ppxscal/embedding_network huggingface dataset:
On Integrating Scientific Resources through Semantic Registration
Authors: Shawn Bowers, Kai Lin, Bertram Ludascher
Venue: Proceedings of the 16th International Conference on Scientific and Statistical Database Management (2004)

In many data-centric scientific applications it is common toregister datasets and computational services with a federationregistry (also commonly called a catalog, directory, orrepository). For example, the scientific data-handling systemunder development in the SEEK project must considervarious dataset registries, including: MCAT, for access toSRB-registered datasets [SDSC Storage Resource Broker (SRB)]; Metacat, for KNB-registered datasets [http://knb.ecoinformatics.org/software/metacat/]; DiGIR, for UDDI-registered data [Distributed Generic Information Retrieval (DiGIR)]; and Xanthoria,an XML-based data registry [A distributed query system for XML encoded data]. A challenge for SEEK, and similar efforts such as GEON, is to provideuniform access to registries and registered resources, basedon emerging web and grid standards.Providing uniform access is especially difficult for scientificresources due to their inherent structural and semanticheterogeneity. We focus on the use of ontologies for semanticallyregistering scientific resources, and consider theimplications of semantic registration for enabling uniformregistry-based operations. In general, the use of ontologiesoffers richer contructs and more flexibility for classifying,discovering, and integrating scientific resources when comparedwith typical keyword-based metadata approaches.
The Priority R-tree: a practically efficient and worst-case optimal R-tree
Authors: Lars Arge, Mark de Berg, Herman J. Haverkort, Ke Yi
Venue: Proceedings of the 2004 ACM SIGMOD international conference on Management of data (2004)

We present the Priority R-tree, or PR-tree, which is the first R-tree variant that always answers a window query using O((N/B)1 1/d + T/B) I/Os, where N is the number of d-dimensional (hyper-) rectangles stored in the R-tree, B is the disk block size, and T is the output size. This is provably asymptotically optimal and significantly better than other R-tree variants, where a query may visit all N/B leaves in the tree even when T = 0. We also present an extensive experimental study of the practical performance of the PR-tree using both real-life and synthetic data. This study shows that the PR-tree performs similar to the best known R-tree variants on real-life and relatively nicely distributed data, but outperforms them significantly on more extreme data.
A Virtual Environment Tool Applied to Visualize Construction Processes
Venue: Proceedings of the Theory and Practice of Computer Graphics 2004 (TPCG'04) (2004)

This communication describes a Virtual Realitytechnology application in the construction-trainingdomain. A prototype was developed that serves as adidactic tool for civil engineering students ofdisciplines concerned with building construction.Geometric Modeling and Virtual Reality techniquesare used on the visual simulation of constructionprocesses and to define user-friendly interfaces inorder to access construction information, which couldprove useful to civil engineering professionals.The construction of a double brick wall is the casestudied. The wall is defined as a three-dimensionalgeometric model formed with the several componentsneeded to construct it. Using the wallýs virtual model itis possible to show, in an interactive way, the sequenceof the construction process and observe, from anypoint of view, the configurations in detail of thebuilding components. This is a didactic application inthe construction processes domain of great interest tocivil engineering students.
Little red plane
Venue: ACM SIGGRAPH 2003 video review on Animation theater program: part 2 - Volume 146 (2003)

In a tree house, safe from the world around him, a little boy immerses himself in dreams of flying. Soon, his imagination takes him on a spiritual journey with a gift from his father. This flight fantasy transports him to an astonishing world where he is given opportunity to reconcile the past. Copyright held by creator.
Universities Focus on Pervasive Computing Research
Authors: Terry Costlow
Venue: IEEE Distributed Systems Online (2004)

The Cambridge-MIT Institute is focusing its research efforts on pervasive computing challenges, including security, networking, and user interfaces.
The Experience of the Empty Museum. Displaying Cultural Contents on an Immersive, Walkable VR Room
Authors: Luis Hernandez, Javier Taibo, Antonio Seoane, Ruben Lopez, Rocio Lopez
Venue: Proceedings of the Computer Graphics International (2004)

This paper describes the use of an immersive, walkable VR system called The Empty Museum that the authors have developed to allow the users to walk in virtual spaces where they can experience interactive 3D cultural contents. The paper briefly describes the architecture of the system, to focus on the analysis of the modes of interaction between user and content in this hybrid space where the user itself takes the role of the cursor and the physical space constitutes the interface. Finally, it shows several examples of its use on a real exhibition to display contents related to local topics, from traditions to Art.
Anonymizing Web Services through a Club Mechanism with Economic Incentives
Authors: Mamata Jenamani, Leszek Lilien, Bharat Bhargava
Venue: Proceedings of the IEEE International Conference on Web Services (2004)

Preserving privacy during Web transactions is amajor concern for individuals and organizations. One ofthe solutions proposed in the literature is to maintain anonymitythrough group cooperation during Web transactions.The lack of understanding of incentives for encouraginggroup cooperation is a major drawback in such systems.We propose an anonymizing club mechanism, andsequential economic strategy for trusted collaboration. Wemodel the individual transactions as a Prisoners' Dilemma,where two players either cooperate or defect whilemaintaining each other's anonymity. The activities of theparticipants over a series of transactions can be modeledas a sequential repeated game. We determine conditions toensure cooperation among the participants in the sequentialrepeated game, even if defecting is a dominant strategyin each individual Prisoners' Dilemma game. Our resultsshow that by adopting an appropriate initiation fee andadequate fine for malicious behavior, both enforcedthrough a trusted central authority, we can sustain cooperationin the proposed anonymizing club mechanism.
The effect of faults on network expansion
Authors: Amitabha Bagchi, Ankur Bhargava, Amitabh Chaudhary, David Eppstein, Christian Scheideler
Venue: Proceedings of the sixteenth annual ACM symposium on Parallelism in algorithms and architectures (2004)

In this paper we study the problem of how resilient networks are to node faults. Specifically, we investigate the question of how many faults a network can sustain so that it still contains a large (i.e. linear-sized) connected component that still has approximately the same expansion as the original fault-free network. For this we apply a pruning technique which culls away parts of the faulty network which have poor expansion. This technique can be applied to both adversarial faults and to random faults. For adversarial faults we prove that for every network with expansion α, a large connected component with basically the same expansion as the original network exists for up to a constant times α • n faults. This result is tight in the sense that every graph G of size n and uniform expansion α (•),i.e. G has an expansion of α (n) and every subgraph G' of size m of G has an expansion of O (α (m)), can be broken into sublinear components with w(α (n) • n) faults.For random faults we observe that the situation is significantly different. In this case the expansion of a graph only gives a very weak bound on its resilience to random faults. Specifically, there are networks of uniform expansion O(≾n) that are resilient against a constant fault probability but there are also networks of uniform expansion Ω(1/log n) that are not resilient against a O(1/log n) fault probability. Thus, a different parameter is needed. For this we introduce the span of a graph which allows us to determine the maximum fault probability in a much better way than the expansion can. We use the span to show the first known results for the effect of random faults on the expansion of d-dimensional meshes.
Multiple-nozzle ink jet printing experiment
Authors: Richard H. Darling, Chen-Hsiung Lee, Lawrence Kuhn
Venue: IBM Journal of Research and Development (1984)

An experimental printer is described which utilizes a densely packed array of ink jets operated in a binary, pressurized, asynchronous mode. The printer configuration, the ink jet head structure, the operating point, and the maintenance approach are all discussed.
Shell Creation, Representation and Visualization from an Arbitrary f(x,y,z)=0 Polynomial Shape Description
Venue: Proceedings of the Theory and Practice of Computer Graphics 2004 (TPCG'04) (2004)

This paper demonstrates a software and hardware implementation for creating and visualizing a three dimensional voxel based model for any arbitrary polynomial function.Preliminary results demonstrate its use from the model creation, within a cluster computing engine, to a large real-time visualization system via a small PC rendering farm, have been carried out. This includes the choice of data representation and transmission across a university campus. A fully automated and on-demand model modification process is required in the next phase of implementation, as well as improvements in each of the stages of computation, translation, visualization and human interaction.
A finite branch-and-bound algorithm for two-stage stochastic integer programs
Authors: Shabbir Ahmed, Mohit Tawarmalani, Nikolaos V. Sahinidis
Venue: Mathematical Programming: Series A and B (2004)

This paper addresses a general class of two-stage stochastic programs with integer recourse and discrete distributions. We exploit the structure of the value function of the second-stage integer problem to develop a novel global optimization algorithm. The proposed scheme departs from those in the current literature in that it avoids explicit enumeration of the search space while guaranteeing finite termination. Computational experiments on standard test problems indicate superior performance of the proposed algorithm in comparison to those in the existing literature.
On coresets for k-means and k-median clustering
Authors: Sariel Har-Peled, Soham Mazumdar
Venue: Proceedings of the thirty-sixth annual ACM symposium on Theory of computing (2004)

In this paper, we show the existence of small coresets for the problems of computing k-median and k-means clustering for points in low dimension. In other words, we show that given a point set P in Rd, one can compute a weighted set S ⊆ P, of size O(k ε-d log n), such that one can compute the k-median/means clustering on S instead of on P, and get an (1+ε)-approximation. As a result, we improve the fastest known algorithms for (1+ε)-approximate k-means and k-median. Our algorithms have linear running time for a fixed k and ε. In addition, we can maintain the (1+ε)-approximate k-median or k-means clustering of a stream when points are being only inserted, using polylogarithmic space and update time.
An ontology of randomized controlled trials for evidence-based practice: content specification and evaluation using the competency decomposition method
Authors: Ida Sim, Ben Olasov, Simona Carini
Venue: Journal of Biomedical Informatics (2004)

Randomized controlled trials (RCTs) are one of the least biased sources of clinical research evidence, and are therefore a critical resource for the practice of evidence-based medicine. With over 10,000 new RCTs indexed in Medline each year, knowledge systems are needed to help clinicians translate evidence into practice. Common ontologies for RCTs and other domains would facilitate the development of these knowledge systems. However, no standard method exists for developing domain ontologies. In this paper, we describe a new systematic approach to specifying and evaluating the conceptual content of ontologies. In this method, called competency decomposition, the target task for an ontology is hierarchically decomposed into subtasks and methods, and the ontology content is specified by identifying the domain information required to complete each of the subtasks. We illustrate the use of this competency decomposition approach for the content specification and evaluation of an RCT ontology for evidence-based practice.
Development of Flexible Peer-To-Peer Information Systems Using Adaptable Mobile Agents
Authors: Jean-Paul Arcangeli, Sebastien Leriche, Marc Pantel
Venue: Proceedings of the Database and Expert Systems Applications, 15th International Workshop (2004)

Wide-area networks provide an easy access to many different distributed and heterogeneous data sources. The development of automated operating tools is still complex, particularly because of evolution and adaptation requirements (to the data sources structures and to the network Quality of Service). The purpose of this paper is to evaluate the advantages of adaptable mobile agents in order to simplify the development and the deployment. As an experiment, we develop a prototype of peer-to-peer information system, and we show how agent mobility and adaptation abilities help in implementing various forms of adaptation: adaptation to the execution context, access to new servers with initially unknown communication protocols, dynamic modification of search algorithms based on results provided by the servers. Then, we show how these techniques can be easily extended to other problems such as search and upgrade of software components.
Fast algorithms for fair dynamic load redistribution in heterogeneous environments
Authors: Tiberiu Rotaru, Hans-Heinrich Nägeli
Venue: Applied Numerical Mathematics (2004)

Efficiently running parallel applications on distributed computing environments requires adequate fair dynamic load redistribution techniques. In this paper, two fast algorithms for maintaining the fairness in a dynamic heterogeneous context are discussed. The first algorithm is based upon a conjugate gradient method and solves a quadratic optimization problem. The second algorithm finds the solution of the same problem using the characteristic polynomial of the generalized Laplacian of the communication graph. Both algorithms are faster than the well-known diffusion algorithms. Experimental results are reported.
A hybrid hardware-accelerated algorithm for high quality rendering of visual hulls
Authors: Ming Li, Marcus Magnor, Hans-Peter Seidel
Venue: Proceedings of Graphics Interface 2004 (2004)

In this paper, a novel hybrid algorithm is presented for the fast construction and high-quality rendering of visual hulls. We combine the strengths of two complementary hardware-accelerated approaches: direct constructive solid geometry (CSG) rendering and texture mapping-based visual cone trimming. The former approach completely eliminates the aliasing artifacts inherent in the latter, whereas the rapid speed of the latter approach compensates for the performance deficiency of the former. Additionally, a new view-dependent texture mapping method is proposed. This method makes efficient use of graphics hardware to perform per-fragment blending weight computation, which yields better rendering quality. Our rendering algorithm is integrated in a distributed system that is capable of acquiring synchronized video streams and rendering visual hulls in real time or at interactive frame rates from up to eight reference views.
Introduction from Session Chair: Component Models for Dependable Systems
Authors: M. R. V. Chaudron, J. Muskens
Venue: Proceedings of the 30th EUROMICRO Conference (2004)

This session introduces 8 papers in the area of component models for depenable systems. These papers are grouped into 3 themes.
A Post-Optimality Analysis Algorithm for Multi-Objective Optimization
Authors: Vandana Venkat, Sheldon H. Jacobson, James A. Stori
Venue: Computational Optimization and Applications (2004)

Algorithms for multi-objective optimization problems are designed to generate a single Pareto optimum (non-dominated solution) or a set of Pareto optima that reflect the preferences of the decision-maker. If a set of Pareto optima are generated, then it is useful for the decision-maker to be able to obtain a small set of preferred Pareto optima using an unbiased technique of filtering solutions. This suggests the need for an efficient selection procedure to identify such a preferred subset that reflects the preferences of the decision-maker with respect to the objective functions. Selection procedures typically use a value function or a scalarizing function to express preferences among objective functions. This paper introduces and analyzes the Greedy Reduction (GR) algorithm for obtaining subsets of Pareto optima from large solution sets in multi-objective optimization. Selection of these subsets is based on maximizing a scalarizing function of the vector of percentile ordinal rankings of the Pareto optima within the larger set. A proof of optimality of the GR algorithm that relies on the non-dominated property of the vector of percentile ordinal rankings is provided. The GR algorithm executes in linear time in the worst case. The GR algorithm is illustrated on sets of Pareto optima obtained from five interactive methods for multi-objective optimization and three non-linear multi-objective test problems. These results suggest that the GR algorithm provides an efficient way to identify subsets of preferred Pareto optima from larger sets.
Bjork "Nature is Ancient"
Authors: Jay Lichtman
Venue: ACM SIGGRAPH 2003 video review on Electronic theater program on Electronic theater program - Volume 144 (2003)

The piece features intricate Adam and Eve creatures that have an abstract, primitive form and live in a fluid environment alive with microscopic life. Using NURBS modeling, Glassworks' 3D department created layers of texturing to achieve the complex look of the characters. The membrane layers were achieved via a plug-in shader which essentially creates millions of soft particles that build up without all the hard edges of typical 3D geometry. Completed using Maya and Inferno with the shader programmed in C++. Copyright held by creator. 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
An optimizing compiler for batches of temporal logic formulas
Authors: James Ezick
Venue: ACM SIGSOFT Software Engineering Notes (2004)

Model checking based on validating temporal logic formulas has proven practical and effective for numerous software engineering applications. As systems based on this approach have become more mainstream, a need has arisen to deal effectively with large batches of formulas over a common model. Presently, most systems validate formulas one at a time, with little or no interaction between validation of separate formulas. This is the case despite the fact that, for a wide range of applications, a certain level of redundancy between domain-related formulas can be anticipated.This paper presents an optimizing compiler for batches of temporal logic formulas. A component of the Carnauba model checking system, this compiler addresses the need to handle batches of temporal logic formulas by leveraging the framework common to optimizing programming language compilers. Just as traditional optimizing compilers attempt to exploit redundancy and other solvable properties in a program to reduce the demand on a runtime system, this compiler exploits similar properties in groups of formulas to reduce the demand on a model checking engine. Optimizations are performed via a set of distinct, interchangeable optimization passes operating on a common intermediate representation. The intermediate representation captures the full modal mu-calculus, and the optimization techniques are applicable to any temporal logic subsumed by that logic. The compiler offers a unified framework for expressing some well understood single-formula optimizations as well as numerous inter-formula optimizations that capitalize on redundancy, logical implication, and, optionally, model-specific knowledge. It is capable of working either in place of, or as a preprocessor for, other optimization algorithms. The result is a system that, when applied to a potentially heterogeneous collection of formulas over a common problem domain, is able to measurably reduce the time and space requirements of the subsequent model checking engine.
Partition Theorems for Left and Right Variable Words
Authors: Neil Hindman, Randall McCutcheon
Venue: Combinatorica (2004)

In 1984 T. Carlson and S. Simpson established an infinitary extension of the Hales&#x2013;Jewett Theorem in which the leftmost letters of all but one of the words were required to be variables. (We call such words left variable words.) In this paper we extend the Carlson&#x2013;Simpson result for left variable words, prove a corresponding result about right variable words, and determine precisely the extent to which left and right variable words can be combined in such extensions. The results mentioned so far all involve a finite alphabet. We show that the results for left variable words do not extend to words over an infinite alphabet, but that the results for right variable words do extend.
A Decentralized Treatment of a Highly Distributed Chinese-Wall Policy
Venue: Proceedings of the Fifth IEEE International Workshop on Policies for Distributed Systems and Networks (2004)

Access control (AC) technology has come a longway from its roots as the means for sharing resourcesbetween processes running on a single machine,to a mechanism for regulating the interactionamong agents (software components, and people)distributed throughout the internet. But despite thedistributed nature of the systems being regulated,the conventional enforcement mechanism for ACpolicies remains basically centralized, where a single(although possibly replicated) reference monitor(RM) is used to mediate the interaction betweenmembers of a given community of agents, accordingto a given policy. This papers demonstrates oneof the main drawbacks of centralized AC mechanisms,when applied to distributed systems, and toshows the absence of this drawback under the inherentlydecentralized law-governed interaction (LGI)mechanism.
Flow classification by histograms: or how to go on safari in the internet
Authors: Augustin Soule, Kavé Salamatia, Nina Taft, Richard Emilion, Konstantina Papagiannaki
Venue: Proceedings of the joint international conference on Measurement and modeling of computer systems (2004)

In order to control and manage highly aggregated Internet traffic flows efficiently, we need to be able to categorize flows into distinct classes and to be knowledgeable about the different behavior of flows belonging to these classes. In this paper we consider the problem of classifying BGP level prefix flows into a small set of homogeneous classes. We argue that using the entire distributional properties of flows can have significant benefits in terms of quality in the derived classification. We propose a method based on modeling flow histograms using Dirichlet Mixture Processes for random distributions. We present an inference procedure based on the Simulated Annealing Expectation Maximization algorithm that estimates all the model parameters as well as flow membership probabilities - the probability that a flow belongs to any given class. One of our key contributions is a new method for Internet flow classification. We show that our method is powerful in that it is capable of examining macroscopic flows while simultaneously making fine distinctions between different traffic classes. We demonstrate that our scheme can address issues with flows being close to class boundaries and the inherent dynamic behaviour of Internet flows.