20,214 research outputs found
FLAX: Flexible and open corpus-based language collections development
In this case study we present innovative work in building open corpus-based language collections by focusing on a description of the opensource multilingual Flexible Language Acquisition (FLAX) language project, which is an ongoing example of open materials development practices for language teaching and learning. We present language-learning contexts from across formal and informal language learning in English for Academic Purposes (EAP). Our experience relates to Open Educational Resource (OER) options and Practices (OEP) which are available for developing and distributing online subject-specific language materials for uses in academic and professional settings. We are particularly concerned with closing the gap in language teacher training where competencies in materials development are still dominated by print-based proprietary course book publications. We are also concerned with the growing gap in language teaching practitioner competencies for understanding important issues of copyright and licencing that are changing rapidly in the context of digital and web literacy developments. These key issues are being largely ignored in the informal language teaching practitioner discussions and in the formal research into teaching and materials development practices
On the Reverse Engineering of the Citadel Botnet
Citadel is an advanced information-stealing malware which targets financial
information. This malware poses a real threat against the confidentiality and
integrity of personal and business data. A joint operation was recently
conducted by the FBI and the Microsoft Digital Crimes Unit in order to take
down Citadel command-and-control servers. The operation caused some disruption
in the botnet but has not stopped it completely. Due to the complex structure
and advanced anti-reverse engineering techniques, the Citadel malware analysis
process is both challenging and time-consuming. This allows cyber criminals to
carry on with their attacks while the analysis is still in progress. In this
paper, we present the results of the Citadel reverse engineering and provide
additional insight into the functionality, inner workings, and open source
components of the malware. In order to accelerate the reverse engineering
process, we propose a clone-based analysis methodology. Citadel is an offspring
of a previously analyzed malware called Zeus; thus, using the former as a
reference, we can measure and quantify the similarities and differences of the
new variant. Two types of code analysis techniques are provided in the
methodology, namely assembly to source code matching and binary clone
detection. The methodology can help reduce the number of functions requiring
manual analysis. The analysis results prove that the approach is promising in
Citadel malware analysis. Furthermore, the same approach is applicable to
similar malware analysis scenarios.Comment: 10 pages, 17 figures. This is an updated / edited version of a paper
appeared in FPS 201
Giant Electron-hole Charging Energy Asymmetry in Ultra-short Carbon Nanotubes
Making full usage of bipolar transport in single-wall carbon nanotube (SWCNT)
transistors could permit the development of two-in-one quantum devices with
ultra-short channels. We report on clean 10 to 100 nm long suspended
SWCNT transistors which display a large electron-hole transport asymmetry. The
devices consist of naked SWCNT channels contacted with sections of
SWCNT-under-annealed-gold. The annealed gold acts as an n-doping top gate which
creates nm-sharp barriers at the junctions between the contacts and naked
channel. These tunnel barriers define a single quantum dot (QD) whose charging
energies to add an electron or a hole are vastly different ( charging
energy asymmetry). We parameterize the transport asymmetry by the ratio
of the hole and electron charging energies . We show that this
asymmetry is maximized for short channels and small band gap SWCNTs. In a small
band gap SWCNT device, we demonstrate the fabrication of a two-in-one quantum
device acting as a QD for holes, and a much longer quantum bus for electrons.
In a 14 nm long channel, reaches up to 2.6 for a device with a
band gap of 270 meV. This strong transport asymmetry survives even at
room temperature
Modelling and validation of off-road vehicle ride dynamics
Increasing concerns on human driver comfort/health and emerging demands on suspension systems for off-road vehicles call for an effective and efficient off-road vehicle ride dynamics model. This study devotes both analytical and experimental efforts in developing a comprehensive off-road vehicle ride dynamics model. A three-dimensional tire model is formulated to characterize tire–terrain interactions along all the three translational axes. The random roughness properties of the two parallel tracks of terrain profiles are further synthesized considering equivalent undeformable terrain and a coherence function between the two tracks. The terrain roughness model, derived from the field-measured responses of a conventional forestry skidder, was considered for the synthesis. The simulation results of the suspended and unsuspended vehicle models are derived in terms of acceleration PSD, and weighted and unweighted rms acceleration along the different axes at the driver seat location. Comparisons of the model responses with the measured data revealed that the proposed model can yield reasonably good predictions of the ride responses along the translational as well as rotational axes for both the conventional and suspended vehicles. The developed off-road vehicle ride dynamics model could serve as an effective and efficient tool for predicting vehicle ride vibrations, to seek designs of primary and secondary suspensions, and to evaluate the roles of various operating conditions
Valuation Perspectives and Decompositions for Variable Annuities with GMWB riders
The guaranteed minimum withdrawal benefit (GMWB) rider, as an add on to a
variable annuity (VA), guarantees the return of premiums in the form of peri-
odic withdrawals while allowing policyholders to participate fully in any
market gains. GMWB riders represent an embedded option on the account value
with a fee structure that is different from typical financial derivatives. We
consider fair pricing of the GMWB rider from a financial economic perspective.
Particular focus is placed on the distinct perspectives of the insurer and
policyholder and the unifying relationship. We extend a decomposition of the VA
contract into components that reflect term-certain payments and embedded
derivatives to the case where the policyholder has the option to surrender, or
lapse, the contract early.Comment: 18 pages, proof of Lemma A.1 expanded for clarit
Somatization vs. Psychologization of Emotional Distress: A Paradigmatic Example for Cultural Psychopathology
This paper describes the developing area of cultural psychopathology, an interdisciplinary field of study focusing on the ways in which cultural factors contribute to the experience and expression of psychological distress. We begin by outlining two approaches, often competing, in order to provide a background to some of the issues that complicate the field. The main section of the paper is devoted to a discussion of depression in Chinese culture as an example of the types of questions that can be studied. Here, we start with a review of the epidemiological literature, suggesting low rates of depression in China, and move to the most commonly cited explanation, namely that Chinese individuals with depression present this distress in a physical way. Different explanations of this phenomenon, known as somatization, are explored and reconceptualized according to an increasingly important model for cross-cultural psychologists: the cultural constitution of the self. We close by discussing some of the contributions, both theoretical and methodological, that can be made by cross-cultural psychologists to researchers in cultural psychopathology
Advances in the Design and Implementation of a Multi-Tier Architecture in the GIPSY Environment
We present advances in the software engineering design and implementation of
the multi-tier run-time system for the General Intensional Programming System
(GIPSY) by further unifying the distributed technologies used to implement the
Demand Migration Framework (DMF) in order to streamline distributed execution
of hybrid intensional-imperative programs using Java.Comment: 11 pages, 3 figure
The compact support property for the -Fleming-Viot process with underlying Brownian motion
Using the lookdown construction of Donnelly and Kurtz we prove that, at any
fixed positive time, the -Fleming-Viot process with underlying
Brownian motion has a compact support provided that the corresponding
-coalescent comes down from infinity not too slowly. We also find both
upper bound and lower bound on the Hausdorff dimension for the support.Comment: 21 page
All the Groups of Signal Analysis from the (1+1)-affine Galilei Group
We study the relationship between the (1+1)-affine Galilei group and four
groups of interest in signal analysis and image processing, viz., the wavelet
or the affine group of the line, the Weyl-Heisenberg, the shearlet and the
Stockwell groups. We show how all these groups can be obtained either directly
as subgroups, or as subgroups of central extensions of the affine Galilei
group. We also study this at the level of unitary representations of the groups
on Hilbert spaces.Comment: 28 pages, 1 figur
On the location of poles for the Ablowitz-Segur family of solutions to the second Painlev\'e equation
Using a simple operator-norm estimate we show that the solution to the second
Painlev\'e equation within the Ablowitz-Segur family is pole-free in a well
defined region of the complex plane of the independent variable. The result is
illustrated with several numerical examples.Comment: 8 pages, to appear in Nonlinearit
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