pinecone/core-2020-05-10-deduplication huggingface dataset:
Stronger difficulty notions for client puzzles and denial-of-service-resistant protocols

Client puzzles are meant to act as a defense against denial of service (DoS) attacks by requiring a client to solve some moderately hard problem before being granted access to a resource.  However, recent client puzzle difficulty definitions (Stebila and Ustaoglu, 2009; Chen et al., 2009) do not ensure that solving n puzzles is n times harder than solving one puzzle.  Motivated by examples of puzzles where this is the case, we present stronger definitions of difficulty for client puzzles that are meaningful in the context of adversaries with more computational power than required to solve a single puzzle.\ud
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A protocol using strong client puzzles may still not be secure against DoS attacks if the puzzles are not used in a secure manner.  We describe a security model for analyzing the DoS resistance of any protocol in the context of client puzzles and give a generic technique for combining any protocol with a strong client puzzle to obtain a DoS-resistant protocol
SessionShield: Lightweight protection against session hijacking

The class of Cross-site Scripting (XSS) vulnerabilities is the most prevalent security problem in the field of Web applications. One of the main attack vectors used in connection with XSS is session hijacking via session identifier theft. While session hijacking is a client-side attack, the actual vulnerability resides on the server-side and, thus, has to be handled by the website's operator. In consequence, if the operator fails to address XSS, the application's users are defenseless against session hijacking attacks.

In this paper we present SessionShield, a lightweight client-side protection mechanism against session hijacking that allows users to protect themselves even if a vulnerable website's operator neglects to mitigate existing XSS problems. SessionShield is based on the observation that session identifier values are not used by legitimate
client-side scripts and, thus, need not to be available to the scripting languages running in the browser. Our system requires no training period and imposes negligible overhead to the browser, therefore, making it ideal for desktop and mobile systems.status: publishe
An Instruction to Accelerate Software Caches

In this paper we propose an instruction to accelerate software caches. While DMAs are very efficient for predictable data sets that can be fetched before they are needed, they introduce a large latency overhead for computations with unpredictable access behavior. Software caches are advantageous when the data set is not predictable but exhibits locality. However, software caches also incur a large overhead. Because the main overhead is in the access function, we propose an instruction that replaces the look-up function of the software cache. This instruction is evaluated using the Multidimensional Software Cache and two multimedia kernels, GLCM and H.264 Motion Compensation. The results show that the proposed instruction accelerates the software cache access time by a factor of 2.6. This improvement translates to a 2.1 speedup for GLCM and 1.28 for MC, when compared with the IBM software cache
Audio Cartography: Visual Encoding of Acoustic Parameters

Our sonic environment is the matter of subject in multiple domains which developed individual means of its description. As a result, it lacks an established visual language through which knowledge can be connected and insights shared. We provide a visual communication framework for the systematic and coherent documentation of sound in large-scale environments. This consists of visual encodings and mappings of acoustic parameters into distinct graphic variables that present plausible solutions for the visualization of sound. These candidate encodings are assembled into an application-independent, multifunctional, and extensible design guide. We apply the guidelines and show example maps that acts as a basis for the exploration of audio cartography
Resistive Random Access Memories (RRAMs) Based on Metal Nanoparticles

It is demonstrated that planar structures based on silver nanoparticleshosted in a polymer matrix show reliable and reproducible switching properties attractive for non-volatile memory applications. These systems can be programmed between a low conductance (off-state) and high conductance (on-state) with an on/off ratio of 3 orders of magnitude, large retention times and good cycle endurance. The planar structure design offers a series of advantages discussed in this contribution, which make it an ideal tool to elucidate the resistive switching phenomena
Worst case efficient single and multiple string matching in the Word-RAM
  model

In this paper, we explore worst-case solutions for the problems of single and
multiple matching on strings in the word RAM model with word length w. In the
first problem, we have to build a data structure based on a pattern p of length
m over an alphabet of size sigma such that we can answer to the following
query: given a text T of length n, where each character is encoded using
log(sigma) bits return the positions of all the occurrences of p in T (in the
following we refer by occ to the number of reported occurrences). For the
multi-pattern matching problem we have a set S of d patterns of total length m
and a query on a text T consists in finding all positions of all occurrences in
T of the patterns in S. As each character of the text is encoded using log
sigma bits and we can read w bits in constant time in the RAM model, we assume
that we can read up to (w/log sigma) consecutive characters of the text in one
time step. This implies that the fastest possible query time for both problems
is O((n(log sigma/w)+occ). In this paper we present several different results
for both problems which come close to that best possible query time. We first
present two different linear space data structures for the first and second
problem: the first one answers to single pattern matching queries in time
O(n(1/m+log sigma/w)+occ) while the second one answers to multiple pattern
matching queries to O(n((log d+log y+log log d)/y+log sigma/w)+occ) where y is
the length of the shortest pattern in the case of multiple pattern-matching. We
then show how a simple application of the four russian technique permits to get
data structures with query times independent of the length of the shortest
pattern (the length of the only pattern in case of single string matching) at
the expense of using more space.Comment: Full version of an extended abstract presented at IWOCA 2010
  conferenc
Single parameter FPT-algorithms for non-trivial games

We know that k-Uniform Nash is W[2]-Complete when we  consider imitation symmetric win-lose games (with k as the parameter)  even when we have two players. However, this paper provides positive  results regarding Nash equilibria. We show that consideration of sparse  games or limitations of the support result in  fixed-parameter algorithms  with respect to one parameter only for the k-Uniform Nash problem.  That is, we show that a sample uniform Nash equilibrium in r-sparse  imitation symmetric win-lose games is not as hard because it can be  found in FPT time (i.e polynomial in the size of the game, but maybe  exponential in r). Moreover, we show that, although NP-Complete, the  problem of Best Nash Equilibrium is also  x-parameter tractable.Griffith Sciences, School of Information and Communication TechnologyFull Tex
Computing role assignments of proper interval graphs in polynomial time.

A homomorphism from a graph G to a graph R is locally surjective if its restriction to the neighborhood of each vertex of G is surjective. Such a homomorphism is also called an R-role assignment of G. Role assignments have applications in distributed computing, social network theory, and topological graph theory. The Role Assignment problem has as input a pair of graphs (G,R) and asks whether G has an R-role assignment. This problem is NP-complete already on input pairs (G,R) where R is a path on three vertices. So far, the only known non-trivial tractable case consists of input pairs (G,R) where G is a tree. We present a polynomial time algorithm that solves Role Assignment on all input pairs (G,R) where G is a proper interval graph. Thus we identify the first graph class other than trees on which the problem is tractable. As a complementary result, we show that the problem is Graph Isomorphism-hard on chordal graphs, a superclass of proper interval graphs and trees
On the maximal sum of exponents of runs in a string

A run is an inclusion maximal occurrence in a string (as a subinterval) of a
repetition $v$ with a period $p$ such that $2p \le |v|$. The exponent of a run
is defined as $|v|/p$ and is $\ge 2$. We show new bounds on the maximal sum of
exponents of runs in a string of length $n$. Our upper bound of $4.1n$ is
better than the best previously known proven bound of $5.6n$ by Crochemore &
Ilie (2008). The lower bound of $2.035n$, obtained using a family of binary
words, contradicts the conjecture of Kolpakov & Kucherov (1999) that the
maximal sum of exponents of runs in a string of length $n$ is smaller than $2n$Comment: 7 pages, 1 figur
Efficient chaining of seeds in ordered trees

We consider here the problem of chaining seeds in ordered trees. Seeds are
mappings between two trees Q and T and a chain is a subset of non overlapping
seeds that is consistent with respect to postfix order and ancestrality. This
problem is a natural extension of a similar problem for sequences, and has
applications in computational biology, such as mining a database of RNA
secondary structures. For the chaining problem with a set of m constant size
seeds, we describe an algorithm with complexity O(m2 log(m)) in time and O(m2)
in space
Chains-into-Bins Processes

The study of {\em balls-into-bins processes} or {\em occupancy problems} has
a long history. These processes can be used to translate realistic problems
into mathematical ones in a natural way. In general, the goal of a
balls-into-bins process is to allocate a set of independent objects (tasks,
jobs, balls) to a set of resources (servers, bins, urns) and, thereby, to
minimize the maximum load. In this paper, we analyze the maximum load for the
{\em chains-into-bins} problem, which is defined as follows. There are $n$
bins, and $m$ objects to be allocated. Each object consists of balls connected
into a chain of length $\ell$, so that there are $m \ell$ balls in total. We
assume the chains cannot be broken, and that the balls in one chain have to be
allocated to $\ell$ consecutive bins. We allow each chain $d$ independent and
uniformly random bin choices for its starting position. The chain is allocated
using the rule that the maximum load of any bin receiving a ball of that chain
is minimized. We show that, for $d \ge 2$ and $m\cdot\ell=O(n)$, the maximum
load is $((\ln \ln m)/\ln d) +O(1)$ with probability $1-\tilde O(1/m^{d-1})$
Shortest paths between shortest paths and independent sets

We study problems of reconfiguration of shortest paths in graphs. We prove
that the shortest reconfiguration sequence can be exponential in the size of
the graph and that it is NP-hard to compute the shortest reconfiguration
sequence even when we know that the sequence has polynomial length. Moreover,
we also study reconfiguration of independent sets in three different models and
analyze relationships between these models, observing that shortest path
reconfiguration is a special case of independent set reconfiguration in perfect
graphs, under any of the three models. Finally, we give polynomial results for
restricted classes of graphs (even-hole-free and $P_4$-free graphs)
A practical approach to portscan detection in very high-speed links

Port scans are continuously used by both worms and human attackers to probe for vulnerabilities in Internet facing systems. In this paper, we present a new method to efficiently detect TCP port scans in\ud
very high-speed links. The main idea behind our approach is to early discard those handshake packets that are not strictly needed to reliably detect port scans. We show that with just a couple of Bloom filters to track active servers and TCP handshakes we can easily discard about 85% of\ud
all handshake packets with negligible loss in accuracy. This significantly reduces both the memory requirements and CPU cost per packet. We evaluated our algorithm using packet traces and live traffic from 1 and\ud
10 GigE academic networks. Our results show that our method requires less than 1 MB to accurately monitor a 10 Gb/s link, which perfectly fits in the cache memory of nowadays’ general-purpose processors.Peer ReviewedPostprint (published version
Reconstructing mass-conserved water surfaces using shape from shading and optical flow

This paper introduces a method for reconstructing water from real video footage. Using a single input video, the proposed method produces a more informative reconstruction from a wider range of possible scenes than the current state of the art. The key is the combination of vision algorithms and physics laws. Shape from shading is used to capture the change of the water's surface, from which a vertical velocity gradient field is calculated. Such a gradient field is used to constrain the tracking of horizontal velocities by minimizing an energy function as a weighted combination of mass-conservation and intensity-conservation. Hence the final reconstruction contains a dense velocity field that is incompressible in 3D. The proposed method is efficient and performs consistently well across water of different types
Extending AMCW lidar depth-of-field using a coded aperture

By augmenting a high resolution full-field Amplitude Modulated Continuous Wave lidar system with a coded aperture, we show that depth-of-field can be extended using explicit, albeit blurred, range data to determine PSF scale. Because complex domain range-images contain explicit range information, the aperture design is unconstrained by the necessity for range determination by depth-from-defocus. The coded aperture design is shown to improve restoration quality over a circular aperture. A proof-of-concept algorithm using dynamic PSF determination and spatially variant Landweber iterations is developed and using an empirically sampled point spread function is shown to work in cases without serious multipath interference or high phase complexity
Affordance mining: Forming perception through action

This work employs data mining algorithms to discover visual entities that are strongly associated to autonomously discovered modes of action, in an embodied agent. Mappings are learnt from these perceptual entities, onto the agents action space. In general, low dimensional action spaces are better suited to unsupervised learning than high dimensional percept spaces, allowing for structure to be discovered in the action space, and used to organise the perceptual space. Local feature configurations that are strongly associated to a particular ‘type’ of action (and not all other action types) are considered likely to be relevant in eliciting that action type. By learning mappings from these relevant features onto the action space, the system is able to respond in real time to novel visual stimuli. The proposed approach is demonstrated on an autonomous navigation task, and the system is shown to identify the relevant visual entities to the task and to generate appropriate responses
A temporal latent topic model for facial expression recognition

Posters: no. 128LNCS v. 6495 is conference proceedings of the  10th Asian Conference on Computer Vision, Queens, ACCVIn this paper we extend the latent Dirichlet allocation (LDA) topic model to model facial expression dynamics. Our topic model integrates the temporal information of image sequences through redefining topic generation probability without involving new latent variables or increasing inference difficulties. A collapsed Gibbs sampler is derived for batch learning with labeled training dataset and an efficient learning method for testing data is also discussed. We describe the resulting temporal latent topic model (TLTM) in detail and show how it can be applied to facial expression recognition. Experiments on CMU expression database illustrate that the proposed TLTM is very efficient in facial expression recognition. © 2011 Springer-Verlag Berlin Heidelberg.postprintThe 10th Asian Conference on Computer Vision (ACCV 2010), Queenstown, New Zealand, 8-12 November 2010. In Lecture Notes in Computer Science, 2010, v. 6495, p. 51-6
Specular surface recovery from reflections of a planar pattern undergoing an unknown pure translation

LNCS v. 6493 entitled: Computer Vision – ACCV 2010: 10th Asian Conference on Computer Vision, Queenstown, New Zealand, November 8-12, 2010, Revised Selected Papers, Part 2This paper addresses the problem of specular surface recovery, and proposes a novel solution based on observing the reflections of a translating planar pattern. Previous works have demonstrated that a specular surface can be recovered from the reflections of two calibrated planar patterns. In this paper, however, only one reference planar pattern is assumed to have been calibrated against a fixed camera observing the specular surface. Instead of introducing and calibrating a second pattern, the reference pattern is allowed to undergo an unknown pure translation, and a closed form solution is derived for recovering such a motion. Unlike previous methods which estimate the shape by directly triangulating the visual rays and reflection rays, a novel method based on computing the projections of the visual rays on the translating pattern is introduced. This produces a depth range for each pixel which also provides a measure of the accuracy of the estimation. The proposed approach enables a simple auto-calibration of the translating pattern, and data redundancy resulting from the translating pattern can improve both the robustness and accuracy of the shape estimation. Experimental results on both synthetic and real data are presented to demonstrate the effectiveness of the proposed approach. © 2011 Springer-Verlag Berlin Heidelberg.postprintThe 10th Asian Conference on Computer Vision, Queenstown, New Zealand, 8-12 November 2010. In Lecture Notes in Computer Science, 2010, v. 6493, p. 137-14
A theoretical and numerical study of a phase field higher-order active contour model of directed networks.

We address the problem of quasi-automatic extraction of directed networks, which have characteristic geometric features, from images. To include the necessary prior knowledge about these geometric features, we use a phase field higher-order active contour model of directed networks. The model has a large number of unphysical parameters (weights of energy terms), and can favour different geometric structures for different parameter values. To overcome this problem, we perform a stability analysis of a long, straight bar in order to find parameter ranges that favour networks. The resulting constraints necessary to produce stable networks eliminate some parameters, replace others by physical parameters such as network branch width, and place lower and upper bounds on the values of the rest. We validate the theoretical analysis via numerical experiments, and then apply the model to the problem of hydrographic network extraction from multi-spectral VHR satellite images
Hemispherical confocal imaging using turtleback reflector

We propose a new imaging method called hemispherical confocal imaging to clearly visualize a particular depth in a 3-D scene. The key optical component is a turtleback reflector which is a specially designed polyhedral mirror. By combining the turtleback reflector with a coaxial pair of a camera and a projector, many virtual cameras and projectors are produced on a hemisphere with uniform density to synthesize a hemispherical aperture. In such an optical device, high frequency illumination can be focused at a particular depth in the scene to visualize only the depth with descattering. Then, the observed views are factorized into masking, attenuation, and texture terms to enhance visualization when obstacles are present. Experiments using a prototype system show that only the particular depth is effectively illuminated and hazes by scattering and attenuation can be recovered even when obstacles exist.Microsoft ResearchJapan Society for the Promotion of Science (Grants-in-Aid For Scientific Research 21680017)Japan Society for the Promotion of Science (Grants-in-Aid For Scientific Research 21650038
On-line multi-threaded processing of web user-clicks on multi-core processors.

Medical imaging has become an absolutely essential diagnostic tool for clinical practices; at present, pathologies can be detected with an earliness never before known. Its use has not only been relegated to the field of radiology but also, increasingly, to computer-based imaging processes prior to surgery. Motion analysis, in particular, plays an important role in analyzing activities or behaviors of live objects in medicine. This short paper presents several low-cost hardware implementation approaches for the new generation of tablets and/or smartphones for estimating motion compensation and segmentation in medical images. These systems have been optimized for breast cancer diagnosis using magnetic resonance imaging technology with several advantages over traditional X-ray mammography, for example, obtaining patient information during a short period. This paper also addresses the challenge of offering a medical tool that runs on widespread portable devices, both on tablets and/or smartphones to aid in patient diagnostics
MIRAGE: a management tool for the analysis and deployment of network security policies

International audienceWe present the core functionality of MIRAGE, a management tool for the analysis and deployment of configuration policies over network security components, such as firewalls, intrusion detection systems, and VPN routers.We review the two main functionalities embedded in our current prototype: (1) a bottom-up analysis of already deployed network security configurations and (2) a top-down refinement of global policies into network security component configurations. In both cases, MIRAGE provides intra-component analysis to detect inconsistencies in single component deployments; and inter-component analysis, to detect multicomponent deployments which are not consistent. MIRAGE also manages the description of the security architecture topology, to guarantee the proper execution of all the processes
L–PEP: a logic to reason about privacy–enhancing cryptography protocols

Proceedings of: 5th International Workshop, DPM 2010 and 3rd International Workshop, SETOP 2010, Athens, Greece, September 23, 2010.In recent years, many cryptography protocols have been designed, for many different scenarios, with the purpose of preserving security of communications as well as privacy and anonymity of participant entities. In general, every proposed solution has possed a real challenge to the existing formal methods of protocol analysis and verification. The main goal of this work is the proposal of a logic to reason about privacy-enhancing monotonic and non-monotonic cryptography protocols. The new logic will be called L-PEP and it extends the existing Rubin's logic of beliefs.Publicad