OpenRaiser/Intern-Atlas huggingface dataset:
Processing stationary noise: model and parameter selection in variational methods
Venue: arXiv cs.CV 2013
Year: 2013

Additive or multiplicative stationary noise recently became an important issue in applied fields such as microscopy or satellite imaging. Relatively few works address the design of dedicated denoising methods compared to the usual white noise setting. We recently proposed a variational algorithm to tackle this issue. In this paper, we analyze this problem from a statistical point of view and provide deterministic properties of the solutions of the associated variational problems. In the first part of this work, we demonstrate that in many practical problems, the noise can be assimilated to a colored Gaussian noise. We provide a quantitative measure of the distance between a stationary process and the corresponding Gaussian process. In the second part, we focus on the Gaussian setting and analyze denoising methods which consist of minimizing the sum of a total variation term and an $l^2$ data fidelity term. While the constrained formulation of this problem allows to easily tune the parameters, the Lagrangian formulation can be solved more efficiently since the problem is strongly convex. Our second contribution consists in providing analytical values of the regularization parameter in order to approximately satisfy Morozov's discrepancy principle.
A Design Methodology for Software Measurement Programs
Venue: arXiv cs.SE 2013
Year: 2013

Software measurement programs have emerged as compounds of several measurement activities that are pursued as part of a combined effort of several parties within a software organization, based on interests that the organization has regarding the assessment of the different elements that intervene in the development of software. This paper recognizes design of measurement programs as an essential activity that, up until now, has been studied extensively, however, only in what respects to the content of the programs. In addition, proper specification for this kind of programs, accounting for preciseness and unambiguity, to facilitate maintenance, evolution, and execution has not been thoroughly considered. A methodology for designing programs that embody these and some other desirable features is presented. The methodology is built in solid ground. From software measurement literature, a goal-oriented approach is considered for building the content of the program. On the other hand, a successful technique from software development as modularization is utilized to give coherent structure to the measurement program.
A Nested Partitioning Scheme for Parallel Heterogeneous Clusters
Venue: arXiv cs.DC 2013
Year: 2013

Modern supercomputers are increasingly requiring the presence of accelerators and co-processors. However, it has not been easy to achieve good performance on such heterogeneous clusters. The key challenge has been to ensure good load balance and that neither the CPU nor the accelerator is left idle. Traditional approaches have offloaded entire computations to the accelerator, resulting in an idle CPU, or have opted for task-level parallelism requiring large data transfers between the CPU and the accelerator. True work-parallelism has been hard as the Accelerators cannot directly communicate with other CPUs (besides the host) and Accelerators. In this work, we present a new nested partition scheme to overcome this problem. By partitioning the work assignment on a given node asymmetrically into boundary and interior work, and assigning the interior to the accelerator, we are able to achieve excellent efficiency while ensure proper utilization of both the CPU and Accelerator resources. The problem used for evaluating the new partition is an $hp$ discontinuous Galerkin spectral element method for a coupled elastic--acoustic wave propagation problem.
Characterizing traits of coordination
Venue: arXiv cs.PL 2013
Year: 2013

How can one recognize coordination languages and technologies? As this report shows, the common approach that contrasts coordination with computation is intellectually unsound: depending on the selected understanding of the word "computation", it either captures too many or too few programming languages. Instead, we argue for objective criteria that can be used to evaluate how well programming technologies offer coordination services. Of the various criteria commonly used in this community, we are able to isolate three that are strongly characterizing: black-box componentization, which we had identified previously, but also interface extensibility and customizability of run-time optimization goals. These criteria are well matched by Intel's Concurrent Collections and AstraKahn, and also by OpenCL, POSIX and VMWare ESX.
Power Efficiency for Device-to-Device Communications
Venue: arXiv cs.NI 2013
Year: 2013

The concept of device-to-Device (D2D) communication as an underlay coexistence with cellular networks gains many advantages of improving system performance. In this paper, we model such a two-layer heterogenous network based on stochastic geometry approach. We aim at minimizing the expected power consumption of the D2D layer while satisfying the outage performance of both D2D layer and cellular layer. We consider two kinds of power control schemes. The first one is referred as to independent power control where the transmit powers are statistically independent of the networks and all channel conditions. The second is named as dependent power control where the transmit power of each user is dependent on its own channel condition. A closed-form expression of optimal independent power control is derived, and we point out that the optimal power control for this case is fixed and not relevant to the randomness of the network. For the dependent power control case, we propose an efficient way to find the close-to-optimal solution for the power-efficiency optimization problem. Numerical results show that dependent power control scheme saves about half of power that the independent power control scheme demands.
Linear-Time FPT Algorithms via Network Flow
Venue: arXiv cs.DS 2013
Year: 2013

In the area of parameterized complexity, to cope with NP-Hard problems, we introduce a parameter k besides the input size n, and we aim to design algorithms (called FPT algorithms) that run in O(f(k)n^d) time for some function f(k) and constant d. Though FPT algorithms have been successfully designed for many problems, typically they are not sufficiently fast because of huge f(k) and d. In this paper, we give FPT algorithms with small f(k) and d for many important problems including Odd Cycle Transversal and Almost 2-SAT. More specifically, we can choose f(k) as a single exponential (4^k) and d as one, that is, linear in the input size. To the best of our knowledge, our algorithms achieve linear time complexity for the first time for these problems. To obtain our algorithms for these problems, we consider a large class of integer programs, called BIP2. Then we show that, in linear time, we can reduce BIP2 to Vertex Cover Above LP preserving the parameter k, and we can compute an optimal LP solution for Vertex Cover Above LP using network flow. Then, we perform an exhaustive search by fixing half-integral values in the optimal LP solution for Vertex Cover Above LP. A bottleneck here is that we need to recompute an LP optimal solution after branching. To address this issue, we exploit network flow to update the optimal LP solution in linear time.
ANANAS - A Framework For Analyzing Android Applications
Venue: arXiv cs.CR 2013
Year: 2013

Android is an open software platform for mobile devices with a large market share in the smartphone sector. The openness of the system as well as its wide adoption lead to an increasing amount of malware developed for this platform. ANANAS is an expandable and modular framework for analyzing Android applications. It takes care of common needs for dynamic malware analysis and provides an interface for the development of plugins. Adaptability and expandability have been main design goals during the development process. An abstraction layer for simple user interaction and phone event simulation is also part of the framework. It allows an analyst to script the required user simulation or phone events on demand or adjust the simulation to his needs. Six plugins have been developed for ANANAS. They represent well known techniques for malware analysis, such as system call hooking and network traffic analysis. The focus clearly lies on dynamic analysis, as five of the six plugins are dynamic analysis methods.
10 Inventions on improving keyboard efficiency: A TRIZ based analysis
Venue: arXiv cs.HC 2013
Year: 2013

A keyboard is the most important input device for a computer. With the development of technology a basic keyboard does not want to remain confined within the basic functionalities of a keyboard, rather it wants to go beyond. There are several inventions which attempt to improve the efficiency of a conventional keyboard. This article illustrates 10 inventions from US Patent database all of which have proposed very interesting methods for improving the efficiency of a computer keyboard. Some interesting inventions include, adding toolbar buttons on the keyboard, power saving method, keyboard-cooling mechanism, robust keyboard for public use, keyboard enhancement for children`s use. Each of these inventions have been analyzed from TRIZ perspective, in many cases formulating the Ideal Final Result, contradictions and highlighting the Inventive Principles used in the solution.
Distributed Computation of the Conditional PCRLB for Quantized Decentralized Particle Filters
Venue: arXiv cs.DC 2013
Year: 2013

The conditional posterior Cramer-Rao lower bound (PCRLB) is an effective sensor resource management criteria for large, geographically distributed sensor networks. Existing algorithms for distributed computation of the PCRLB (dPCRLB) are based on raw observations leading to significant communication overhead to the estimation mechanism. This letter derives distributed computational techniques for determining the conditional dPCRLB for quantized, decentralized sensor networks (CQ/dPCRLB). Analytical expressions for the CQ/dPCRLB are derived, which are particularly useful for particle filter-based estimators. The CQ/dPCRLB is compared for accuracy with its centralized counterpart through Monte-Carlo simulations.
Any Positive Feedback Rate Increases the Capacity of Strictly Less-Noisy Broadcast Channels
Venue: arXiv cs.IT 2013
Year: 2013

We propose two coding schemes for discrete memoryless broadcast channels (DMBCs) with rate-limited feedback from only one receiver. For any positive feedback rate and for the class of strictly less-noisy DMBCs, our schemes strictly improve over the no-feedback capacity region.
Sub-Dividing Genetic Method for Optimization Problems
Venue: arXiv cs.NE 2013
Year: 2013

Nowadays, optimization problem have more application in all major but they have problem in computation. Computation global point in continuous functions have high calculation and this became clearer in large space .In this paper, we proposed Sub- Dividing Genetic Method(SGM) that have less computation than other method for achieving global points . This method userotation mutation and crossover based sub-division method that sub diving method is used for minimize search space and rotation mutation with crossover is used for finding global optimal points. In experimental, SGM algorithm is implemented on De Jong function. The numerical examples show that SGM is performed more optimal than other methods such as Grefensstette, Random Value, and PNG.
An Evaluation of Caching Policies for Memento TimeMaps
Venue: arXiv cs.DL 2013
Year: 2013

As defined by the Memento Framework, TimeMaps are ma-chine-readable lists of time-specific copies -- called "mementos" -- of an archived original resource. In theory, as an archive acquires additional mementos over time, a TimeMap should be monotonically increasing. However, there are reasons why the number of mementos in a TimeMap would decrease, for example: archival redaction of some or all of the mementos, archival restructuring, and transient errors on the part of one or more archives. We study TimeMaps for 4,000 original resources over a three month period, note their change patterns, and develop a caching algorithm for TimeMaps suitable for a reverse proxy in front of a Memento aggregator. We show that TimeMap cardinality is constant or monotonically increasing for 80.2% of all TimeMap downloads observed in the observation period. The goal of the caching algorithm is to exploit the ideally monotonically increasing nature of TimeMaps and not cache responses with fewer mementos than the already cached TimeMap. This new caching algorithm uses conditional cache replacement and a Time To Live (TTL) value to ensure the user has access to the most complete TimeMap available. Based on our empirical data, a TTL of 15 days will minimize the number of mementos missed by users, and minimize the load on archives contributing to TimeMaps.
Is Bottom-Up Attention Useful for Scene Recognition?
Venue: arXiv cs.CV 2013
Year: 2013

The human visual system employs a selective attention mechanism to understand the visual world in an eficient manner. In this paper, we show how computational models of this mechanism can be exploited for the computer vision application of scene recognition. First, we consider saliency weighting and saliency pruning, and provide a comparison of the performance of different attention models in these approaches in terms of classification accuracy. Pruning can achieve a high degree of computational savings without significantly sacrificing classification accuracy. In saliency weighting, however, we found that classification performance does not improve. In addition, we present a new method to incorporate salient and non-salient regions for improved classification accuracy. We treat the salient and non-salient regions separately and combine them using Multiple Kernel Learning. We evaluate our approach using the UIUC sports dataset and find that with a small training size, our method improves upon the classification accuracy of the baseline bag of features approach.
Saliency-Guided Perceptual Grouping Using Motion Cues in Region-Based Artificial Visual Attention
Venue: arXiv cs.CV 2013
Year: 2013

Region-based artificial attention constitutes a framework for bio-inspired attentional processes on an intermediate abstraction level for the use in computer vision and mobile robotics. Segmentation algorithms produce regions of coherently colored pixels. These serve as proto-objects on which the attentional processes determine image portions of relevance. A single region---which not necessarily represents a full object---constitutes the focus of attention. For many post-attentional tasks, however, such as identifying or tracking objects, single segments are not sufficient. Here, we present a saliency-guided approach that groups regions that potentially belong to the same object based on proximity and similarity of motion. We compare our results to object selection by thresholding saliency maps and a further attention-guided strategy.
An Adaptive GMM Approach to Background Subtraction for Application in Real Time Surveillance
Venue: arXiv cs.CV 2013
Year: 2013

Efficient security management has become an important parameter in todays world. As the problem is growing, there is an urgent need for the introduction of advanced technology and equipment to improve the state-of art of surveillance. In this paper we propose a model for real time background subtraction using AGMM. The proposed model is robust and adaptable to dynamic background, fast illumination changes, repetitive motion. Also we have incorporated a method for detecting shadows using the Horpresert color model. The proposed model can be employed for monitoring areas where movement or entry is highly restricted. So on detection of any unexpected events in the scene an alarm can be triggered and hence we can achieve real time surveillance even in the absence of constant human monitoring.
Cooperative Energy Harvesting Networks with Spatially Random Users
Venue: arXiv cs.IT 2013
Year: 2013

This paper considers a cooperative network with multiple source-destination pairs and one energy harvesting relay. The outage probability experienced by users in this network is characterized by taking the spatial randomness of user locations into consideration. In addition, the cooperation among users is modeled as a canonical coalitional game and the grand coalition is shown to be stable in the addressed scenario. Simulation results are provided to demonstrate the accuracy of the developed analytical results.
A New Approach for Finding the Global Optimal Point Using Subdividing Labeling Method (SLM)
Venue: arXiv cs.NE 2013
Year: 2013

In most global optimization problems, finding global optimal point inthe multidimensional and great search space needs high computations. In this paper, we present a new approach to find global optimal point with the low computation and few steps using subdividing labeling method (SLM) which can also be used in the multi-dimensional and great search space. In this approach, in each step, crossing points will be labeled and complete label polytope search space of selected polytope will be subdivided after being selected. SLM algorithm finds the global point until h (subdivision function) turns into zero. SLM will be implemented on five applications and compared with the latest techniques such as random search, random search-walk and simulated annealing method. The results of the proposed method demonstrate that our new approach is faster and more reliable and presents an optimal time complexity O (logn).
Optimal Hierarchical Layouts for Cache-Oblivious Search Trees
Venue: arXiv cs.DS 2013
Year: 2013

This paper proposes a general framework for generating cache-oblivious layouts for binary search trees. A cache-oblivious layout attempts to minimize cache misses on any hierarchical memory, independent of the number of memory levels and attributes at each level such as cache size, line size, and replacement policy. Recursively partitioning a tree into contiguous subtrees and prescribing an ordering amongst the subtrees, Hierarchical Layouts generalize many commonly used layouts for trees such as in-order, pre-order and breadth-first. They also generalize the various flavors of the van Emde Boas layout, which have previously been used as cache-oblivious layouts. Hierarchical Layouts thus unify all previous attempts at deriving layouts for search trees. The paper then derives a new locality measure (the Weighted Edge Product) that mimics the probability of cache misses at multiple levels, and shows that layouts that reduce this measure perform better. We analyze the various degrees of freedom in the construction of Hierarchical Layouts, and investigate the relative effect of each of these decisions in the construction of cache-oblivious layouts. Optimizing the Weighted Edge Product for complete binary search trees, we introduce the MinWEP layout, and show that it outperforms previously used cache-oblivious layouts by almost 20%.
Online Communities: Visualization and Formalization
Venue: arXiv cs.SI 2013
Year: 2013

Online communities have increased in size and importance dramatically over the last decade. The fact that many communities are online means that it is possible to extract information about these communities and the connections between their members much more easily using software tools, despite their potentially very large size. The links between members of the community can be presented visually and often this can make patterns in the structure of sub-communities immediately obvious. The links and structures of layered communities can also be formalized to gain a better understanding of their modelling. This paper explores these links with some specific examples, including visualization of these relationships and a formalized model of communities using the Z notation. It also considers the development of such communities within the Community of Practice social science framework. Such approaches may be applicable for communities associated with cybersecurity and could be combined for a better understanding of their development.
A novel approach of solving the CNF-SAT problem
Venue: arXiv cs.AI 2013
Year: 2013

In this paper, we discussed CNF-SAT problem (NP-Complete problem) and analysis two solutions that can solve the problem, the PL-Resolution algorithm and the WalkSAT algorithm. PL-Resolution is a sound and complete algorithm that can be used to determine satisfiability and unsatisfiability with certainty. WalkSAT can determine satisfiability if it finds a model, but it cannot guarantee to find a model even there exists one. However, WalkSAT is much faster than PL-Resolution, which makes WalkSAT more practical; and we have analysis the performance between these two algorithms, and the performance of WalkSAT is acceptable if the problem is not so hard.
The wireless router based on the linux system
Venue: arXiv cs.NI 2013
Year: 2013

With the expansion of computer networks,the mobile terminal with wireless access capability experience a sharp increase in the number of wireless routers, especially low cost wireless routers are becoming very important network equipment. This paper designs a wireless router based on the ARM platform, the Linux system. First, there is a research and analysis on the working principle and implementation of Network Address Translation (NAT) technology. Then I study the IPTABLES components under the Linux system and use it when processing data packets which go into the chain and the table and finally using laptop with Ethernet card and the WIFI card to build the Linux operating system. Related routing forwarding rules are defined between the two cards and use IPTABLES to achieve a laptop as a wireless WIFI hotspot providing routing and network connections to other computer services. It proves this paper's design, and production feasibility. The paper also discusses the design and production method of the wireless router with ARM board feasibility.
Protecting Anti-virus Programs From Viral Attacks
Venue: arXiv cs.CR 2013
Year: 2013

During a fight between viruses and anti-viruses it is not always predictable that the anti-virus is going to win. There are many malicious viruses which target to attack and paralyze the anti-viruses. It is necessary for an anti-virus to detect and destroy the malware before its own files are detected and destroyed by the malware. The anti-virus may follow thorough testing and auditing procedures to fix all its bugs before releasing the software in the market. Besides the anti-virus may use all the obfuscation techniques like polymorphism that the viruses generally use to hide their codes. This article also shows how to use TRIZ Inventive Standards to solve the harmful effects of the viruses on the anti-virus.