenzspektroskopie konnen verschiedene Molekulparameter isolierter Molekule untersucht werden, welche zur Bestimmung der geometrischen Struktur, sowie der elektronischen Natur des elektronischen Grund- und ersten angeregten Zustands dienen. Dafur wurden im Rahmen dieser Arbeit die verschiedenen Rotamere von 1,2-, 1,3- und 1,4-Dimethoxybenzol sowie 4-Cyanoindol und dessen Wassercluster untersucht. Ein Teil dieser Arbeit beschaftigte sich mit der Untersuchung des Konformerenraums von 1,3-Dimethoxybenzol. Dabei wurden die intensivsten Schwingungsbanden von 1,3-Dimethoxybenzol rotationsaufgelost untersucht und anhand der Rotationskonstanten den verschiedenen Rotameren zugeordnet. Es wurde eines der drei moglichen planaren Rotameren nicht gefunden und die vermutete Ursprungsbande eines Rotamers stellte sich als eine Schwingungsbande eines anderen Rotamers heraus. Das nicht gefundene Rotamer hat die Struktur bei der beide Methoxygruppen parallel nach oben zeigen. Weitere Untersuchungen anhand von quantenchemischen Rechnungen zeigten, dass das Rotamer aufgrund seiner nicht planaren Geometrie im elektronisch angeregten Zustand und eines daraus folgenden niedrigen Franck-Condon-Faktors eine zu geringe Intensitat hat, um untersucht zu werden. Eine ahnliche Beobachtung wurde bereits bei der Untersuchung des Konformerenraums von 1,3-Methoxyphenol gemacht. Die Ergebnisse hierzu sind in Kapitel 5 detailliert aufgefuhrt. In Kapitel 6, welches sich mit den Dipolmomenten der drei Konstitutionsisomere von Dimethoxybenzol beschaftigt, wurden die Dipolmomente mittels Vektoraddition hergeleitet und mit den experimentellen Ergebnissen verglichen. Dabei zeigte sich, dass die Vektoraddition gut fur den elektronischen Grundzustand funktioniert. Fur den ersten elektronisch angeregten Zustand funktioniert diese Methode nur fur asymmetrische und nicht fur symmetrische Molekule. Dieses Verhalten konnte auf eine Mischung der Zustande fur asymmetrische Molekule zuruckgefuhrt werden. Weiter wurde 3-Cyanoindol und das 3-Cyanoindol Wassercluster analysiert. Anhand der Rotationskonstanten konnte das beobachtete Wassercluster eindeutig als die Struktur, bei der das Wassermolekul uber Wasserstoffbruckenbindung an das NH des Indolgerusts gebunden ist, identifiziert werden. Die Analyse der elektronischen Natur des ersten angeregten Zustands zeigte, sowohl fur 3-Cyanoindol als auch fur das Wassercluster, einen Lb-Charakter. Somit findet eine Absenkung des La Zustands unter den Lb Zustand nicht statt, wie es beispielsweise bei 4-Cyanoindol zu beobachten ist. Die Untersuchung der Fluoreszenzlebenszeiten zeigte weiter eine abfallende Lebensdauer vom Monomer zum Wassercluster und eine auserst kurze in wassriger Losung. Dem steht eine Verlangerung der Fluoreszenzlebensdauer bei Deuterierung der NH Position gegenuber.
On mixed dynamics of two-dimensional reversible diffeomorphisms with symmetric non-transversal heteroclinic cycles

We consider one-parameter families (general unfoldings) of two-dimensional reversible diffeomorphisms that contain a diffeomorphism with a symmetric non-transversal heteroclinic cycle. We show that in such families there exist Newhouse intervals of parameters such that the values corresponding to the co-existence of infinitely many stable, completely unstable, saddle and symmetric elliptic periodic orbits are generic (that is, they form Baire second-category sets). Also, the closures of the sets of orbits of different types have non-empty intersections.
THE BUS TRANSPORTATION SERVICE WEBSITES QUALITY PERCEPTION BY STUDENTS IN GREATER AGADIR: EXPLORATORY STUDY.

Hnaka Zainab 1 , Souaf Malika 1 and Amajid Ghizlane 2 . 1. Professor Researcher, EMAPES, ENCG, University Ibn Zohr, Agadir, Morocco. 2. Doctor in management sciences, EMAPES, ENCG, University Ibn Zohr, Agadir, Morocco. Manuscript Info Abstract . Manuscript History Received: 15 March 2019 Final Accepted: 17 April 2019 Published: May 2019
Alteration assemblages in the nakhlites: Variation with depth on Mars

Secondary mineral assemblages in the nakhlite meteorites, Lafayette, Governador Valadares (GV), Nakhla, Yamato (Y)‐000593/Y‐000749 have been studied using scanning electron microscopy, transmission electron microscopy, and electron probe micro analysis. The different nakhlites have distinctive secondary assemblages in their olivine grains and mesostases, showing compositional fractionation correlated with their relative depths below the Martian surface. Fracture‐filled veins in Lafayette at the bottom of the pile consist of a siderite‐phyllosilicate‐Fe oxide‐hydrated silicate gel assemblage. Corresponding veins in Nakhla and GV further up the pile are predominantly a siderite‐gel assemblage, with additional evaporites including gypsum. Y‐000593/Y‐000749 veins are dominated by gel. The gel’s Mg/(Mg + Fe) ratio decreases from Lafayette (0.37) to GV (0.32), Nakhla (0.24), and Y‐000593 (0.15). We suggest that hydrothermal fluid flowed up this depth profile, initiated by melting of buried H2O–CO2 ice. Our results show a complex mix of Fe‐rich phyllosilicate within the veins and mesostasis of Lafayette with d‐spacings of 0.7–1.1 nm suggesting a mixture of smectite and serpentine. The phyllosilicate formed at close to neutral pH, ≤150 °C. We also suggest that water rock ratios (W/R) of 1–10 occurred in Lafayette with smaller values for the other nakhlites. This is reflected in the volume of alteration minerals: 10% of olivine in Lafayette to 3% in Nakhla. Textural evidence of rapid cooling, together with the W/R and likely fluid velocities, suggest that the secondary assemblages formed quickly, e.g., within months. A model is proposed in which the secondary assemblages formed in an impact‐induced hydrothermal system terminated by precipitation of the gel and evaporation of soluble salts.
Pre-processing technique for wireless capsule endoscopy image enhancement

Wireless capsule endoscopy (WCE) is used to examine human digestive tract in order to detect abnormal area. However, it has been a challenging task to detect abnormal area such as bleeding due to poor quality and dark images of WCE. In this paper, pre-processing technique is introduced to ease classification of the bleeding area. Anisotropic contrast diffusion method is employed in our pre-processing technique as a contrast enhancement of the images. There is a drawback to the method proposed B. Li in which the quality of WCE image is degraded when the number of iteration increases. To solve this problem, variance is employed in our proposed method. To further enhance WCE image, Discrete Cosine Transform is used with anisotropic contrast diffusion. Experimental results show that both proposed contrast enhancement algorithm and sharpening WCE image algorithm provide better performance compared with B. Li’s algorithm since SDME and EBCM value is stable whenever number of iterations increases, and sharpness measurement using gradient and PSNR are both improved by 31.5% and 20.3% respectively.