Miracle-dz/UniFAR-FTUs huggingface dataset:
The Protocol Independent Detection and Classification (PIDC) system for DRDoS attack

High-rate flooding attack detection and classification has become a necessary component for network administrators due to their attack range that affects the Data Center servers. The main objective of this paper is to propose the Protocol Independent Detection and Classification (PIDC) system in order to prevent the web servers from devastating attacks such as Distributed Reflection Denial of Service (DRDoS) attacks. The DRDoS flooding attack exploits fixed IP spoofing to defeat the Distributed Denial of Service (DDoS) attack prevention measures. This is the first paper to detect and classify the types of reflected attacks using SNMP MIB variables. The proposed PIDC system uses the data mining and machine learning techniques to detect all types of reflected flooding attacks. The rank correlation based detection algorithm retrieves the incoming traffic in the form of Simple Network Management Protocol -Management Information Base (SNMP-MIB) variables and finds the relationship between the MIB variables to detect the attacks from the normal traffic. Then, C4.5 classification algorithm extracts and frames association rule based on protocol information from reflected DDoS flooding attacks. Finally, the CPU, memory and disk resource distribution to legitimate requests are also increased. This method achieves 99% of true positive rates and less false positive rate of (1%) when compared to existing reflected attack detection methods. Moreover, these attacks are classified by types such as TCP reflection attacks and DNS reflection attacks with the highest probability of attack traffic.
How flat can you get? A model comparison perspective on the curvature of the Universe

The question of determining the spatial geometry of the Universe is of greater relevance than ever, as precision cosmology promises to verify inflationary predictions about the curvature of the Universe. We revisit the question of what can be learnt about the spatial geometry of the Universe from the perspective of a three-way Bayesian model comparison. By considering two classes of phenomenological priors for the curvature parameter, we show that, given the current data, the probability that the Universe is spatially infinite lies between 67 and 98 per cent, depending on the choice of priors. For the strongest prior choice, we find odds of the order of 50:1 (200:1 ) in favour of a flat Universe when compared with a closed (open) model. We also report a robust, prior-independent lower limit to the number of Hubble spheres in the Universe, N U ≥ 5 (at 99 per cent confidence). We forecast the accuracy with which future cosmic microwave background (CMB) and baryonic acoustic oscillation (BAO) observations will be able to constrain curvature, finding that a cosmic variance-limited CMB experiment together with an Square Kilometer Array (SKA)-like BAO observation will constrain curvature independently of the equation of state of dark energy with a precision of about σ ∼ 4.5 x 10 ―4 . We demonstrate that the risk of 'model confusion' (i.e. wrongly favouring a flat Universe in the presence of curvature) is much larger than might be assumed from parameter error forecasts for future probes. We argue that a 5σ detection threshold guarantees a confusion- and ambiguity-free model selection. Together with inflationary arguments, this implies that the geometry of the Universe is not knowable if the value of the curvature parameter is below |Ω κ | ∼ 10- 4 . This bound is one order of magnitude larger than what one would naively expect from the size of curvature perturbations, ∼10 ―5 .
Explicit Substitutions for Linear Logical Frameworks: Preliminary Results

We present the al ulus xdLLF and experiment with aspe ts of its meta-theory. xdLLF integrates linear expli it substitutions in de Bruijn notation into the simply-typed fragment of the linear logi al framework LLF. After observing that the expe ted -rules invalidate subje t redu tion, we devise a spe i ation of -normalization inspired by the big-step semanti s of programming languages, and prove it orre t.
Sensing Urban Land Use with Twitter Activity

Individuals generate vast amounts of geolocalized content through the use of mobile social media applications. In this context, Twitter has become an important sensor of the interactions between individuals and their environment. Building on this idea, the authors propose the use of geolocated tweets as a complementary source of information for urban planning applications, focusing on the characterization of land use. The authors’ proposed technique automatically determines land uses in urban areas by clustering geographical regions with similar tweeting activity patterns. Three case studies are presented and validated for Manhattan, London and Madrid using Twitter activity and land use information provided by the city planning departments. Results indicate that geolocated tweets can be used as a powerful data source for urban planning applications.
Exploring Supernumeraries - A New Marker for Screening of B-Chromosomes Presence in the Yellow Necked Mouse Apodemus flavicollis

Since the density of simple sequence repeats (SSRs) may vary between different chromosomes of the same species in eukaryotic genomes, we screened SSRs of the whole genome of the yellow necked mouse, Apodemus flavicollis, in order to reveal SSR profiles specific for animals carrying B chromosomes. We found that the 2200 bp band was amplified by primer (CAG)4AC to a highly increased level in samples with B chromosomes. This quantitative difference (B-marker) between animals with (+B) and without (0B) B chromosomes was used to screen 20 populations (387 animals). The presence/absence of Bs was confirmed in 96.5% of 342 non mosaic individuals, which recommends this method for noninvasive B-presence detection. A group of 45 animals with mosaic and micro B (μB) karyotypes was considered separately and showed 55.6% of overall congruence between karyotyping and molecular screening results. Relative quantification by qPCR of two different targeted sequences from B-marker indicated that these B-specific fragments are multiplied on B chromosomes. It also confirms our assumption that different types of Bs with variable molecular composition may exist in the same individual and between individuals of this species. Our results substantiate the origin of Bs from the standard chromosomal complement. The B-marker showed 98% sequence identity with the serine/threonine protein kinase VRK1 gene, similarly to findings reported for Bs from phylogenetically highly distant mammalian species. Evolutionarily conserved protein-coding genes found in Bs, including this one in A. flavicollis, could suggest a common evolutionary pathway.
Tauberian theorems for Cesàro summability of nth sequences

Tauberian theorem provides a criterion for the convergence of non convergent (summable) sequences. In this paper, we established a Tauberian theorem for nth real sequences via Cesàro summability by using de la Vallée Poussin mean and slow oscillation. The discussion and findings are capable to unify several useful concepts in the literature, and should also provide nontrivial extension of several results. Some examples are incorporated in support of our definitions and results. The findings are further expected to be helpful in designing and study several other interesting problems in summability theory and applications.
The Complexity of Tracking a Stopping Time

We present a generalization of the well-known Bayesian change-point detection problem. Specifically, let {(X<sub>i</sub>,Y<sub>i</sub>)}<sub>iges1</sub> be a sequence of pairs of random variables, and let S be a stopping time with respect to {X<sub>i</sub>}<sub>iges1</sub>. We assume that the (X<sub>i</sub>, Y<sub>i</sub>)'s take values in the same finite alphabet X times Y. For a fixed kappa ges 1, we consider the problem of finding a stopping time T < kappa with respect to {Y<sub>i</sub>}<sub>iges1</sub> that optimally tracks S, in the sense that T minimizes the average reaction time E(T - S)<sup>+</sup> , while it keeps the false-alarm probability P(T < S) below a given threshold alpha isin [0,1]. In previous work, we presented an algorithm that computes the optimal expected reaction times for all alpha isin [0,1] such that alpha ges P(S > kappa), and constructs the associated optimal stopping times T. In this paper, we provide a sufficient condition on {(X<sub>i</sub>,Y<sub>i</sub>)}<sub>iges1</sub> and S under which the algorithm running time is polynomial in kappa, and we illustrate this condition with two examples: a Bayesian change-point problem and a pure tracking stopping time problem.
Constitutively Active CCR5 Chemokine Receptors Differ in Mediating HIV Envelope-dependent Fusion

The CCR5 chemokine receptor is a rhodopsin-like G protein-coupled receptor that mediates the effects of pro-inflammatory β-chemokines. CCR5 is also the major co-receptor for entry of human immunodeficiency virus (HIV) into human cells. G protein-coupled receptors exist in ensembles of active and inactive conformations. Active receptor conformations can be stabilized by mutations. Although binding of the HIV envelope protein to CCR5 stimulates cellular signaling, the CCR5 conformation that induces fusion of the viral membrane with cellular membranes is not known. We mutated conserved amino acids to generate constitutively active CCR5 receptors, which are stabilized in active conformations, and tested the ability of constitutively active CCR5 receptors to mediate HIV envelope-directed membrane fusion. Mutation of the Asp3.49(125) and Arg6.32(225) residues of CCR5 did not cause constitutive activity, but Lys or Pro substitutions for Thr2.56(82), in the TxP motif, caused high basal inositol phosphate signaling. Signaling did not increase in response to MIP-1β, suggesting that the Thr2.56(82) mutants were fully stabilized in active conformations. The Thr2.56(82)Lys mutation severely decreased cell surface CCR5 expression. Combining the Thr2.56(82)Lys mutation with an Arg6.32(225)Gln mutation partially reversed the decrease in expression. Mutants with Thr2.56(82)Lys substitutions were poor mediators of HIV envelope-directed membrane fusion, but mutants with the Thr2.65(82)Pro substitution exhibited full co-receptor function. Our results suggest that the Thr2.65(82)Lys and Thr2.65(82)Pro mutations stabilize distinct constitutively active CCR5 conformations. Lys in position 2.65(82) stabilizes activated receptor conformations that appear to be constitutively internalized and do not induce envelope-dependent membrane fusion, whereas Pro stabilizes activated conformations that are not constitutively internalized and fully mediate envelope-directed membrane fusion.
Drag on a Satellite Moving across a Spherical Galaxy: Tidal and Frictional Forces in Short-lived Encounters

The drag force on a satellite of mass M moving with speed V in the gravitational field of a spherically symmetric background of stars is computed. During the encounter, the stars are subject to a time-dependent force that alters their equilibrium. The resulting distortion in the stellar density field acts back to produce a force FΔ that decelerates the satellite. This force is computed using a perturbative technique known as linear response theory. In this paper, we extend the formalism of linear response to derive the correct expression for the back-reaction force FΔ that applies when the stellar system is described by an equilibrium one-particle distribution function. FΔ is expressed in terms of a suitable correlation function that couples the satellite dynamics to the unperturbed dynamics of the stars. At time t, the force depends upon the whole history of the composite system. In the formalism, we account for the shift of the stellar center of mass resulting from linear momentum conservation. The self-gravity of the response is neglected since it contributes to a higher order in the perturbation. Linear response theory applies also to the case of a satellite orbiting outside the spherical galaxy. The case of a satellite moving on a straight line, at high speed relative to the stellar dispersion velocity, is explored. We find that the satellite during its passage raises (1) global tides in the stellar distribution and (2) a wake, i.e., an overdense region behind its trail. If the satellite motion is external to the galaxy, it suffers a dissipative force that is not exclusively acting along V but acquires a component along R, the position vector relative to the center of the spherical galaxy. We derive the analytical expression of the force in the impulse approximation. In penetrating short-lived encounters, the satellite moves across the stellar distribution and the transient wake excited in the density field is responsible for most of the deceleration. We find that dynamical friction arises from a memory effect involving only those stars perturbed along the path. The force can be written in terms of an effective Coulomb logarithm that now depends upon time. The value of ln Λ is computed for two simple equilibrium density distributions; it is shown that the drag increases as the satellite approaches the denser regions of the stellar distribution and attains a maximum after pericentric passage. When the satellite crosses the edge of the galaxy, the force does not vanish since the galaxy keeps memory of the perturbation induced and declines on a time comparable to the dynamical time of the stellar system. In the case of a homogeneous cloud, we compute the total energy loss. In evaluating the contribution resulting from friction, we derive self-consistently the maximum impact parameter, which is found to be equal to the length traveled by the satellite within the system. Tides excited by the satellite in the galaxy reduce the value of the energy loss by friction; in close encounters, this value is decreased by a factor of ~1.5.
Significance of Infectious Agents in Colorectal Cancer Development

Colorectal cancer (CRC) is a major burden to healthcare systems worldwide accounting for approximately one million of new cancer cases worldwide. Even though, CRC mortality has decreased over the last 20 years, it remains the third most common cause of cancer-related mortality, accounting for approximately 600,000 deaths in 2008 worldwide. A multitude of risk factors have been linked to CRC, including hereditary factors, environmental factors and inflammatory syndromes affecting the gastrointestinal tract. Recently, various pathogens were added to the growing list of risk factors for a number of common epithelial cancers, but despite the multitude of correlative studies, only suggestions remain about the possible relationship between selected viruses and bacteria of interest and the CRC risk. United States military service members are exposed to various risk factors impacting the incidence of cancer development. These exposures are often different from that of many sectors of the civilian population. Thereby, cancer risk identification, screening and early detection are imperative for both the military health care beneficiaries and the population as a whole. In this review, we will focus on several pathogens and their potential roles in development of CRC, highlighting the clinical trials evaluating this correlation and provide our personal opinion about the importance of risk reduction, health promotion and disease prevention for military health care beneficiaries.
TRUNCATED QZ METHODS FOR LARGE SCALE GENERALIZED EIGENVALUE PROBLEMS

This paper presents three methods for the large scale generalized eigenvalue problem . These methods are developed within a subspace projection framework as a truncation and modification of the QZ- algorithm for dense problems, that is suitable for computing partial generalized Schur decompositions of the pair ( ). A generalized partial reduction to condensed form is developed by analogy with the Arnoldi process. Then truncated forward and backward QZ iterations are introduced to derive generalizations of the Implicitly Restarted Arnoldi Method and the Truncated RQ method for the large scale generalized eigenvalue problem. These two meth- ods require the accurate solution of linear systems at each step of the iteration. Relaxing these accuracy requirements forces us to introduce non-Krylov projection spaces that lead most naturally to block variants of the QZ iterations. A two-block method is developed that incorporates approximate Newton corrections at each iteration. An important feature is the potential to utilize matrix vector products for each access of the matrix pair ( ). Preliminary computational experience is presented to compare the three new methods.
On the Evaluation of Transactor-based Verification for Reusing TLM Assertions and Testbenches at RTL

Transaction level modeling (TLM) is becoming a usual practice for simplifying system-level design and architecture exploration. It allows the designers to focus on the functionality of the design, while abstracting away implementation details that will be added at lower abstraction levels. However, moving from transaction level to RTL requires redefining TLM test benches and assertions. Such a wasteful and error prone conversion can be avoided by adopting transactor-based verification (TBV). Many recent works adopt this strategy to propose verification methodologies that allow: (1) mixing TLM and RTL components; and (2) reusing TLM assertions and test benches at RTL. Even if practical advantages of such an approach are evident, there are no papers in the literature that evaluate the effectiveness of the TBV compared to a more traditional RTL verification strategy. This paper is intended to fill in the gap. It theoretically compares the quality of the TBV towards the rewriting of assertions and test benches at RTL with respect to both fault coverage and assertion coverage
Single Trial P 300 Recognition in a Virtual

Virtual reality (VR) provides immersive and controllable experimental environments. It expands the bounds of possible evoked potential (EP) experiments by providing complex, dynamic environments in order to study cognition without sacriicing environmental control. The addition of quick, on-line analysis enables feedback to subjects, making the system we present ideal for safe Brain Computer Interface (BCI) research. In this context, we describe an experiment to recognize the existence of P300 EP epochs at red stoplights and the absence of this signal at yellow stoplights in a virtual driving environment. In order to determine the plausibility of single trial on-line P300 epoch analysis in the artifact ridden driving environment, we have compared the use of Independent Component Analysis (ICA), a Kalman lter, a robust Kalman lter, and correlation with the stoplight averages for recognition ability oo-line. We report that while all methods perform better than correlation , the robust Kalman lter gives the highest recognition accuracy and discuss future work in this context.
Stochastic Compounding and Uncertain Valuation December 30 , 2013

Exploring long-term implications of valuation leads us to recover and use a distorted probability measure that reflects the long-term implications for risk pricing. This measure is typically distinct from the physical and the risk neutral measures that are well known in mathematical finance. We apply a generalized version of Perron-Frobenius theory to construct this probability measure and present several applications. We employ Perron-Frobenius methods to i) explore the observational implications of risk adjustments and investor beliefs as reflected in asset market data; ii) catalog alternative forms of misspecification of parametric valuation models; and iii) characterize how long-term components of growth-rate risk impact investor preferences implied by Kreps-Porteus style utility recursions.
On cost matrices with two and three distinct values of Hamiltonian paths and cycles

A polynomial time testable characterization of cost matrices associated with a complete digraph on $n$ nodes such that all the Hamiltonian cycles (tours) have the same cost is well known. Tarasov [U.S.S.R. Comput. Maths. Math. Phys., 21 (1981), pp. 167-174. ] obtained a characterization of cost matrices where tour costs take two distinct values. We provide a simple alternative characterization of such cost matrices, which can be tested in $O(n^2)$ time. We also provide analogous results where tours are replaced by Hamiltonian paths. When the cost matrix is skew-symmetric, we provide polynomial time testable characterizations such that the tour costs take three distinct values. Corresponding results for the case of Hamiltonian paths are also given. Using these results, special instances of the asymmetric traveling salesman problem (ATSP) are identified that are solvable in polynomial time and that have improved constant factor approximation schemes. In particular, we observe that the 3/2 performance guarantee of the Christofides algorithm extends to all metric Hamiltonian symmetric matrices. Further, we identify special classes of ATSP for which polynomial $\epsilon$-approximation algorithms are available for $\epsilon \in \{3/2, 4/3, 4\tau, \frac{3\tau^2}{2}, \frac{4+\delta}{3}\}$, where $\tau > 1/2$ and $\delta \geq 0$ are constants.
Work in Progress: Assessing Engineering Students' Motivation and Learning Strategies - A Psychometric Analysis of the Motivated Strategies for Learning Questionnaire

This work in progress seeks to examine the psychometric analysis of the motivated strategies for learning questionnaire (MSLQ) for assessing engineering students’ motivation and learning strategies. Although there are many standardized questionnaires used to assess student motivation to learn, the MSLQ is one of the more widely used in general education research and has been reported to be reliable and valid. However, it has rarely been used in engineering education. The entire instrument comprises 81 items assessing motivation and learning strategies related constructs, with the motivation and learning strategies comprising six and nines sub-scales respectively. Constructs on the instrument are assessed on a 7-point Likert scale and scores are determined by obtaining participants mean score for items on each sub-scales. Confirmatory factor models were used to examine the performance of the MSLQ scales with the engineering student data. Preliminary findings show that the model fit was good to excellent for each sub-scale
Semi-automated Semantic Annotation of Learning Resources by Identifying Layout Features

It is now widely accepted that any kind of digital content must be somehow semantically annotated to be intelligently used by computer programs. Annotations can be metadata, descriptions, etc. When dealing with learning, most systems require the author to manually annotate resources so that the system can deploy a navigation strategy, an adaptive behavior etc. However this task is very problematic, and often reveals to be an overwhelming enterprise. In this paper we propose a methodology, based on the reuse of existing pedagogical documents to achieve a semi-automated extraction of semantic annotations by identifying semantic information contained in the layout. We are applying this methodology in the design of a Web Based Learning System.