ppxscal/embedding_network huggingface dataset:
Generalizing consistency and other constraint properties to quantified constraints
Authors: Lucas Bordeaux, Marco Cadoli, Toni Mancini
Venue: ACM Transactions on Computational Logic (TOCL) (2009)

Quantified constraints and Quantified Boolean Formulae are typically much more difficult to reason with than classical constraints, because quantifier alternation makes the usual notion of solution inappropriate. As a consequence, basic properties of Constraint Satisfaction Problems (CSPs), such as consistency or substitutability, are not completely understood in the quantified case. These properties are important because they are the basis of most of the reasoning methods used to solve classical (existentially quantified) constraints, and it is desirable to benefit from similar reasoning methods in the resolution of quantified constraints. In this article, we show that most of the properties that are used by solvers for CSP can be generalized to quantified CSP. This requires a rethinking of a number of basic concepts; in particular, we propose a notion of outcome that generalizes the classical notion of solution and on which all definitions are based. We propose a systematic study of the relations which hold between these properties, as well as complexity results regarding the decision of these properties. Finally, and since these problems are typically intractable, we generalize the approach used in CSP and propose weaker, easier to check notions based on locality, which allow to detect these properties incompletely but in polynomial time.
Brief paper: Minimization of the effect of noisy measurements on localization of multi-agent autonomous formations
Authors: Iman Shames, Barış Fidan, Brian D. O. Anderson
Venue: Automatica (Journal of IFAC) (2009)

This paper considers the problem of reduction of self-localization errors in multi-agent autonomous formations when only distance measurements are available to the agents in a globally rigid formation. It is shown that there is a relationship between different selections of anchors, agents with exactly known positions, and the error induced by measurement error on localization solution. This fact is exploited to develop a mechanism to select anchors in order to minimize the effects of inter-agent distance measurement errors on localization solution. Finally, some simulation results are presented to demonstrate the optimal anchor selection for a particular general class of formations, the globally rigid formations.
A Bialgebraic Approach to Automata and Formal Language Theory
Authors: James Worthington
Venue: Proceedings of the 2009 International Symposium on Logical Foundations of Computer Science (2009)

A bialgebra is a structure which is simultaneously an algebra and a coalgebra, such that the algebraic and coalgebraic parts are "compatible". In this paper, we apply the defining diagrams of algebras, coalgebras, and bialgebras to categories of semimodules and semimodule homomorphisms over a commutative semiring. We then show that formal language theory and the theory of bialgebras have essentially undergone "convergent evolution". For example, formal languages correspond to elements of dual algebras of coalgebras, automata are "pointed representation objects" of algebras, automaton morphisms are instances of linear intertwiners, and a construction from the theory of bialgebras shows how to run two automata in parallel. We also show how to associate an automaton with an arbitrary algebra, which in the classical case yields the automaton whose states are formal languages and whose transitions are given by language differentiation. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Within bounds and between domains: Reflecting on Making Tea within the context of design elicitation methods
Authors: m. c. schraefel, Alan Dix
Venue: International Journal of Human-Computer Studies (2009)

Making Tea (MT) is a design elicitation method developed in eScience specifically to deal with situations in which (1) the designers do not share domain or artifact knowledge with design-domain experts, (2) the processes in the space are semi-structured and (3) the processes to be modeled can last for periods exceeding the availability of most ethnographers. We have used the method in two distinct eScience contexts, and may offer an effective, low cost way to deal with bridging between software design teams and scientists to develop useful and usable eScience artifacts. To that end, we propose a set of criteria in order to understand why MT works. Through these criteria we also reflect upon the relation of MT to other design elicitation methods in order to propose a kind of method framework from which other designers may be assisted in choosing elicitation methods and in developing new methods both for eScience contexts and beyond.
Salvaging your software asset: (tools based maintenance)
Authors: Michael J. Lyons
Venue: Proceedings of the May 4-7, 1981, national computer conference (1981)

Software is a valuable asset embodying decision processes of an organization and contributing directly to the means of production. Maintenance is the mechanism for combating deterioration of that software asset, which over time tends to become arthritic and inflexible to change. Maintenance, though extremely costly, is essential to insuring the viability of the organization. Both rewrites and purchased software, with ensuing conversions, are usually not a cost-effective solution to software decay. Structured retrofit is an effective alternative, using a software tools-based methodology for combating decay and the high costs of maintenance. The critical tool is the COBOL structured programming engine. With it, spaghetti code software is mechanically transformed to well-structured programs, whose ongoing maintenance reaps the benefits of the structured programming methodologies.
A Method of Number-Plate Character Recognition Algorithm Based on Boosting Classification
Authors: Chen Yuan-yuan, Li Jing
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 03 (2009)

A method of number-plate characters recognition using AdaBoost algorithm, which based on template matching is presented in order to improve recognition rate and reduce recognition time. The method is divided into two stages. In the first stage, classifier is trained by template matching which is improved through AdaBoost classification, at the same time, classification rules are found. Number-plate characters are recognized by classification rules and then classification results are obtained in the second stage. The experiment results have showed that, for a vehicle number-plate, recognition rate of characters is more than 90% and the recognition time of characters is less than 2 second by using the method.
Foucault's corollary: agency theory and the economics of self-monitoring
Authors: Nilmini Wickramasinghe, Roberta Lamb
Venue: International Journal of Networking and Virtual Organisations (2009)

In a knowledge economy, the management of an organisation's human capital is critical and prudent management often translates into the attainment of a sustainable competitive advantage. The interaction of knowledge workers with Information and Communication Technologies (ICTs) has presented a particularly interesting dynamic to researchers who study changes in related behavioural phenomena. One such phenomenon is self-monitoring. This paper examines the economics of self-monitoring and the integral role of ICTs in enabling knowledge workers to self-monitor. By merging Foucault's power/knowledge ideas with classical agency theory, we gain a richer understanding of human capital dynamics in a knowledge economy.
Computing sharp bounds for hard clustering problems on trees
Authors: Isabella Lari, Maurizio Maravalle, Bruno Simeone
Venue: Discrete Applied Mathematics (2009)

Clustering problems with relational constraints in which the underlying graph is a tree arise in a variety of applications: hierarchical data base paging, communication and distribution networks, districting, biological taxonomy, and others. They are formulated here as optimal tree partitioning problems. In a previous paper, it was shown that their computational complexity strongly depends on the nature of the objective function and, in particular, that minimizing the total within-cluster dissimilarity or the diameter is computationally hard. We propose heuristics that find good partitions within a reasonable time, even for instances of relatively large size. Such heuristics are based on the solution of continuous relaxations of certain integer (or almost integer) linear programs. Experimental results on over 2000 randomly generated instances with up to 500 entities show that the values (total within-cluster dissimilarity or diameter) of the solutions provided by these heuristics are quite close to the minimum one.
Merit functions in vector optimization
Authors: C. G. Liu, K. F. Ng, W. H. Yang
Venue: Mathematical Programming: Series A and B (2009)

We study the weak domination property and weakly efficient solutions in vector optimization problems. In particular scalarization of these problems is obtained by virtue of some suitable merit functions. Some natural conditions to ensure the existence of error bounds for merit functions are also given.
Combining recurrent neural networks with eigenvector methods for classification of ECG beats
Authors: Elif Derya Übeyli
Venue: Digital Signal Processing (2009)

The purpose of this study is to evaluate the accuracy of the recurrent neural networks (RNNs) trained with Levenberg-Marquardt algorithm on the electrocardiogram (ECG) beats. Four types of ECG beats (normal beat, congestive heart failure beat, ventricular tachyarrhythmia beat, atrial fibrillation beat) obtained from the Physiobank database were analyzed. Decision making was performed in two stages: feature extraction by eigenvector methods and classification using the RNN trained on the extracted features. The RNNs were implemented for classification of the ECG beats using the statistical features as inputs. The ability of designed and trained Elman RNNs, combined with eigenvector methods, were explored to classify the ECG beats. The classification results demonstrated that the combined eigenvector methods/RNN approach can be useful in analyzing the ECG beats.
Throughput Improvement with Discrete Pilot Signal Assignment and Iterative Channel Identification for MQRD-PCM/OFDM
Authors: Chang-Jun Ahn
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

In MIMO systems, the channel identification is important to distinguish transmitted signals from multiple transmit antennas. One of the most typical channel identification schemes is to employ a code division multiplexing (CDM) based scheme in which a unique spreading code is assigned to distinguish both BS and MS antenna elements. However, by increasing the number of base stations and transmit antenna elements, large spreading codes and pilot symbols are required to distinguish the received power from all the connectable BS, as well as to identify all the CSI for the combination of transmitter and receiver antenna elements. Furthermore, the complexity of maximum likelihood detection (MLD) for implementation of MIMO is a considerable work. To reduce these problems, in this paper, we propose the parallel detection algorithm using multiple QR decompositions with permuted channel matrix (MQRD-PCM) with discrete pilot signal assignment and iterative channel identification for MIMO/OFDM.
Constrained minimum enclosing circle with center on a query line segment
Authors: Sasanka Roy, Arindam Karmakar, Sandip Das, Subhas C. Nandy
Venue: Computational Geometry: Theory and Applications (2009)

In this paper, we will study the problem of locating the center of the smallest enclosing circle of a set P of n points, where the center is constrained to lie on a query line segment. The preprocessing time and space complexities of our proposed algorithm are O(nlogn) and O(n) respectively; the query time complexity is O(log^2n).
Resolving CSP with Naming Games
Authors: Giorgio Gosti
Venue: Proceedings of the 24th International Conference on Logic Programming (2008)

In constraint satisfaction problems (CSP) we consider N variables x 1,x 2, ...x N , their definition domains D 1,D 2, ...,D N and a set of constraints on the values of these variables; solving the CSP means finding a particular value for the variables that satisfies the constraints. In the distributed CSP (DCSP) as defined by Makoto Yokoo [1], the variables of the CSP are distributed among the agents. These agents are able to communicate between themselves and know all the constraint predicates relevant to their variable. The agents through interaction find the appropriate values to solve the CSP.The naming game describes a set of problems in which a number N of agents bootstrap a commonly agreed name for an object. Each naming game is defined by an interaction protocol/algorithm. An important aspect of the naming game is the hierarchy-free agent architecture. For other references on the naming game see the work of Steels [3] and Baronchelli et al. [2].
Keynote lecture III: algorithms for rendering depth of field effects for synthetic image generation and computational photography
Authors: Brian A. Barsky
Venue: Proceedings of the 12th WSEAS international conference on Computers (2008)

Depth of field refers to the swath through a 3D scene that is imaged in acceptable focus through an optics system, such as a camera lens. It is a vitally important component of real photographs, and is useful as a tool for drawing the viewer's eye to the important part of the image. Depth of field is equally important for computer-generated images. This talk will provide an explanation of the phenomenon of depth of field and a survey of a variety of techniques to render depth of field effects in computer graphics, with particular attention devoted to the trade-offs between image quality and algorithm efficiency. Algorithms to render highly accurate depth of field effects, such as distributed ray tracing or the accumulation buffer, are sampling methods that use large numbers of samples, with high computational cost. Sampling is inherently slow because it effectively requires rendering the scene many times, which multiplies the render time by a potentially large factor. Faster algorithms are based on a post processing approach, which operates in image space. Post process methods operate on 2D images along with depth information, rather than working with a full 3D object representation as the sampling methods do. Consequently, post process methods struggle to accurately simulate the underlying optical process, and tend to suffer from artifacts or avoid those artifacts at a large cost. The talk will include an analysis of the nature of these artifacts.
GERAN Evolution: Multi-User Reusing One Slot to Improve Capacity
Authors: Xiang Chen, Zesong Fei, Jingming Kuang, Keke Liu, Meng Zheng
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 01 (2009)

The increase in user amount and voice traffic puts a huge pressure on GSM/EDGE networks especially within populous countries. A newly proposed concept, multi-user reusing one slot (MUROS), would help operators in densely populated cities to alleviate the strain on their networks. The key idea of MUROS is to multiplex two or more users onto one time slot. We improved one downlink (DL) MUROS solution, two users coexist in one TCH (Co-TCH), by proposing the scheme named MSK-based orthogonal pair (MSK-OP) in this paper. Theoretical analysis and simulation results shows that MSK-OP is a promising scheme of MUROS due to its ability to double the peak voice capacity of GSM networks without degrading the speech quality very much.
Quality-Based Score Normalization and Frame Selection for Video-Based Person Authentication
Authors: Enrique Argones Rúa, José Luis Alba Castro, Carmen García Mateo
Venue: Biometrics and Identity Management: First European Workshop, BIOID 2008, Roskilde, Denmark, May 7-9, 2008. Revised Selected Papers (2008)

This paper addresses the incorporation of quality measures to video-based person authentication. A theoretical framework to incorporate quality measures in biometric authentication is exposed. Two different quality-based score normalization techniques are derived from this theoretical framework. Furthermore, a quality-based frame selection technique and a new face image quality measure are also presented. The ability of this quality measure and the proposed quality-based score normalization techniques and quality-based frame selection technique to improve verification performance is experimentally evaluated in a video-based face verification experiment on the BANCA Database.
Adaptive pricing for resource reservations in Shared environments
Authors: Gurmeet Singh, Carl Kesselman, Ewa Deelman
Venue: Proceedings of the 8th IEEE/ACM International Conference on Grid Computing (2007)

Application scheduling studies on large-scale shared resources have advocated the use of resource provisioning in the form of advance reservations for providing predictable and deterministic quality of service to applications. Resource scheduling studies however have shown the adverse impact of advance reservations in the form of reduced utilization and increased response time of the resources. Thus, resource providers either disallow reservations or impose restrictions such as minimum notice periods and this reduces the effectiveness of reservations as the means of allocating desired resources at a desired time. In this paper, we suggest adaptive pricing as an alternative for allowing reservation of resources. The price charged for allowing a reservation is based directly on the impact that the reservation has on other users sharing the resource. Using trace-based simulations, we show that adaptive pricing allows users to make reservations at the desired time while making it more expensive than best effort service. Thus, users are induced to make the correct choice between reservations and best-effort service based on their real needs. Moreover, this pricing scheme is more cost effective and sensitive to the system load as compared to a flat pricing scheme and encourages load balancing across resources.
Forecasting the probability of finding oil slicks using a CBR system
Authors: Aitor Mata, Juan Manuel Corchado
Venue: Expert Systems with Applications: An International Journal (2009)

A new predicting system is presented in which the aim is to forecast the presence of oil slicks in a certain area of the open sea after an oil spill. Case-based reasoning is a computational methodology designed to generate solutions to a certain problem by analysing previous solutions given to previous solved problems. In this case, the system designed to predict the presence of oil slicks wraps other artificial intelligence techniques such as a radial basis function networks, growing cell structures and principal components analysis in order to develop the different phases of the Case-based reasoning cycle. The proposed system uses information such as sea salinity, sea temperature, wind, currents, pressure, number and area of the slicks,.... obtained from various satellites. The system has been trained using data obtained after the Prestige oil spill, occurred in the Atlantic waters, in the northwest of Spain. The system developed has been able to accurately predict the presence of oil slicks in the north west of the Galician coast, using historical data.
Shoebox: mixing storage and display of digital images in the home
Authors: Richard Banks, Abigail Sellen
Venue: Proceedings of the 3rd International Conference on Tangible and Embedded Interaction (2009)

This paper describes the rationale and design process for Shoebox, a "digital box" that combines the storage and display of digital images in the home in one unit. By combining these two functions in one, Shoebox attempts to bridge the divide between the location within a home where digital content is typically stored, and the means by which it can be put on display, as well as provide a form factor that encourages co-located sharing of images.
The size of maximal systems of square islands
Authors: Zsolt Lengvárszky
Venue: European Journal of Combinatorics (2009)

For integers m>0,n>0, and , a set H of closed rectangles that are all subsets of R and the vertices of which have integer coordinates is called a system of rectangular islands if for every pair of rectangles in H one of them contains the other or they do not overlap at all. Let IR denote the ordered set of systems of rectangular islands on R, and let max(IRIRf(m,n)=max{|H|: H∈max(IR)}, G. Czédli [G. Czédli, The number of rectangular islands by means of distributive lattices, European Journal of Combinatorics, in press (doi:10.1016/j.ejc.2008.02.005)] proved f(m,n)=[(mn+m+n-1)/2@]. For g(m,n)=min{|H|:H∈max(IR )} in [Z. Lengvárszky, The minimum cardinality of maximal systems of rectangular islands, European Journal of Combinatorics 30 (1) 216-219], we proved g(m,n)=m+n-1. Systems of square islands are systems of rectangular islands with R and all members of H being squares. The functions f(n) and g(n) are defined analogously to f(m,n) and g(m,n), and we show f(n)≤n(n+2)/3 (best polynomial bound), and g(n)=n.
Mumford&#x2013;Shah based registration: a comparison of a level set and a phase field approach
Authors: Marc Droske, Wolfgang Ring, Martin Rumpf
Venue: Computing and Visualization in Science (2009)

Traditionally, different image processing tasks are mainly considered on their own. The main aim of this paper is a combination of registration, i.e., the spatial alignment of images and egmentation, i.e., the recognition of edges and object contours in images. A proper registration depends on a good initial segmentation and vice versa. In this paper, it is proposed to link these problems together by formulating a coupled variational problem. We will focus on an edge-based approach instead of considering image intensities and propose a variational formulation based on the Mumford&#x2013;Shah free discontinuity problem. This paper is particularly devoted to a comparison of a sharp interface approach with the phase field analogue.
Experimental evaluation of an educational game for improved learning in introductory computing
Authors: Michael Eagle, Tiffany Barnes
Venue: ACM SIGCSE Bulletin (2009)

We are developing games to increase student learning and attitudes in introductory CS courses. Wu's Castle is a game where students program changes in loops and arrays in an interactive, visual way. The game provides immediate feedback and helps students visualize code execution in a safe environment. We compared the game to a traditional programming assignment in an introductory CS course. In our study, half of the students were randomly selected to play the learning game first and half to write a program first. Our results show that students who play our learning game first outperform those who write a program before playing the game. Students in the game-first group felt they spent less time on the assignments, and all students preferred the learning game over the program. These results suggest that games like Wu's Castle can help prepare students to create deeper, more robust understanding of computing concepts while improving their perceptions of computing homework assignments.
A technological review of the FORTRAN I compiler
Authors: F. E. Allen
Venue: Proceedings of the June 7-10, 1982, national computer conference (1982)

The FORTRAN I compiler functions and organizations are described and shown to form the basis for many of the techniques used in modern compilers.