OpenRaiser/Intern-Atlas huggingface dataset:
New Guidelines For Spreadsheets
Venue: arXiv cs.HC 2008
Year: 2008

Current prescriptions for spreadsheet style specify modular separation of data, calcu1ation and output, based on the notion that writing a spreadsheet is like writing a computer program. Instead of a computer programming style, this article examines rules of style for text, graphics, and mathematics. Much 'common wisdom' in spreadsheets contradicts rules for these well-developed arts. A case is made here for a new style for spreadsheets that emphasises readability. The new style is described in detail with an example, and contrasted with the programming style.
On algebras admitting a complete set of near weights, evaluation codes and Goppa codes
Venue: arXiv cs.IT 2008
Year: 2008

In 1998 Hoholdt, van Lint and Pellikaan introduced the concept of a ``weight function'' defined on a F_q-algebra and used it to construct linear codes, obtaining among them the algebraic-geometric (AG) codes supported on one point. Later it was proved by Matsumoto that all codes produced using a weight function are actually AG codes supported on one point. Recently, ``near weight functions'' (a generalization of weight functions), also defined on a F_q-algebra, were introduced to study codes supported on two points. In this paper we show that an algebra admits a set of m near weight functions having a compatibility property, namely, the set is a ``complete set'', if and only if it is the ring of regular functions of an affine geometrically irreducible algebraic curve defined over F_q whose points at infinity have a total of m rational branches. Then the codes produced using the near weight functions are exactly the AG codes supported on m points. A formula for the minimum distance of these codes is presented with examples which show that in some situations it compares better than the usual Goppa bound.
Relational Lattice Axioms
Venue: arXiv cs.DB 2008
Year: 2008

Relational lattice is a formal mathematical model for Relational algebra. It reduces the set of six classic relational algebra operators to two: natural join and inner union. We continue to investigate Relational lattice properties with emphasis onto axiomatic definition. New results include additional axioms, equational definition for set difference (more generally anti-join), and case study demonstrating application of the relational lattice theory for query transformations.
Pseudo-random Sequences Generated by Cellular Automata
Venue: arXiv cs.DM 2008
Year: 2008

Generation of pseudo random sequences by cellular automata, as well as by hybrid cellular automata is surveyed. An application to the fast evaluation and FPGA implementation of some classes of boolean functions is sketched out.
Topology and Geometry of Online Social Networks
Venue: arXiv cs.CY 2008
Year: 2008

In this paper, we study certain geometric and topological properties of online social networks using the concept of density and geometric vector spaces. "Moi Krug" ("My Circle"), a Russian social network that promotes the principle of the "six degrees of separation" and is positioning itself as a vehicle for professionals and recruiters seeking each others' services, is used as a test vehicle.
An Image-Based Sensor System for Autonomous Rendez-Vous with Uncooperative Satellites
Venue: arXiv cs.CV 2008
Year: 2008

In this paper are described the image processing algorithms developed by SENER, Ingenieria y Sistemas to cope with the problem of image-based, autonomous rendez-vous (RV) with an orbiting satellite. The methods developed have a direct application in the OLEV (Orbital Life Extension Extension Vehicle) mission. OLEV is a commercial mission under development by a consortium formed by Swedish Space Corporation, Kayser-Threde and SENER, aimed to extend the operational life of geostationary telecommunication satellites by supplying them control, navigation and guidance services. OLEV is planned to use a set of cameras to determine the angular position and distance to the client satellite during the complete phases of rendez-vous and docking, thus enabling the operation with satellites not equipped with any specific navigational aid to provide support during the approach. The ability to operate with un-equipped client satellites significantly expands the range of applicability of the system under development, compared to other competing video technologies already tested in previous spatial missions, such as the ones described here below.
A Logical Model and Data Placement Strategies for MEMS Storage Devices
Venue: arXiv cs.DB 2008
Year: 2008

MEMS storage devices are new non-volatile secondary storages that have outstanding advantages over magnetic disks. MEMS storage devices, however, are much different from magnetic disks in the structure and access characteristics. They have thousands of heads called probe tips and provide the following two major access facilities: (1) flexibility: freely selecting a set of probe tips for accessing data, (2) parallelism: simultaneously reading and writing data with the set of probe tips selected. Due to these characteristics, it is nontrivial to find data placements that fully utilize the capability of MEMS storage devices. In this paper, we propose a simple logical model called the Region-Sector (RS) model that abstracts major characteristics affecting data retrieval performance, such as flexibility and parallelism, from the physical MEMS storage model. We also suggest heuristic data placement strategies based on the RS model and derive new data placements for relational data and two-dimensional spatial data by using those strategies. Experimental results show that the proposed data placements improve the data retrieval performance by up to 4.0 times for relational data and by up to 4.8 times for two-dimensional spatial data of approximately 320 Mbytes compared with those of existing data placements. Further, these improvements are expected to be more marked as the database size grows.
Lower Bounds for Embedding into Distributions over Excluded Minor Graph Families
Venue: arXiv cs.DS 2008
Year: 2008

It was shown recently by Fakcharoenphol et al that arbitrary finite metrics can be embedded into distributions over tree metrics with distortion O(log n). It is also known that this bound is tight since there are expander graphs which cannot be embedded into distributions over trees with better than Omega(log n) distortion. We show that this same lower bound holds for embeddings into distributions over any minor excluded family. Given a family of graphs F which excludes minor M where |M|=k, we explicitly construct a family of graphs with treewidth-(k+1) which cannot be embedded into a distribution over F with better than Omega(log n) distortion. Thus, while these minor excluded families of graphs are more expressive than trees, they do not provide asymptotically better approximations in general. An important corollary of this is that graphs of treewidth-k cannot be embedded into distributions over graphs of treewidth-(k-3) with distortion less than Omega(log n). We also extend a result of Alon et al by showing that for any k, planar graphs cannot be embedded into distributions over treewidth-k graphs with better than Omega(log n) distortion.
Research Challenges in Management and Compliance of Policies on the Web
Venue: arXiv cs.CY 2008
Year: 2008

In this paper we argue that policies are an increasing concern for organizations that are operating a web site. Examples of policies that are relevant in the domain of the web address issues such as privacy of personal data, accessibility for the disabled, user conduct, e-commerce, and intellectual property. Web site policies--and the overarching concept of web site governance--are cross-cutting concerns that have to be addressed and implemented at different levels (e.g., policy documents, legal statements, business processes, contracts, auditing, and software systems). For web sites, policies are also reflected in the legal statements that the web site posts, and in the behavior and features that the web site offers to its users. Both policies and software tend to evolve independently, but at the same time they both have to be kept in sync. This is a practical challenge for operators of web sites that is poorly addressed right now and is, we believe, a promising avenue for future research. In this paper, we discuss various challenges that policy poses for web sites with an emphasis on privacy and data protection and identify open issues for future research.
I'm sorry to say, but your understanding of image processing fundamentals is absolutely wrong
Venue: arXiv cs.AI 2008
Year: 2008

The ongoing discussion whether modern vision systems have to be viewed as visually-enabled cognitive systems or cognitively-enabled vision systems is groundless, because perceptual and cognitive faculties of vision are separate components of human (and consequently, artificial) information processing system modeling.
DMT of Multi-hop Cooperative Networks - Part II: Half-Duplex Networks with Full-Duplex Performance
Venue: arXiv cs.IT 2008
Year: 2008

We consider single-source single-sink (ss-ss) multi-hop relay networks, with slow-fading links and single-antenna half-duplex relay nodes. In a companion paper, we established some basic results which laid the foundation for the results presented here. In the present paper, we consider two families of networks of half-duplex networks. KPP networks may be viewed as the union of K node-disjoint parallel relaying paths. Generalizations of these networks include KPP(I) networks, which permit interference between paths and KPP(D) networks, which possess a direct link between source and sink. We characterize the DMT of these families of networks completely and show that they can achieve the cut-set bound, thus proving that full-duplex performance can be obtained even in the presence of the half-duplex constraint. We then consider layered networks, and prove that a linear DMT between maximum diversity and maximum multiplexing gain is achievable. All protocols in this paper are explicit and use only amplify-and-forward relaying. We also construct codes that achieve the optimal DMT for all the proposed schemes. Two key implications of the results in the paper are that the half-duplex constraint does not entail any rate loss for a large class of cooperative networks and that AF protocols are often optimal.
Towards a Process for Developing Maintenance Tools in Academia
Venue: arXiv cs.SE 2008
Year: 2008

Building of tools--from simple prototypes to industrial-strength applications--is a pervasive activity in academic research. When proposing a new technique for software maintenance, effective tool support is typically required to demonstrate the feasibility and effectiveness of the approach. However, even though tool building is both pervasive and requiring significant time and effort, it is still pursued in an ad hoc manner. In this paper, we address these issues by proposing a dedicated development process for tool building that takes the unique characteristics of an academic research environment into account. We first identify process requirements based on a review of the literature and our extensive tool building experience in the domain of maintenance tools. We then outline a process framework based on work products that accommodates the requirements while providing needed flexibility for tailoring the process to account for specific tool building approaches and project constraints. The work products are concrete milestones of the process, tracking progress, rationalizing (design) decisions, and documenting the current state of the tool building project. Thus, the work products provide important input for strategic project decisions and rapid initiation of new team members. Leveraging a dedicated tool building process promises tools that are designed, build, and maintained in a more disciplined, predictable and efficient manner.
Building a terminology network for search: the KoMoHe project
Venue: arXiv cs.DL 2008
Year: 2008

The paper reports about results on the GESIS-IZ project "Competence Center Modeling and Treatment of Semantic Heterogeneity" (KoMoHe). KoMoHe supervised a terminology mapping effort, in which 'cross-concordances' between major controlled vocabularies were organized, created and managed. In this paper we describe the establishment and implementation of cross-concordances for search in a digital library (DL).
Mutual information is copula entropy
Venue: arXiv cs.IT 2008
Year: 2008

We prove that mutual information is actually negative copula entropy, based on which a method for mutual information estimation is proposed.
Graham's Schedules and the Number Partition Problem
Venue: arXiv cs.CC 2008
Year: 2008

We show the equivalence of the Number Partition Problem and the two processor scheduling problem. We establish a priori bounds on the completion times for the scheduling problem which are tighter than Graham's but almost on par with a posteriori bounds of Coffman and Sethi. We conclude the paper with a characterization of the asymptotic behavior of the scheduling problem which relates to the spread of the processing times and the number of jobs.
Dynamic Connectivity: Connecting to Networks and Geometry
Venue: arXiv cs.DS 2008
Year: 2008

Dynamic connectivity is a well-studied problem, but so far the most compelling progress has been confined to the edge-update model: maintain an understanding of connectivity in an undirected graph, subject to edge insertions and deletions. In this paper, we study two more challenging, yet equally fundamental problems. Subgraph connectivity asks to maintain an understanding of connectivity under vertex updates: updates can turn vertices on and off, and queries refer to the subgraph induced by "on" vertices. (For instance, this is closer to applications in networks of routers, where node faults may occur.) We describe a data structure supporting vertex updates in O (m^{2/3}) amortized time, where m denotes the number of edges in the graph. This greatly improves over the previous result [Chan, STOC'02], which required fast matrix multiplication and had an update time of O(m^0.94). The new data structure is also simpler. Geometric connectivity asks to maintain a dynamic set of n geometric objects, and query connectivity in their intersection graph. (For instance, the intersection graph of balls describes connectivity in a network of sensors with bounded transmission radius.) Previously, nontrivial fully dynamic results were known only for special cases like axis-parallel line segments and rectangles. We provide similarly improved update times, O (n^{2/3}), for these special cases. Moreover, we show how to obtain sublinear update bounds for virtually all families of geometric objects which allow sublinear-time range queries, such as arbitrary 2D line segments, d-dimensional simplices, and d-dimensional balls.
Commonsense Knowledge, Ontology and Ordinary Language
Venue: arXiv cs.AI 2008
Year: 2008

Over two decades ago a "quite revolution" overwhelmingly replaced knowledgebased approaches in natural language processing (NLP) by quantitative (e.g., statistical, corpus-based, machine learning) methods. Although it is our firm belief that purely quantitative approaches cannot be the only paradigm for NLP, dissatisfaction with purely engineering approaches to the construction of large knowledge bases for NLP are somewhat justified. In this paper we hope to demonstrate that both trends are partly misguided and that the time has come to enrich logical semantics with an ontological structure that reflects our commonsense view of the world and the way we talk about in ordinary language. In this paper it will be demonstrated that assuming such an ontological structure a number of challenges in the semantics of natural language (e.g., metonymy, intensionality, copredication, nominal compounds, etc.) can be properly and uniformly addressed.
Self-Motions of General 3-RPR Planar Parallel Robots
Venue: arXiv cs.RO 2008
Year: 2008

This paper studies the kinematic geometry of general 3-RPR planar parallel robots with actuated base joints. These robots, while largely overlooked, have simple direct kinematics and large singularity-free workspace. Furthermore, their kinematic geometry is the same as that of a newly developed parallel robot with SCARA-type motions. Starting from the direct and inverse kinematic model, the expressions for the singularity loci of 3-RPR planar parallel robots are determined. Then, the global behaviour at all singularities is geometrically described by studying the degeneracy of the direct kinematic model. Special cases of self-motions are then examined and the degree of freedom gained in such special configurations is kinematically interpreted. Finally, a practical example is discussed and experimental validations performed on an actual robot prototype are presented.
A Novel Symbolic Type Neural Network Model- Application to River Flow Forecasting
Venue: arXiv cs.NE 2008
Year: 2008

In this paper we introduce a new symbolic type neural tree network called symbolic function network (SFN) that is based on using elementary functions to model systems in a symbolic form. The proposed formulation permits feature selection, functional selection, and flexible structure. We applied this model on the River Flow forecasting problem. The results found to be superior in both fitness and sparsity.
Image Steganography, a New Approach for Transferring Security Information
Venue: arXiv cs.CR 2008
Year: 2008

Steganography is the art of hiding the fact that communication is taking place, by hiding information in other information. Many different carrier file formats can be used, but digital images are the most popular because of their frequency on the Internet. For hiding secret information in images, there exists a large variety of steganographic techniques some are more complex than others and all of them have respective strong and weak points. Different applications have different requirements of the steganography technique used. For example, some applications may require absolute invisibility of the secret information, while others require a larger secret message to be hidden. This paper intends to give an overview of image steganography, its uses and techniques. It also attempts to identify the requirements of a good steganographic algorithm and briefly reflects on which steganographic techniques are more suitable for which applications.
Nearly Tight Low Stretch Spanning Trees
Venue: arXiv cs.DS 2008
Year: 2008

We prove that any graph $G$ with $n$ points has a distribution $\mathcal{T}$ over spanning trees such that for any edge $(u,v)$ the expected stretch $E_{T \sim \mathcal{T}}[d_T(u,v)/d_G(u,v)]$ is bounded by $\tilde{O}(\log n)$. Our result is obtained via a new approach of building ``highways'' between portals and a new strong diameter probabilistic decomposition theorem.
Comparing human and automatic thesaurus mapping approaches in the agricultural domain
Venue: arXiv cs.DL 2008
Year: 2008

Knowledge organization systems (KOS), like thesauri and other controlled vocabularies, are used to provide subject access to information systems across the web. Due to the heterogeneity of these systems, mapping between vocabularies becomes crucial for retrieving relevant information. However, mapping thesauri is a laborious task, and thus big efforts are being made to automate the mapping process. This paper examines two mapping approaches involving the agricultural thesaurus AGROVOC, one machine-created and one human created. We are addressing the basic question "What are the pros and cons of human and automatic mapping and how can they complement each other?" By pointing out the difficulties in specific cases or groups of cases and grouping the sample into simple and difficult types of mappings, we show the limitations of current automatic methods and come up with some basic recommendations on what approach to use when.
Wet Paper Coding for Watermarking of Binary Images
Venue: arXiv cs.IT 2008
Year: 2008

We propose a new method to embed data in binary images, including scanned text, figures, and signatures. Our method relies on the concept of wet paper codes. The shuffling before embedding is used in order to equalize irregular embedding capacity from diverse areas in the image. The hidden data can be extracted without the original binary image. We illustrate some examples of watermarked binary images after wet paper coding.
Report on the "Secure Vehicular Communications: Results and Challenges Ahead" Workshop
Venue: arXiv cs.CR 2008
Year: 2008

This is a report and a collection of abstracts from the Feb. 2008 Lausanne Workshop on Secure Vehicular Communication Systems.
n-ary Fuzzy Logic and Neutrosophic Logic Operators
Venue: arXiv cs.AI 2008
Year: 2008

We extend Knuth's 16 Boolean binary logic operators to fuzzy logic and neutrosophic logic binary operators. Then we generalize them to n-ary fuzzy logic and neutrosophic logic operators using the smarandache codification of the Venn diagram and a defined vector neutrosophic law. In such way, new operators in neutrosophic logic/set/probability are built.
Approximate capacity of the two-way relay channel: A deterministic approach
Venue: arXiv cs.IT 2008
Year: 2008

We study the capacity of the full-duplex bidirectional (or two-way) relay channel with two nodes and one relay. The channels in the forward direction are assumed to be different (in general) than the channels in the backward direction, i.e. channel reciprocity is not assumed. We use the recently proposed deterministic approach to capture the essence of the problem and to determine a good transmission and relay strategy for the Gaussian channel. Depending on the ratio of the individual channel gains, we propose to use either a simple amplify-and-forward or a particular superposition coding strategy at the relay. We analyze the achievable rate region and show that the scheme achieves to within 3 bits the cut-set bound for all values of channel gains.
Confirmation Bias and the Open Access Advantage: Some Methodological Suggestions for the Davis Citation Study
Venue: arXiv cs.DL 2008
Year: 2008

Davis (2008) analyzes citations from 2004-2007 in 11 biomedical journals. 15% of authors paid to make them Open Access (OA). The outcome is a significant OA citation Advantage, but a small one (21%). The author infers that the OA advantage has been shrinking yearly, but the data suggest the opposite. Further analyses are necessary: (1) Not just author-choice (paid) OA but Free OA self-archiving needs to be taken into account rather than being counted as non-OA. (2) proportion of OA articles per journal per year needs to be reported and taken into account. (3) The Journal Impact Factor and the relation between the size of the OA Advantage article 'citation-bracket' need to be taken into account. (4) The sample-size for the highest-impact, largest-sample journal analyzed, PNAS, is restricted and excluded from some of the analyses. The full PNAS dataset is needed. (5) The interaction between OA and time, 2004-2007, is based on retrospective data from a June 2008 total cumulative citation count. The dates of both the cited articles and the citing articles need to be taken into account. The author proposes that author self-selection bias for is the primary cause of the observed OA Advantage, but this study does not test this or of any of the other potential causal factors. The author suggests that paid OA is not worth the cost, per extra citation. But with OA self-archiving both the OA and the extra citations are free.