Miracle-dz/UniFAR-FTUs huggingface dataset:
Accessibility versus Action-Centeredness in the Representation of Cognitive Skills

We believe that the distinction between procedural and declarative knowledge unnecessarily confounds two issues: action-centeredness and accessibility, and can be made clearer through separating the two aspects. The work presents an integrated model of skill learning that takes into account both implicit and explicit processes and both action-centered and non-action-centered knowledge. We examine and simulate human data in the Letter Counting task. The work shows how the data may be captured using either the action-centered knowledge alone or the combined action-centered and non-action-centered knowledge. The results provide a new perspective on skill learning.
Motion detection based fine grained place extraction on mobile cellular phone

Location-based services (LBS) are proliferating in the field of mobile and pervasive computing. Normally, locations are expressed as coordinates or landmarks, which are geography related and hardly to be understood by average user. Recent researches pay much attention to extracting personally meaningful places where one works, lives or plays, using mobile phone as the platform. With the advantages of universal availability and low energy consumption, Global System for Mobile Communication (GSM) based method is more attractive than using GPS or Wi-Fi. However, because of large coverage and overlap of cells, existing methods can only extract coarse grained places and have a limit capability to discriminate the places closed with each other. This paper proposes a motion detection based fine grained place extraction method to discover meaningful places for individual user using GSM information. The proposed method can detect the user's motion states through analyzing the fluctuation of GSM received signal strength (RSS) and divide the cell trace into moving segments and stationary segments. Each stationary segment is represented as a time-weighted cell ID vector, which can confine the places to a small area. Experimental results indicate that the proposed method has strong capability to discriminate places closed with each other and, compared with existing method, extract finer grained places.
Artificial grammar learning meets formal language theory: an overview

Formal language theory (FLT), part of the broader mathematical theory of computation, provides a systematic terminology and set of conventions for describing rules and the structures they generate, along with a rich body of discoveries and theorems concerning generative rule systems. Despite its name, FLT is not limited to human language, but is equally applicable to computer programs, music, visual patterns, animal vocalizations, RNA structure and even dance. In the last decade, this theory has been profitably used to frame hypotheses and to design brain imaging and animal-learning experiments, mostly using the ‘artificial grammar-learning’ paradigm. We offer a brief, non-technical introduction to FLT and then a more detailed analysis of empirical research based on this theory. We suggest that progress has been hampered by a pervasive conflation of distinct issues, including hierarchy, dependency, complexity and recursion. We offer clarifications of several relevant hypotheses and the experimental designs necessary to test them. We finally review the recent brain imaging literature, using formal languages, identifying areas of convergence and outstanding debates. We conclude that FLT has much to offer scientists who are interested in rigorous empirical investigations of human cognition from a neuroscientific and comparative perspective.
Implications of the central metal abundance peak in cooling core clusters of galaxies

Recent XMM-Newton observations of clusters of galaxies have provided detailed information on the distribution of heavy elements in the central regions of clusters with cooling cores providing strong evidence that most of these metals come from recent SN type Ia. In this paper we compile information on the cumulative mass profiles of iron, the most important metallicity tracer. We find that long enrichment times (≥5 Gyr) are necessary to produce the central abundance peaks. Classical cooling flows, a strongly convective intracluster medium, and a complete metal mixing by cluster mergers would destroy the observed abundance peaks too rapidly. Thus the observations set strong constraints on cluster evolution models requiring that the cooling cores in clusters are preserved over very long times. We further conclude from the observations that the innermost part of the intracluster medium is most probably dominated by gas originating predominantly from stellar mass loss of the cD galaxy.
4-26-2012 ON THE FRAGILITY OF HIGH-DIMENSIONAL CONTROLLERS

In this paper we study the fragility of controllers designed to optimize some performance indices. We trace the fragility problem to the dimension of the resulting controllers, and use results from high-dimensional geometry to analyze the problem both in the continuous and discrete domains. One of the purposes of this paper is to understand the effects of uncertainties in the implementation of controllers which optimize some performance and robustness criteria in ∗The research of C.T. Abdallah is partially supported by Boeing Computer Services Grant 3-48181, and by ISTEC
Determination of the decay exponent in mechanically stirred isotropic turbulence

Direct numerical simulation is used to investigate the decay exponent of isotropic homogeneous turbulence over a range of Reynolds numbers sufficient to display both high and low Re number decay behavior. The initial turbulence is generated by the stirring action of the flow past many small randomly placed cubes. Stirring occurs at 1/30th of the simulation domain size so that the low-wavenumber and large scale behavior of the turbulent spectrum is generated by the fluid and is not imposed. It is shown that the decay exponent in the resulting turbulence matches the theoretical predictions for a k2 low-wavenumber spectrum at both high and low Reynolds numbers. The transition from high Reynolds number behavior to low Reynolds number behavior occurs relatively abruptly at a turbulent Reynolds number of around 250 ( Re λ≈41).
Grasp compliance regulation in synergistically controlled robotic hands with VSA

In this paper, we propose a general method to achieve a desired grasp compliance acting both on the joint stiffness values and on the hand configuration, also in the presence of restrictions caused by synergistic underactuation. The approach is based on the iterative exploration of the equilibrium manifold of the system and the quasi-static analysis of the governing equations. As a result, the method can cope with large commanded variations of the grasp stiffness with respect to an initial configuration. Two numerical examples are illustrated. In the first one, a simple 2D hand is analyzed so that the obtained results can be easily verified and discussed. In the second one, to show the method at work in a more realistic scenario, we model grasp compliance regulation for a DLR/HIT hand II grasping a ball.
Modeling clouds shape

We propose a model for representing the shape of cumulus clouds. We draw on several approaches that we combine and extend: We store a hierarchy of quasi-spherical particles (or blobs) living on top of each other. The shape of these particles is dened by an implicit eld which deforms under the inuence of neighbor particles. We dene a set of shaders to simulate a volumetric appearance in the spirit of Gardner’s textured ellipsoids, to make the shape appear continuous, and to account for dedicated shading effects. In this paper we deal only with the denition of the shape. However, we believe that this model is well suited to be integrated with particle animation and advanced rendering.
Direct Measurements of Presynaptic Calcium and Calcium-Activated Potassium Currents Regulating Neurotransmitter Release at CulturedXenopus Nerve–Muscle Synapses

The understanding of neurotransmitter release at vertebrate synapses has been hampered by the paucity of preparations in which presynaptic ionic currents and postsynaptic responses can be monitored directly. We used cultured embryonic Xenopusneuromuscular junctions and simultaneous pre- and postsynaptic patch-clamp current-recording procedures to identify the major presynaptic conductances underlying the initiation of neurotransmitter release. Step depolarizations and action potential waveforms elicited Na and K currents along with Ca and Ca-activated K (KCa) currents. The onset ofKCa current preceded the peak of the action potential. The predominantly ω-CgTX GVIA-sensitive Ca current occurred primarily during the falling phase, but there was also significant Ca2+ entry during the rising phase of the action potential. The postsynaptic current began a mean of 0.7 msec after the time of maximum rate of rise of the Ca current. ω-CgTX also blocked KCa currents and transmitter release during an action potential, suggesting that Ca andKCa channels are colocalized at presynaptic active zones. In double-ramp voltage-clamp experiments,KCa channel activation is enhanced during the second ramp. The 1 msec time constant of decay of enhancement with increasing interpulse interval may reflect the time course of either the deactivation of KCa channels or the diffusion/removal of Ca2+ from sites of neurotransmitter release after an action potential.
Temporal analysis of API usage concepts

Software reuse through Application Programming Interfaces (APIs) is an integral part of software development. The functionality offered by an API is not always accessed uniformly throughout the lifetime of a client program. We propose Temporal API Usage Pattern Mining to detect API usage patterns in terms of their time of introduction into client programs. We detect concepts as distinct groups of API functionality from the change history of a client program. We locate those concepts in the client change history and detect temporal usage patterns, where a pattern contains a set of concepts that were added into the client program in a specific temporal order. We investigated the properties of temporal API usage patterns through a multiple-case study of three APIs and their use in up to 19 client software projects. Our technique was able to detect a number of valuable patterns in two out of three of the APIs investigated. Further investigation showed some patterns to be relatively consistent between clients, produced by multiple developers, and not trivially derivable from program structure or API documentation.
Automated Support for Dynamic Information Distribution in Incident Management

For all emergency response personnel involved in crisis situations it is essential to timely acquire all information critical to their task performance. However, in practice errors occur in the distribution of information between these collaborating actors leading to mistakes and subsequently more damage to the situation. In this paper we present a prototype system for dynamic information distribution able to support the information flow between collaborating crisis actors. The system has been evaluated by means of simulated experiments that use data from a real incident scenario. The results indicate that automated support by means of Machine Learning method works well. Especially, when actor work context features are included, then the performance on selecting and distributing relevant information is high. Furthermore, actors acquire relevant information much faster making group communication much more efficient.
On the exploitation of process mining for security audits: the process discovery case

This paper reports on the potential of process mining as a basis for security audits of business process and corresponding business process management systems. In particular, it focuses on process discovery as a means to reconstruct process-related structures from event logs, such as the process' control flow, social network and data flows. Based on this information, security analysis to determine the compliance with security and privacy requirements can be automated.
Discrete tensorial quasi-harmonic maps

We introduce new linear operators for surface parameterization. Given an initial mapping from the parametric plane onto a surface mesh, we establish a secondary map from the plane onto itself that mimics the initial one. The resulting low-distortion parameterization is smooth as it stems from solving a quasi-harmonic equation. Our parameterization method is robust and independent of (the quality of) the initial map.
A Framework for Permission Recommendation and Risk Evaluation Based on Skewness-Based Filtering

Android mobile ecosystem has penetrated into people's every aspect of life. Since more and more sensitive and valuable information is stored in mobile ecosystem, how to configure the permission system to guarantee the security becomes an important issue for the whole community. In order to solve the permission over-privilege problem, a skewness-based permission recommendation framework is presented to identify the over-privilege permission and evaluate the risk for the Android Apps. Specially, the topic model Latent Dirichlet Allocation is employed to build the mapping between functionality and permission. Considering the fact that even the popular applications violate the least privilege principle, a collaborative filtering variant method in which high risk applications and permissions are identified is presented to recommend required permissions. Finally, the permission over-privilege based ap-proach is presented to evaluate the risk of the application. The experiments based on the Apps from Google Play shows that our approach is effective to identify the unexpected permissions for both popular and malicious Apps.
The Cosmological properties of AGN in the XMM-Newton Hard Bright Survey

Aims. We investigate here the X-ray luminosity function (XLF) of absorbed (NH between 4 × 10 21 and 10 24 cm −2 ) and unabsorbed (NH 10 24 cm −2 ) AGN. Methods. To carry out this investigation, we have used the XMM-Newton Hard Bright Serendipitous Sample (HBSS), a complete sample of bright X-ray sources (fx > 7 × 10 −14 erg cm −2 s −1 ) at high galactic latitude (|b| > 20 ◦ ) selected in the 4.5−7.5 keV energy band. The HBSS sample is now almost completely identified (97% spectroscopic identifications) and it can be safely used for a statistical investigation. The HBSS contains 62 AGN out of which 40 are unabsorbed (or marginally absorbed; NH 3 × 10 42 erg s −1 is 0.57 ± 0.11; we find that F decreases with the intrinsic luminosity, and probably, increases with the redshift. Our data are consistent with a flat Log NH distribution for NH between 10 20 and 10 24 cm −2 . Finally, by comparing the results obtained here with those obtained using an optically-selected sample of AGN we derive, in an indirect way, the XLF of Compton thick AGN; the latter is well described by a XLF similar, in shape, to that of absorbed AGN, but having a normalization of about a factor of 2 above. The density ratio between Compton thick AGN (NH ≥ 10 24 cm −2 )a nd Compton thin AGN (NH ≤ 10 24 cm −2 ) decreases from 1.08 ± 0.44 at ∼10 43 erg s −1 to 0.57 ± 0.22 at ∼10 44 erg s −1 to 0.23 ± 0.15 at ∼10 45 erg s −1 . Conclusions. The results presented here on the anti-correlation between F and −Lx are fully consistent with the hypothesis of a reduction of the covering factor of the gas as a function of the luminosity and are clearly inconsistent with the simplest unified scheme of AGN. These results strongly support the recently proposed radiation-limited clumpy dust torus model although alternative physical models are also consistent with the observations.
An efficient AlGaN/GaN HEMT power amplifier MMIC at K-Band

This paper presents an efficient power amplifier MMIC at K-Band (20 GHz) designed for a 0.25 μm AlGaN/GaN HEMT process on three-inch s.i. -SiC substrates. A low-loss network topology is used for second-harmonic output matching to achieve high PAE. The measured amplifier has a maximum PAE of 41% and an associated output power of 31.4dBm when operated at a drain voltage of 20V. At 35V drain voltage, the amplifier exhibits a PAE of 34% and an associated output power of 34 dBm.
Toward Designing Efficient Application to Identify Objects for Visually Impaired

There is an increasing interest in developing technologies that attempt to help visually impaired people in their daily lives. However, it is shown that the object identification task is still the major difficulty for visually impaired people. Although there are many applications that can be used for this task, there are still obvious limitations that require more improving. For this reason, this paper provides an analysis and evaluation for the technologies that used in the object identification task. As a result of this evaluation, it is shown that the best technology is the human computation. Moreover, a comparison between the applications that use human computation is provided in order to identify the best features that can be considered in designing efficient application to identify objects for visually impaired.
A Finite Element Flux-Corrected Transport Method for Wave Propagation in Heterogeneous Solids

When moving discontinuities in solids need to be simulated, standard finite element (FE) procedures usually attain low accuracy because of spurious oscillations appearing behind the discontinuity fronts. To assure an accurate tracking of traveling stress waves in heterogeneous media, we propose here a flux-corrected transport (FCT) technique for structured as well as unstructured space discretizations. The FCT technique consists of post-processing the FE velocity field via diffusive/antidiffusive fluxes, which rely upon an algorithmic length-scale parameter. To study the behavior of heterogeneous bodies featuring compliant interphases of any shape, a general scheme for computing diffusive/antidiffusive fluxes close to phase boundaries is proposed too. The performance of the new FE-FCT method is assessed through one-dimensional and two-dimensional simulations of dilatational stress waves propagating along homogeneous and composite rods.
The Oligodendroglial Lineage Marker OLIG2 Is Universally Expressed in Diffuse Gliomas

Astrocytomas, oligodendrogliomas, and oligoastrocytomas, collectively referred to as diffuse gliomas, are the most common primary brain tumors. These tumors are classified by histologic similarity to differentiated astrocytes and oligodendrocytes, but this approach has major limitations in guiding modern treatment and research. Lineage markers represent a potentially useful adjunct to morphologic classification. The murine bHLH transcription factors Olig1 and Olig2 are expressed in neural progenitors and oligodendroglia and are essential for oligodendrocyte development. High OLIG expression alone has been proposed to distinguish oligodendrogliomas from astrocytomas, so we critically evaluated OLIG2 as a marker by immunohistochemical and oligonucleotide microarray analysis. OLIG2 protein is faithfully restricted to normal oligodendroglia and their progenitors in human brain. Immunohistochemical analysis of 180 primary, metastatic, and non-neural human tumors shows OLIG2 is highly expressed in all diffuse gliomas. Immunohistochemistry and microarray analyses demonstrate higher OLIG2 in anaplastic oligodendrogliomas versus glioblastomas, which are heterogeneous with respect to OLIG2 levels. OLIG2 protein expression is present but inconsistent and generally lower in most other brain tumors and is absent in non-neuroectodermal tumors. Overall, OLIG2 is a useful marker of diffuse gliomas as a class. However, expression heterogeneity of OLIG2 in astrocytomas precludes immunohistochemical classification of individual gliomas by OLIG2 alone.
Work in Progress - an approach for mapping of auto generated questions to related topics in the curriculum

Questions are essential components for assessment of learners' knowledge in teaching - learning environments. The questions should be developed related to tasks of the instructional objectives associated with a learning object. It is expected that a given set of question will cover maximum possible topics under an instructional objective. By analyzing the response to these questions, instructors are able to identify the strong and weak areas of a learner, and are able to understand the deficiency in learning and provide solution for overcoming it. However if the system generates automated questions, a given set of questions may or may not cover all the topics given in the learning object. To identify the amount of topic that is covered under a given set of question, we first use phrase mining technique and then do topic modeling on text data of the given set of questions. By mining the words present the phrases of the individual question stem, we can identify the keywords, calculate its significance value and identify the most appropriate topic it relates to.
How Evolution of Genomes Is Reflected in Exact DNA Sequence Match Statistics

Genome evolution is shaped by a multitude of mutational processes, including point mutations, insertions, and deletions of DNA sequences, as well as segmental duplications. These mutational processes can leave distinctive qualitative marks in the statistical features of genomic DNA sequences. One such feature is the match length distribution (MLD) of exactly matching sequence segments within an individual genome or between the genomes of related species. These have been observed to exhibit characteristic power law decays in many species. Here, we show that simple dynamical models consisting solely of duplication and mutation processes can already explain the characteristic features of MLDs observed in genomic sequences. Surprisingly, we find that these features are largely insensitive to details of the underlying mutational processes and do not necessarily rely on the action of natural selection. Our results demonstrate how analyzing statistical features of DNA sequences can help us reveal and quantify the different mutational processes that underlie genome evolution.
Development of a scale to measure gamer experiences in sport video games

The aim of this study is to develop a scale to measure gamer experiences in sport video games. A two-phase data analysis was conducted with 400 respondents randomly assigned to one of two phases. In each phase, respondents were tasked to play a sports car racing game and complete a survey instrument. The study identified six dimensions of sports video games based on gamer experience. These are challenge, competence, flow, immersion, enjoyment and negative affect. Using this scale, it will be possible to examine differences in gamer experience across sports video games. More importantly, it will be possible to examine the relationship between gamer experience and sponsorship effectiveness in future studies using this scale.
On the Accuracy of Explicit Finite-Volume Schemes for Fluctuating Hydrodynamics

Aleksandar Donev,1, ∗ Eric Vanden-Eijnden,2 Alejandro L. Garcia,3 and John B. Bell4 Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-9900 Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 Department of Physics, San Jose State University, San Jose, California, 95192 Center for Computational Science and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720