OpenRaiser/Intern-Atlas huggingface dataset:
On the Generalized Hermite-Based Lattice Boltzmann Construction, Lattice Sets, Weights, Moments, Distribution Functions and High-Order Models
Venue: arXiv cs.CE 2013
Year: 2013

The influence of the use of the generalized Hermite polynomial on the Hermite-based lattice Boltzmann (LB) construction approach, lattice sets, the thermal weights, moments and the equilibrium distribution function (EDF) are addressed. A new moment system is proposed. The theoretical possibility to obtain a high-order Hermite-based LB model capable to exactly match some first hydrodynamic moments thermally 1) on-Cartesian lattice, 2) with thermal weights in the EDF, 3) whilst the highest possible hydrodynamic moments that are exactly matched are obtained with the shortest on-Cartesian lattice sets with some fixed real-valued temperatures, is also analyzed. Keywords: Lattice Boltzmann, fluid dynamics, kinetic theory, distribution function
h-approximation: History-Based Approximation of Possible World Semantics as ASP
Venue: arXiv cs.AI 2013
Year: 2013

We propose an approximation of the Possible Worlds Semantics (PWS) for action planning. A corresponding planning system is implemented by a transformation of the action specification to an Answer-Set Program. A novelty is support for postdiction wrt. (a) the plan existence problem in our framework can be solved in NP, as compared to $Σ_2^P$ for non-approximated PWS of Baral(2000); and (b) the planner generates optimal plans wrt. a minimal number of actions in $Δ_2^P$. We demo the planning system with standard problems, and illustrate its integration in a larger software framework for robot control in a smart home.
Comparing journals from different fields of Science and Social Science through a JCR Subject Categories Normalized Impact Factor
Venue: arXiv cs.DL 2013
Year: 2013

The journal Impact Factor (IF) is not comparable among fields of Science and Social Science because of systematic differences in publication and citation behaviour across disciplines. In this work, a decomposing of the field aggregate impact factor into five normally distributed variables is presented. Considering these factors, a Principal Component Analysis is employed to find the sources of the variance in the JCR subject categories of Science and Social Science. Although publication and citation behaviour differs largely across disciplines, principal components explain more than 78% of the total variance and the average number of references per paper is not the primary factor explaining the variance in impact factors across categories. The Categories Normalized Impact Factor (CNIF) based on the JCR subject category list is proposed and compared with the IF. This normalization is achieved by considering all the indexing categories of each journal. An empirical application, with one hundred journals in two or more subject categories of economics and business, shows that the gap between rankings is reduced around 32% in the journals analyzed. This gap is obtained as the maximum distance among the ranking percentiles from all categories where each journal is included.
Central indexes to the citation distribution: A complement to the h-index
Venue: arXiv cs.DL 2013
Year: 2013

The citation distribution of a researcher shows the impact of their production and determines the success of their scientific career. However, its application in scientific evaluation is difficult due to the bi-dimensional character of the distribution. Some bibliometric indexes that try to synthesize in a numerical value the principal characteristics of this distribution have been proposed recently. In contrast with other bibliometric measures, the biases that the distribution tails provoke, are reduced by the h-index. However, some limitations in the discrimination among researchers with different publication habits are presented in this index. This index penalizes selective researchers, distinguished by the large number of citations received, as compared to large producers. In this work, two original sets of indexes, the central area indexes and the central interval indexes, that complement the h-index to include the central shape of the citation distribution, are proposed and compared.
MinMax-Profiles: A Unifying View of Common Intervals, Nested Common Intervals and Conserved Intervals of K Permutations
Venue: arXiv cs.DS 2013
Year: 2013

Common intervals of K permutations over the same set of n elements were firstly investigated by T. Uno and M.Yagiura (Algorithmica, 26:290:309, 2000), who proposed an efficient algorithm to find common intervals when K=2. Several particular classes of intervals have been defined since then, e.g. conserved intervals and nested common intervals, with applications mainly in genome comparison. Each such class, including common intervals, led to the development of a specific algorithmic approach for K=2, and - except for nested common intervals - for its extension to an arbitrary K. In this paper, we propose a common and efficient algorithmic framework for finding different types of common intervals in a set P of K permutations, with arbitrary K. Our generic algorithm is based on a global representation of the information stored in P, called the MinMax-profile of P, and an efficient data structure, called an LR-stack, that we introduce here. We show that common intervals (and their subclasses of irreducible common intervals and same-sign common intervals), nested common intervals (and their subclass of maximal nested common intervals) as well as conserved intervals (and their subclass of irreducible conserved intervals) may be obtained by appropriately setting the parameters of our algorithm in each case. All the resulting algorithms run in O(Kn+N)-time and need O(n) additional space, where N is the number of solutions. The algorithms for nested common intervals and maximal nested common intervals are new for K>2, in the sense that no other algorithm has been given so far to solve the problem with the same complexity, or better. The other algorithms are as efficient as the best known algorithms.
Image Retrieval based on Bag-of-Words model
Venue: arXiv cs.IR 2013
Year: 2013

This article gives a survey for bag-of-words (BoW) or bag-of-features model in image retrieval system. In recent years, large-scale image retrieval shows significant potential in both industry applications and research problems. As local descriptors like SIFT demonstrate great discriminative power in solving vision problems like object recognition, image classification and annotation, more and more state-of-the-art large scale image retrieval systems are trying to rely on them. A common way to achieve this is first quantizing local descriptors into visual words, and then applying scalable textual indexing and retrieval schemes. We call this model as bag-of-words or bag-of-features model. The goal of this survey is to give an overview of this model and introduce different strategies when building the system based on this model.
Ball-Larus Path Profiling Across Multiple Loop iterations
Venue: arXiv cs.PL 2013
Year: 2013

Identifying the hottest paths in the control flow graph of a routine can direct optimizations to portions of the code where most resources are consumed. This powerful methodology, called path profiling, was introduced by Ball and Larus in the mid 90s and has received considerable attention in the last 15 years for its practical relevance. A shortcoming of Ball-Larus path profiling was the inability to profile cyclic paths, making it difficult to mine interesting execution patterns that span multiple loop iterations. Previous results, based on rather complex algorithms, have attempted to circumvent this limitation at the price of significant performance losses already for a small number of iterations. In this paper, we present a new approach to multiple iterations path profiling, based on data structures built on top of the original Ball-Larus numbering technique. Our approach allows it to profile all executed paths obtained as a concatenation of up to k Ball-Larus acyclic paths, where k is a user-defined parameter. An extensive experimental investigation on a large variety of Java benchmarks on the Jikes RVM shows that, surprisingly, our approach can be even faster than Ball-Larus due to fewer operations on smaller hash tables, producing compact representations of cyclic paths even for large values of k.
Computational Irreducibility and Computational Analogy
Venue: arXiv cs.CC 2013
Year: 2013

In a previous paper, we provided a formal definition for the concept of computational irreducibility (CIR), i.e. the fact for a function f from N to N that it is impossible to compute f(n) without following approximately the same path than computing successively all the values f(i) from i=1 to n. Our definition is based on the concept of E Turing machines (for Enumerating Turing Machines) and on the concept of approximation of E Turing machines for which we also gave a formal definition. We precise here these definitions through some modifications intended to improve the robustness of the concept. We introduce then a new concept: the Computational Analogy and prove some properties of computationally analog functions. Computational Analogy is an equivalence relation which allows partitioning the set of computable functions in classes whose members have the same properties regarding to their computational irreducibility and their computational complexity.
What Makes Code Hard to Understand?
Venue: arXiv cs.SE 2013
Year: 2013

What factors impact the comprehensibility of code? Previous research suggests that expectation-congruent programs should take less time to understand and be less prone to errors. We present an experiment in which participants with programming experience predict the exact output of ten small Python programs. We use subtle differences between program versions to demonstrate that seemingly insignificant notational changes can have profound effects on correctness and response times. Our results show that experience increases performance in most cases, but may hurt performance significantly when underlying assumptions about related code statements are violated.
Exact-Regenerating Codes between MBR and MSR Points
Venue: arXiv cs.DC 2013
Year: 2013

In this paper we study distributed storage systems with exact repair. We give a construction for regenerating codes between the minimum storage regenerating (MSR) and the minimum bandwidth regenerating (MBR) points and show that in the case that the parameters n, k, and d are close to each other our constructions are close to optimal when comparing to the known capacity when only functional repair is required. We do this by showing that when the distances of the parameters n, k, and d are fixed but the actual values approach to infinity, the fraction of the performance of our codes with exact repair and the known capacity of codes with functional repair approaches to one.
The Worst Case ISI channels and the Uniqueness of the Corresponding Minimum Eigenvalue
Venue: arXiv cs.IT 2013
Year: 2013

Intersymbol interference (ISI) is a major cause of degradation in the receiver performance of high-speed data communications systems. This arises mainly due to limited bandwidth available. The minimum Euclidean distance between any two symbol sequences is an important parameter in this case at moderate to high signal to noise ratios. It is proven here that as ISI increases the minimum distance strictly decreases when the worst case scenario is considered. From this it follows that the minimum eigenvalue of the worst case ISI channel of a given length is unique.
Upper and Lower Bounds for Weak Backdoor Set Detection
Venue: arXiv cs.DS 2013
Year: 2013

We obtain upper and lower bounds for running times of exponential time algorithms for the detection of weak backdoor sets of 3CNF formulas, considering various base classes. These results include (omitting polynomial factors), (i) a 4.54^k algorithm to detect whether there is a weak backdoor set of at most k variables into the class of Horn formulas; (ii) a 2.27^k algorithm to detect whether there is a weak backdoor set of at most k variables into the class of Krom formulas. These bounds improve an earlier known bound of 6^k. We also prove a 2^k lower bound for these problems, subject to the Strong Exponential Time Hypothesis.
GPU Scripting and Code Generation with PyCUDA
Venue: arXiv cs.SE 2013
Year: 2013

High-level scripting languages are in many ways polar opposites to GPUs. GPUs are highly parallel, subject to hardware subtleties, and designed for maximum throughput, and they offer a tremendous advance in the performance achievable for a significant number of computational problems. On the other hand, scripting languages such as Python favor ease of use over computational speed and do not generally emphasize parallelism. PyCUDA is a package that attempts to join the two together. This chapter argues that in doing so, a programming environment is created that is greater than just the sum of its two parts. We would like to note that nearly all of this chapter applies in unmodified form to PyOpenCL, a sister project of PyCUDA, whose goal it is to realize the same concepts as PyCUDA for OpenCL.
Art History on Wikipedia, a Macroscopic Observation
Venue: arXiv cs.SI 2013
Year: 2013

How are articles about art historical actors interlinked within Wikipedia? Lead by this question, we seek an overview on the link structure of a domain specific subset of Wikipedia articles. We use an established domain-specific person name authority, the Getty Union List of Artist Names (ULAN), in order to externally identify relevant actors. Besides containing consistent biographical person data, this database also provides associative relationships between its person records, serving as a reference link structure for comparison. As a first step, we use mappings between the ULAN and English Dbpedia provided by the Virtual Internet Authority File (VIAF). This way, we are able to identify 18,002 relevant person articles. Examining the link structure between these resources reveals interesting insight about the high level structure of art historical knowledge as it is represented on Wikipedia.
Nanoscale photonic network for solution searching and decision making problems
Venue: arXiv cs.ET 2013
Year: 2013

Nature-inspired devices and architectures are attracting considerable attention for various purposes, including the development of novel computing techniques based on spatiotemporal dynamics, exploiting stochastic processes for computing, and reducing energy dissipation. This paper demonstrates that networks of optical energy transfers between quantum nanostructures mediated by optical near-field interactions occurring at scales far below the wavelength of light could be utilized for solving a constraint satisfaction problem (CSP), the satisfiability problem (SAT), and a decision making problem. The optical energy transfer from smaller quantum dots to larger ones, which is a quantum stochastic process, depends on the existence of resonant energy levels between the quantum dots or a state-filling effect occurring at the larger quantum dots. Such a spatiotemporal mechanism yields different evolutions of energy transfer patterns in multi-quantum-dot systems. We numerically demonstrate that networks of optical energy transfers can be used for solution searching and decision making. We consider that such an approach paves the way to a novel physical informatics in which both coherent and dissipative processes are exploited, with low energy consumption.
On the structure and syntactic complexity of generalized definite languages
Venue: arXiv cs.FL 2013
Year: 2013

We give a forbidden pattern characterization for the class of generalized definite languages, show that the corresponding problem is NL-complete and can be solved in quadratic time. We also show that their syntactic complexity coincides with that of the definite languages and give an upper bound of n! for this measure.
On Adaptive Energy Efficient Transmission in WSNs
Venue: arXiv cs.NI 2013
Year: 2013

One of the major challenges in design of Wireless Sensor Networks (WSNs) is to reduce energy consumption of sensor nodes to prolong lifetime of finite-capacity batteries. In this paper, we propose Energy-efficient Adaptive Scheme for Transmission (EAST) in WSNs. EAST is an IEEE 802.15.4 standard compliant. In this scheme, open-loop is used for temperature-aware link quality estimation and compensation. Whereas, closed-loop feedback process helps to divide network into three logical regions to minimize overhead of control packets. Threshold on transmitter power loss (RSSIloss) and current number of nodes (nc(t)) in each region help to adapt transmit power level (Plevel) according to link quality changes due to temperature variation. Evaluation of propose scheme is done by considering mobile sensor nodes and reference node both static and mobile. Simulation results show that propose scheme effectively adapts transmission Plevel to changing link quality with less control packets overhead and energy consumption as compared to classical approach with single region in which maximum transmitter Plevel assigned to compensate temperature variation.
Gaussian Half-Duplex Relay Networks: improved constant gap and connections with the assignment problem
Venue: arXiv cs.IT 2013
Year: 2013

This paper considers a general Gaussian relay network where a source transmits a message to a destination with the help of N half-duplex relays. It proves that the information theoretic cut-set upper bound to the capacity can be achieved to within 2:021(N +2) bits with noisy network coding, thereby reducing the previously known gap. Further improved gap results are presented for more structured networks like diamond networks. It is then shown that the generalized Degrees-of-Freedom of a general Gaussian half-duplex relay network is the solution of a linear program, where the coefficients of the linear inequality constraints are proved to be the solution of several linear programs, known in graph theory as the assignment problem, for which efficient numerical algorithms exist. The optimal schedule, that is, the optimal value of the 2^N possible transmit-receive configurations/states for the relays, is investigated and known results for diamond networks are extended to general relay networks. It is shown, for the case of 2 relays, that only 3 out of the 4 possible states have strictly positive probability. Extensive experimental results show that, for a general N-relay network with N<9, the optimal schedule has at most N +1 states with strictly positive probability. As an extension of a conjecture presented for diamond networks, it is conjectured that this result holds for any HD relay network and any number of relays. Finally, a 2-relay network is studied to determine the channel conditions under which selecting the best relay is not optimal, and to highlight the nature of the rate gain due to multiple relays.
Bargaining for Revenue Shares on Tree Trading Networks
Venue: arXiv cs.GT 2013
Year: 2013

We study trade networks with a tree structure, where a seller with a single indivisible good is connected to buyers, each with some value for the good, via a unique path of intermediaries. Agents in the tree make multiplicative revenue share offers to their parent nodes, who choose the best offer and offer part of it to their parent, and so on; the winning path is determined by who finally makes the highest offer to the seller. In this paper, we investigate how these revenue shares might be set via a natural bargaining process between agents on the tree, specifically, egalitarian bargaining between endpoints of each edge in the tree. We investigate the fixed point of this system of bargaining equations and prove various desirable for this solution concept, including (i) existence, (ii) uniqueness, (iii) efficiency, (iv) membership in the core, (v) strict monotonicity, (vi) polynomial-time computability to any given accuracy. Finally, we present numerical evidence that asynchronous dynamics with randomly ordered updates always converges to the fixed point, indicating that the fixed point shares might arise from decentralized bargaining amongst agents on the trade network.
Exploring Tracer Study Service in Career Center Web Site of Indonesia Higher Education
Venue: arXiv cs.CY 2013
Year: 2013

Quality competence of worker the present do not meet labor market criteria and the low level of labor productivity, the lack of communication between the labor market with education, changing of socio-economic structure and global political influence labor market, the development of science and technology very rapidly lead to fundamental changes in terms of qualifications, competencies and requirements for entering the workforce. Tracer Study results can be used by universities to determine the success of the educational process that has been done towards their students. Therefore, universities need a technology services to support the optimization of the use of tracer study. One of that is the use of a website to facilitate the conduct tracer study. Most services tracer study provides information to college, like year graduated, got a job waiting period, the first salary to work, first job, the relevance of the curriculum to the work, and compliance with the major areas of work taken in college. Tracer study feature in Career Center Website affect the popularity website especially in traffic and rich file website.
On Partial Vertex Cover on Bipartite Graphs and Trees
Venue: arXiv cs.CC 2013
Year: 2013

It is well-known that the Vertex Cover problem is in P on bipartite graphs, however; the computational complexity of the Partial Vertex Cover problem on bipartite graphs is open. In this paper, we first show that the Partial Vertex Cover problem is NP-hard on bipartite graphs. We then identify an interesting special case of bipartite graphs, for which the Partial Vertex Cover problem can be solved in polynomial-time. We also show that the set of acyclic bipartite graphs, i.e., forests, and the set of bipartite graph where the degree of each vertex is at most 3 fall into that special case. Therefore, we prove that the Partial Vertex Cover problem is in P on trees, and it is also in P on the set of bipartite graphs where the degree of each vertex is at most 3.
Dynamic stochastic blockmodels: Statistical models for time-evolving networks
Venue: arXiv cs.SI 2013
Year: 2013

Significant efforts have gone into the development of statistical models for analyzing data in the form of networks, such as social networks. Most existing work has focused on modeling static networks, which represent either a single time snapshot or an aggregate view over time. There has been recent interest in statistical modeling of dynamic networks, which are observed at multiple points in time and offer a richer representation of many complex phenomena. In this paper, we propose a state-space model for dynamic networks that extends the well-known stochastic blockmodel for static networks to the dynamic setting. We then propose a procedure to fit the model using a modification of the extended Kalman filter augmented with a local search. We apply the procedure to analyze a dynamic social network of email communication.