ppxscal/embedding_network huggingface dataset:
Painlev&#x00E9; equations: nonlinear special functions
Authors: Peter A. Clarkson
Venue: Journal of Computational and Applied Mathematics (2003)

The six Painlevé equations (PI-PVI) were first discovered about a hundred years ago by Painlevé and his colleagues in an investigation of nonlinear second-order ordinary differential equations. Recently, there has been considerable interest in the Painlevé equations primarily due to the fact that they arise as reductions of the soliton equations which are solvable by inverse scattering. Consequently, the Painlevé equations can be regarded as completely integrable equations and possess solutions which can be expressed in terms of solutions of linear integral equations, despite being nonlinear equations. Although first discovered from strictly mathematical considerations, the Painlevé equations have arisen in a variety of important physical applications including statistical mechanics, plasma physics, nonlinear waves, quantum gravity, quantum field theory, general relativity, nonlinear optics and fibre optics.The Painlevé equations may be thought of a nonlinear analogues of the classical special functions. They possess hierarchies of rational solutions and one-parameter families of solutions expressible in terms of the classical special functions, for special values of the parameters. Further the Painlevé equations admit symmetries under affine Weyl groups which are related to the associated Bäcklund transformations.In this paper, I discuss some of the remarkable properties which the Painlevé equations possess including connection formulae, Bäcklund transformations associated discrete equations, and hierarchies of exact solutions. In particular, the second Painlevé equation PΠ is used to illustrate these properties and some of the applications of PΠ are also discussed.
The cohesive metaschema: a higher-level abstraction of the UMLS semantic network
Authors: Yehoshua Perl, Zong Chen, Michael Halper, James Geller, Li Zhang, Yi Peng
Venue: Journal of Biomedical Informatics (2002)

The Unified Medical Language System (UMLS) joins together a group of established medical terminologies in a unified knowledge representation framework. Two major resources of the UMLS are its Metathesaurus, containing a large number of concepts, and the Semantic Network (SN), containing semantic types and forming an abstraction of the Metathesaurus. However, the SN itself is large and complex and may still be difficult to view and comprehend. Our structural partitioning technique partitions the SN into structurally uniform sets of semantic types based on the distribution of the relationships within the SN. An enhancement of the structural partition results in cohesive, singly rooted sets of semantic types. Each such set is named after its root which represents the common nature of the group. These sets of semantic types are represented by higher-level components called meta-semantic types. A network, called a metaschema, which consists of the meta-semantic types connected by hierarchical and semantic relationships is obtained and provides an abstract view supporting orientation to the SN. The metaschema is utilized to audit the UMLS classifications. We present a set of graphical views of the SN based on the metaschema to help in user orientation to the SN. A study compares the cohesive metaschema to metaschemas derived semantically by UMLS experts.
Length estimation for curves with different samplings
Authors: Lyle Noakes, Ryszard Kozera, Reinhard Klette
Venue: Digital and image geometry: advanced lectures (2001)

This paper* looks at the problem of approximating the length of the unknown parametric curve γ: [0, 1] → Rn from points qi = γ(ti), where the parameters ti are not given. When the ti are uniformly distributed Lagrange interpolation by piecewise polynomials provides efficient length estimates, but in other cases this method can behave very badly [15]. In the present paper we apply this simple algorithm when the ti are sampled in what we call an ε-uniform fashion, where 0 ≤ ε ≤ 1. Convergence of length estimates using Lagrange interpolants is not as rapid as for uniform sampling, but better than for some of the examples of [15]. As a side-issue we also consider the task of approximating γ up to parameterization, and numerical experiments are carried out to investigate sharpness of our theoretical results. The results may be of interest in computer vision, computer graphics, approximation and complexity theory, digital and computational geometry, and digital image analysis.
More about subcolorings
Authors: Hajo Broersma, Fedor V. Fomin, Jaroslav Nešetřil, Gerhard J. Woeginger
Venue: Computing (2002)

A subcoloring is a vertex coloring of a graph in which every color class induces a disjoint union of cliques. We derive a number of results on the combinatorics, the algorithmics, and the complexity of subcolorings.On the negative side, we prove that 2-subcoloring is NP-hard for comparability graphs, and that 3-subcoloring is NP-hard for AT-free graphs and for complements of planar graphs. On the positive side, we derive polynomial time algorithms for 2-subcoloring of complements of planar graphs, and for r-subcoloring of interval and of permutation graphs. Moreover, we prove asymptotically best possible upper bounds on the subchromatic number of interval graphs, chordal graphs, and permutation graphs in terms of the number of vertices.
Decoding Turbo-Like Codes via Linear Programming
Authors: Jon Feldman, David R. Karger
Venue: Proceedings of the 43rd Symposium on Foundations of Computer Science (2002)

We introduce a novel algorithm for decoding turbo-like codes based on linear programming. We prove that for the case of Repeat-Accumulate (RA) codes, under the binary symmetric channel with a certain constant threshold bound on the noise, the error probability of our algorithm is bounded by an inverse polynomial in the code length.Our linear program (LP) minimizes the distance between the received bits and binary variables representing the code bits. Our LP is based on a representation of the code wherecode words are paths through a graph. Consequently, the LP bears a strong resemblance to the min-cost flow LP. The error bounds are based on an analysis of the probability, over the random noise of the channel, that the optimum solution to the LP is the path corresponding to the original transmitted code word.
Structuring and verifying distributed algorithms
Authors: Kaisa Sere, Marina Waldén
Venue: Nordic Journal of Computing (2001)

We present a structuring and verification method for distributed algorithms. The basic idea is that an algorithm to be verified is stepwise transformed into a high level specification through a number of steps, so-called coarsenings. At each step some mechanism of the algorithm is identified, verified and removed while the basic computation of the original algorithm is preserved. The method is based on a program development technique called superposition and it is formalized within the refinement calculus. We will show the usefulness of the method by verifying a complex distributed algorithm for minimum-hop route maintenance due to Chu.
Recursion and corecursion have the same equational logic
Authors: Lawrence S. Moss
Venue: Theoretical Computer Science (2003)

This paper is concerned with the equational logic of definitions whose semantics is given in terms of final coalgebra maps. The framework for our study is iteration theories (cf. e.g. Bloom and Ésik, Iteration Theories: The Equational Logic of Iterative Processes, EATCS Monographs on Theoretical Computer Science, Springer, Berlin, 1993; Theoret. Comput. Sci. 179 (1-2) (1997)), recently re-introduced as models of the FLR0 fragment of the formal language of recursion (Hurkens et al., J. Symbolic Logic 63 (2) (1998) 45; Mos Chovakis, J. Symbolic Logic 54 (1989) 1216; in: M.L. Dalla Chiara et al. (Eds.), Logic and Scientific Methods, Kluwer, Dordrecht, 1997, p. 179). We present a new class of iteration theories derived from final coalgebras. This allows us to reason with a number of types of fixed-point equations which heretofore seemed to require metric or order-theoretic ideas. All of the work can be done using finality properties and equational reasoning. Having a semantics, we obtain the following completeness result: the equations involving fixed-point terms which are valid for final coalgebra interpretations are exactly those valid in a number of contexts pertaining to recursion. For example, they coincide with the equations valid for least-fixed-point recursion on dcpo's. We also present a new version of the proof of the well-known completeness result for iteration theories (see Ésik, Comput. Linguistics Comput. Languages 4 (1982) 95; Hurkens et al., 1998). Our work brings out a connection between coalgebraic reasoning and recursion.
Expert Oracle 9i Database Administration
Authors: Sam R. Alapati, Martin Reid
Venue:  (2003)

:This is the only real Oracle 9i Database Administration book in the market! This 1,000-page book enables a beginner or intermediate level Oracle DBA or Oracle Developer/Manager to master the art of building and managing complex Oracle 9i databases. Expert Oracle 9i Database Administration is thorough in covering all aspects of the 9i database and also includes a UNIX primer as well as an introduction to SQL and PL/SQL. Sam R. Alapati covers the entire spectrum of the new Oracle 9i RDBMS software and clearly explains how to use all of its powerful features.Currently there is no one book that includes the necessary UNIX administration, Windows NT management, and SQL backgrounds and the necessary database administration principles in one book. Sam R. Alapati's book fills that gap well, by providing all the necessary material in one comprehensive volume. Expert Oracle 9i Database Administration is designed as the most complete Oracle 9i database text available today. It takes several courses as well as mastery of several Oracle manuals to become a proficient DBA. A major focus of this book is on the most important features of the Oracle 9i database. Readers will be able to become expert Oracle DBA's by using this book. Sam R. Alapati is an experienced Oracle Database Administration, who holds the Oracle OCP DBA certification and the Hewlett Packard UNIX System Administrator certification. He currently manages Oracle databases at the Boy Scouts of America's National Headquarters in Los Colinas, Texas. Alapati has been dealing with databases for a long time, including the Ingres RDBMS in the mid 1980s. He is also well versed in the Microsoft SQL Server, Sybase, and the IBM DB2 database management systems. Written by an experienced, practicing Certified Oracle DBA The book is actually based on the Oracle 9i version and is not just a revamp of an older book to superficially address the new features of the Oracle 9i database Covers the principles in-depth and also contains a how to section at the end of chapters to help explain how to perform DBA tasks using actual real life commands
Qualitative simulation of temporal concurrent processes using Time Interval Petri Nets
Authors: Vadim Bulitko, David C. Wilkins
Venue: Artificial Intelligence (2003)

This paper presents a formalism called Time Interval Petri Nets (TIPNs), which are designed to support a qualitative simulation of temporal concurrent processes. One of the key features of TIPNs is a uniform use of time intervals throughout the model. This enables a natural and efficient representation of temporal uncertainty in inputs, outputs, and intermediate states of the qualitative simulation. This is required because the exact time of key events, such as the start time of a fire crisis, is typically not known with certainty. Likewise, output conclusions of the qualitative simulation include earliest time and guaranteed time of key events that can be used by a decision maker to select the most appropriate action.Results are described of a TIPN-based qualitative simulator constructed in the domain of ship damage control. The simulator was created to replace an existing quantitative simulator which was too slow to support envisionment-based real-time decision making in this domain. The experimental results showed a speedup of four to five orders of magnitude which enables hyper-real time qualitative prediction of consequences of multiple competing actions. An automated shipboard damage control decision-making system incorporating a TIPN-based qualitative simulator achieved a 318% improvement over human subject matter experts in a large-scale simulated exercise of over 500 scenarios.
Optimistic voting for managing replicated data
Authors: Huaizhong Lin, Chun Chen
Venue: Journal of Computer Science and Technology (2002)

An epidemic model gives an efficient approach for transaction processing of replication systems in weakly connected environments. The approach has the advantages of high adaptation, support for low-bandwidth network, and committing updates in an entirely decentralized control fashion. But the previous implementing protocols, like ROWA protocol, quorum protocol, and voting protocol, have a common shortcoming that they are pessimistic in conflict reconciliation, therefore bring high transaction abort rate and reduce system performance dramatically when the workload scales up. In this paper, an optimistic voting protocol, which introduces condition vote and order vote in the voting process of transactions, is proposed. The condition vote and order vote postpone the final decision on conflicting transactions and avoid transaction aborts that are incurred by read-write and write-write conflicts. Experimental results indicate that the optimistic voting protocol decreases abort rate and improves average response time of transactions markedly when compared to other protocols.
Achieving Environmental and Productivity Improvements Through Model-Based Process Redesign
Authors: Kumar Rajaram, Charles J. Corbett
Venue: Operations Research (2002)

Large-scale industrial production processes face increasingly tight environmental constraints, which can be addressed through costly but relatively simple end-of-pipe solutions, or through cheaper but more subtle pollution prevention approaches. Achieving the process improvements necessary for pollution prevention is challenging due to the inherent complexity and unpredictability of several types of processes found in the food processing, pharmaceuticals, biotechnology, and specialty chemical industries. We propose an iterative procedure to achieve process improvements through model-based process redesign. This procedure is based on successive convex approximations of the process performance model, where product flows and process settings are optimized for a given configuration and the solution and dual variables of this optimization problem are used to update the process configuration following a greedy capacity reallocation procedure. We implemented this procedure over a five-year period at Cerestar, a major European producer of starch products, which led to a dramatic simplification in process configuration. Reduced energy and water consumption led to an estimated $3 million annual cost savings. Moreover, the reduction in environmental impacts allowed Cerestar to maintain current production levels without investing $100 million in additional wastewater treatment capacity to comply with new environmental constraints.
Finite element modeling of non-orthogonal loosely woven fabrics in advanced occupant restraint systems
Authors: Romil R. Tanov, Marlin Brueggert
Venue: Finite Elements in Analysis and Design (2003)

The behavior of loosely woven fabrics differs significantly from other types of woven fabrics. Its unique characteristics have been successfully utilized for the correct operation of some recently developed occupant protection devices for the automotive and heavy machine and truck industry. However, this behavior cannot be efficiently modeled using the currently available material models within a finite element analysis scheme. Therefore, the aim of this work is to present the basics of a formulation of a material model for the analysis of loosely woven fabrics and its implementation in a general-purpose explicit finite element code. To assess the performance of the model, results from the simulation are presented and compared to real test data.
Interface with pre-typing visual feedback for touch-sensitive keyboard
Authors: Roman Ilinski
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

In this paper, a method is described that detects and displays what key a user has touched with his fingertip before the key is pressed. The proposed method is based on the use of a touch-sensitive cover on a pushbutton key set. The identity of the touched key is displayed exactly at the point where the I-beam pointer indicates at the inputting string, so that correct data entry will be made simpler without looking at the keyboard or needing training.
Well-posed variational inequalities
Authors: Muhammad Aslam Noor
Venue: The Korean Journal of Computational Applied Mathematics (2003)

In this paper, we introduce the concept of well-posedness for general variational inequalities and obtain some results under pseudomonotonicity. It is well known that monotonicity implies pseudomonotonicity, but the converse is not true. In this respect, our results represent an improvement and refinement of the previous known results. Since the general variational inequalities include (quasi) variational inequalities and complementarity problems as special cases, results obtained in this paper continue to hold for these problems.
Positive solutions of a nonlinear three-point boundary value problem
Authors: Bing Liu
Venue: Applied Mathematics and Computation (2002)

In this paper, by using Krasnoselskii's fixed point theorem in a cone, we study the existence of single and multiple positive solutions to the three-point boundary value problem (BVP) y"(t) + a(t)f(y(t)) = 0, 0 > t > 1, y'(0) = 0, y(1) = βy(η), where 0 > η > 1, 0 > β > 1. As an application, we also give some examples to demonstrate our results.
An efficient broadcast data clustering method for multipoint queries in wireless information systems
Authors: Yon Dohn Chung, Su Ho Bang, Myoung Ho Kim
Venue: Journal of Systems and Software (2002)

Mobile computing has become a reality with the convergence of two technologies: powerful portable computers and wireless networks. The restrictions of wireless networks, such as bandwidth and energy limitations make data broadcasting an attractive data communication method. This paper addresses the clustering of wireless broadcast data for multipoint queries. By effective clustering of broadcast data, the mobile client can access the data on the air in short latency. In the paper, we define two affinity measures: data affinity and segment affinity. The data affinity is-the degree that two data objects are accessed by queries, and the segment affinity is the degree that two sets of data (i.e., segments) are accessed by queries. Our method clusters data objects based on data and segment affinity measures. We show that the performance of our method is scarcely influenced by the growth of the number of queries.
Schur flow for orthogonal polynomials on the unit circle and its integrable discretization
Authors: Atsushi Mukaihira, Yoshimasa Nakamura
Venue: Journal of Computational and Applied Mathematics (2002)

A one-parameter deformation of the measure of orthogonality for orthogonal polynomials on the unit circle is considered. The corresponding dynamics of the Schur parameters of the orthogonal polynomials is shown to be characterized by the complex semi-discrete modified KdV equation, namely, the Schur flow. A discrete analogue of the Miura transformation is found. An integrable discretization of the Schur flow enables us to compute a Padé approximation of the Carathéodory functions, or equivalently, to compute a Perron-Carathéodory continued fraction in a polynomial time.
Numerical integration error method for zeros of analytic functions
Authors: Toshio Suzuki, Tomohiro Suzuki
Venue: Journal of Computational and Applied Mathematics (2003)

It is shown that a globally convergent zero finding method named the numerical integration error method (NIEM) can be applied to functions in a certain class of analytic functions including exponential type. Some results of numerical experiments are given.
Seamless multi-projector display on curved screens
Authors: Jeroen van Baar, Thomas Willwacher, Srinivas Rao, Ramesh Raskar
Venue: Proceedings of the workshop on Virtual environments 2003 (2003)

We describe a new technique to display seamless images using overlapping projectors on curved surfaces. Our method addresses issues such as automatic registration, smooth intensity blending and efficient rendering. Previous techniques for automatically registered seamless displays have focused mainly on planar displays. Techniques for curved screens currently involve cumbersome manual alignment to make the installation conform to the intended design.
Making Fourier-envelope simulation robust
Authors: Jaijeet Roychowdhury
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Fourier-envelope algorithms are an important component of the mixed-signal/RF verification toolbox. In this paper, we address the unpredictability and lack of robustness that has been reported for these algorithms. We show that the problem stems from fast oscillations in envelopes that are expected to be slowly varying. We demonstrate that this is related to the fact that the envelope equations are always stiff, whether or not the underlying system is. We show that careful choice of envelope initial conditions is necessary to obtain useful solutions, and propose two techniques for finding good initial conditions. Applying these, and solving the envelope equations with stiffly-stable numerical methods, we improve the robustness and reliability of Fourier-envelope methods. We illustrate the new methods with a direct-downconversion mixer circuit.
Optimal Admission Control and Sequencing in a Make-to-Stock/Make-to-Order Production System
Authors: Scott Carr, Izak Duenyas
Venue: Operations Research (2000)

In this paper, we address the problem of admission control and sequencing in a production system that produces two classes of products. The first class of products is made-to-stock, and the firm is contractually obliged to meet demand for this class of products. The second class of products is made-to-order, and the firm has the option to accept (admit) or reject a particular order. The problem is motivated by suppliers in many industries who sign contracts with large manufacturers to supply them with a given product and also can take on additional orders from other sources on a make-to-order basis.We model the joint admission control/sequencing decision in the context of a simple two-classM/ M/1 queue to gain insight into the following problems: 1. How should a firm decide (a) when to accept or reject an additional order, and (b) which type of product to produce next? 2. How should a firm decide what annual quantity of orders to commit to when signing a contract to produce the make-to-stock products?
Incremental construction properties in dimension two: shellability, extendable shellability and vertex decomposability
Authors: Sonoko Moriyama, Fumihiko Takeuchi
Venue: Discrete Mathematics (2003)

We give new examples of shellable, but not extendably shellable two-dimensional simplicial complexes. They include minimal examples that are smaller than those previously known. We also give new examples of shellable, but not vertex decomposable two-dimensional simplicial complexes, including extendably shellable ones. This shows that neither extendable shellability nor vertex decomposability implies the other. We found these examples by enumerating shellable two-dimensional simplicial complexes that are not pseudomanifolds.