ppxscal/embedding_network huggingface dataset:
A Stereo Matching Algorithm with an Adaptive Window: Theory and Experiment
Authors: T. Kanade, M. Okutomi
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

A central problem in stereo matching by computing correlation or sum of squared differences (SSD) lies in selecting an appropriate window size. The window size must be large enough to include enough intensity variation for reliable matching, but small enough to avoid the effects of projective distortion. If the window is too small and does not cover enough intensity variation, it gives a poor disparity estimate, because the signal (intensity variation) to noise ratio is low. If, on the other hand, the window is too large and covers a region in which the depth of scene points (i.e., disparity) varies, then the position of maximum correlation or minimum SSD may not represent correct matching due to different projective distortions in the left and right images. For this reason, a window size must be selected adaptively depending on local variations of intensity and disparity. The authors present a method to select an appropriate window by evaluating the local variation of the intensity and the disparity. The authors employ a statistical model of the disparity distribution within the window. This modeling enables the authors to assess how disparity variation, as well as intensity variation, within a window affects the uncertainty of disparity estimate at the center point of the window. As a result, the authors devise a method which searches for a window that produces the estimate of disparity with the least uncertainty for each pixel of an image: the method controls not only the size but also the shape (rectangle) of the window. The authors have embedded this adaptive-window method in an iterative stereo matching algorithm: starting with an initial estimate of the disparity map, the algorithm iteratively updates the disparity estimate for each point by choosing the size and shape of a window till it converges. The stereo matching algorithm has been tested on both synthetic and real images, and the quality of the disparity maps obtained demonstrates the effectiveness of the adaptive window method.
Differential Relational Calculus for Integrity Maintenance
Authors: Levent V. Orman
Venue: IEEE Transactions on Knowledge and Data Engineering (1998)

A differential calculus for first-order logic is developed to enforce database integrity. Formal differentiation of first-order sentences is useful in maintaining database integrity, since once a database constraint is expressed as a first-order sentence, its derivative with respect to a transaction provides the necessary and sufficient condition for maintaining integrity. The derivative is often much simpler to test than the original constraint since it maintains integrity differentially by assuming integrity before the transaction, and testing only for new violations. The formal differentiation requires no resolution search, but only substitution. It is more efficient than resolution-based approaches; and it provides a considerably more general solution than previous substitution-based methods since it is valid for all first-order sentences and with all transactions involving arbitrary collections of atomic changes to the database. It also produces a large number of sufficient conditions that are often less strict than those of the previous approaches; and it can be extended to accommodate many dynamic constraints.
Boosting System Performance with Optimistic Distributed Protocols
Authors: Fernando Pedone
Venue: Computer (2001)

Optimistic distributed protocols can dramatically improve system performance if the underlying system assumptions are sound and carry a high degree of probability. Optimistic protocols aggressively execute actions based on best-case system assumptions. Using optimistic protocols unquestionably involves tradeoffs, but if a protocol is well designed and the optimistic assumptions hold frequently enough, the gain in performance outweighs the overhead of repairing actions that execute incorrectly. Demand for high performance under special circumstances in distributed settings has led to the development of optimistic distributed protocols in recent years. Indeed, given the right optimistic assumptions and mechanisms, optimistic protocols can significantly boost the efficiency of a system. Designing such protocols, however, is still a complicated and poorly understood activity. Part of this complexity is due to the inherent complications of distributed protocols and part is due to the lack of knowledge about how optimistic protocols should work. By providing a framework to reason about these protocols, this article is a first step toward systematizing the construction of optimistic distributed protocols. However, much still remains to be understood about how to design their underlying mechanisms.
Streaming Technology in 3G Mobile Communication Systems
Authors: Ingo Elsen, Frank Hartung, Uwe Horn, Markus Kampmann, Liliane Peters
Venue: Computer (2001)

Currently, three incompatible proprietary solutions¿offered by RealNetworks, Microsoft, and Apple¿dominate the Internet streaming software market. In the near future, third-generation mobile communication systems will extend the scope of today's Internet streaming solutions by introducing standardized streaming services that target the mobile user's specific needs.3G systems will provide high-quality streamed Internet content to the rapidly growing mobile market. These systems will offer value-added applications as well, supported by an underlying network that combines streaming services with a range of unique mobile-specific services.Mobile-application scenarios present many challenges, such as how to provide spectrum-efficient streaming services over varied radio-access networks to different types of end-user terminals. The authors assert that their standards-based Interactive Media platform¿recently tested in several field trials¿addresses these challenges by using an architecture that fits seamlessly into 3G mobile-communication systems. An integral part of this architecture is a streaming proxy, which acts on both the service and transport levels.
A Cluster-Based Active Router Architecture
Authors: Girish Welling, Maximilian Ott, Saurabh Mathur
Venue: IEEE Micro (2001)

The Clara prototype architecture collocates routing and computational functionality within a network, providing a scalable, high-performance computing switch router for computational services. Multiple off-the-shelf PCs provide Clara with computational power to, for example, perform real-time transcoding of video with minimal overhead.
An Architecture for Survivable Coordination in Large Distributed Systems
Authors: Dahlia Malkhi, Michael K. Reiter
Venue: IEEE Transactions on Knowledge and Data Engineering (2000)

Coordination among processes in a distributed system can be rendered very complex in a large-scale system where messages may be delayed or lost and when processes may participate only transiently or behave arbitrarily, e.g., after suffering a security breach. In this paper, we propose a scalable architecture to support coordination in such extreme conditions. Our architecture consists of a collection of persistent data servers that implement simple shared data abstractions for clients, without trusting the clients or even the servers themselves. We show that, by interacting with these untrusted servers, clients can solve distributed consensus, a powerful and fundamental coordination primitive. Our architecture is very practical and we describe the implementation of its main components in a system called Fleet.
A generalized &#x03B1;-cut
Authors: Slavka Bodjanova
Venue: Fuzzy Sets and Systems (2002)

For a fixed value α ∈ (0, 1), we introduce the relation α-sharpness and a measure of α-fuzziness of fuzzy sets. Then we propose an approximation of a fuzzy set A by its generalized α-cut Gα(A). A generalized α-cut of A is a special type of fuzzy set that is α-sharper than A and less α-sharp than the crisp approximation of A by its ordinary α-cut Aα. Attention will be given to the generalized α-cuts of fuzzy numbers.
The Design and Implementation of the Ariel Active Database Rule System
Authors: Eric N. Hanson
Venue: IEEE Transactions on Knowledge and Data Engineering (1996)

This paper describes the design and implementation of the Ariel DBMS and its tightly-coupled forward-chaining rule system. The query language of Ariel is a subset of POSTQUEL, extended with a new production-rule sublanguage. Ariel supports traditional relational database query and update operations efficiently, using a System R-like query processing strategy. In addition, the Ariel rule system is tightly coupled with query and update processing. Ariel rules can have conditions based on a mix of selections, joins, events, and transitions. For testing rule conditions, Ariel makes use of a discrimination network composed of a special data structure for testing single-relation selection conditions efficiently, and a modified version of the TREAT algorithm, called A-TREAT, for testing join conditions. The key modification to TREAT (which could also be used in the Rete algorithm) is the use of virtual¿-memory nodes which save storage since they contain only the predicate associated with the memory node instead of copies of data matching the predicate. In addition, the notions of tokens and ¿-memory nodes are generalized to support event and transition conditions. The rule-action executor in Ariel binds the data matching a rule's condition to the action of the rule at rule fire time, and executes the rule action using the query processor.
Executing Algorithms with Hypercube Topology on Torus Multicomputers
Authors: Antonio González, Miguel Valero-García, Luis Díaz de Cerio
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

Many parallel algorithms use hypercubes as the communication topology among their processes. When such algorithms are executed on hypercube multicomputers the communication cost is kept minimum since processes can be allocated to processors in such a way that only communication between neighbor processors is required. However, the scalability of hypercube multicomputers is constrained by the fact that the interconnection cost-per-node increases with the total number of nodes. From scalability point of view, meshes and toruses are more interesting classes of interconnection topologies. This paper focuses on the execution of algorithms with hypercube communication topology on multicomputers with mesh or torus interconnection topologies. The proposed approach is based on looking at different embeddings of hypercube graphs onto mesh or torus graphs. The paper concentrates on toruses since an already known embedding, which is called standard embedding, is optimal for meshes. In this paper, an embedding of hypercubes onto toruses of any given dimension is proposed. This novel embedding is called xor embedding. The paper presents a set of performance figures for both the standard and the xor embeddings and shows that the latter outperforms the former for any torus. In addition, it is proven that for a one-dimensional torus (a ring) the xor embedding is optimal in the sense that it minimizes the execution time of a class of parallel algorithms with hypercube topology. This class of algorithms is frequently found in real applications, such as FFT and some class of sorting algorithms.
The patterns of permutations
Authors: Herbert S. Wilf
Venue: Discrete Mathematics (2002)

Let n,k be positive integers, with k ≤ n, and let τ be a fixed permutation of {1,...,k}. We will call τ the pattern. We will look for the pattern τ in permutations σ of n letters. A pattern τ is said to occur in a permutation σ if there are integers 1 ≤ i1 > i2 > ... > ik ≤ n such that for all 1 ≤ r > s ≤ k we have τ(r) > τ(s) if and only if σ(ir) > σ(is).Example. Suppose τ = (132). Then this pattern of k = 3 letters occurs several times in the following permutation σ, of n = 14 letters (one such occurrence is underlined): σ=(5 2 9 4 14 10 1 3 6 15 8 11 7 13 12).
Surgical simulator for hysteroscopy: a case study of visualization in surgical training
Authors: Kevin Montgomery, LeRoy Heinrichs, Cynthia Bruyns, Simon Wildermuth, Christopher Hasser, Stephanie Ozenne, David Bailey
Venue: Proceedings of the conference on Visualization '01 (2001)

Computer-based surgical simulation promises to provide a broader scope of clinical training through the introduction of anatomic variation, simulation of untoward events, and collection of performance data. We present a haptically-enabled surgical simulator for the most common techniques in diagnostic and operative hysteroscopy- cervical dilation, endometrial resection and ablation, and lesion excision. Engineering tradeoffs in developing a real-time, haptic-rate simulator are discussed.
Minimizing FPGA Interconnect Delays
Authors: Stephen Brown, Muhammad Khellah, Zvonko Vranesic
Venue: IEEE Design Test (1996)

This original study concerns one important aspect of FPGA architecture: the design of its interconnect structure. Early SRAM-based FPGAs featured routing channels that consisted mostly of short wire segments. Joining two or more segments via routing switches formed longer segments. Long connections passing through several switches in series, however, produce a large delay. This occurs because pass-transistor switches have significant series resistance and parasitic capacitance. More recent SRAM-based products include wire segments of various lengths, but no previous study has investigated the trade-offs in selecting a particular routing architecture scheme. Since the wire segment lengths available in an FPGA are key to speed performance, this is the central theme of the research reported here.
Ontologies are not the Panacea in Data Integration: A FlexibleCoordinator to Mediate Context Construction
Authors: Aris M. Ouksel, Iqbal Ahmed
Venue: Distributed and Parallel Databases (1999)

Shared ontologies describe concepts and relationships to resolve semantic conflicts amongst users accessing multiple autonomous and heterogeneous information sources. We contend that while ontologies are useful in semantic reconciliation, they do not guarantee correct classification of semantic conflicts, nor do they provide the capability to handle evolving semantics or a mechanism to support a dynamic reconciliation process. Their limitations are illustrated through a conceptual analysis of several prominent examples used in heterogeneous database systems and in natural language processing. We view semantic reconciliation as a nonmonotonic query-dependent process that requires flexible interpretation of query context, and as a mechanism to coordinate knowledge elicitation while constructing the query context. We propose a system that is based on these characteristics, namely the SCOPES (Semantic Coordinator Over Parallel Exploration Spaces) system. SCOPES takes advantage of ontologies to constrain exploration of a remote database during the incremental discovery and refinement of the context within which a query can be answered. It uses an Assumption-based Truth Maintenance System (ATMS) to manage the multiple plausible contexts which coexist while the semantic reconciliation process is unfolding, and the Dempster-Shafer (DS) theory of belief to model the likelihood of these plausible contexts.
MANAGING A Y2K PROJECT-STARTING NOW
Authors: James E. Schultz
Venue: IEEE Software (1998)

Addressing Y2K problems at this late date requires expedient solutions. Information systems professionals therefore need a practical work plan to assess and correct programmatic problems arising from the use of two-digit years in existing applications programs. The author offers advice on a wide range of solutions, from in-house assessment and recoding to automated tools to outsourcing, and lists resources for those seeking Y2K information, tips, tools, or solution providers.
A polynomial time algorithm for determining zero Euler---Petrie genus of an Eulerian graph
Authors: Brigitte Servatius, Herman Servatius
Venue: Discrete Mathematics (2002)

A dual-Eulerian graph is a plane graph which has an ordering defined on its edge set which forms simultaneously an Euler circuit in the graph and an Euler circuit in the dual graph. Dual-Eulerian graphs were defined and studied in the context of silicon optimization of cmos layouts. They are necessarily of low connectivity, hence may have many planar embeddings. We give a polynomial time algorithm to answer the question whether or not a planar multigraph admits an embedding which is dual-Eulerian and construct such an embedding, if it exists.
Vehicle-Type Motion Estimation From Multi-Frame Images
Authors: Y. Liu, T. S. Huang
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1993)

A model for vehicle-type motion, which assumes that the motion is a rotation around an axis through the vehicle center followed by a forward translation along the main axis of the vehicle, is proposed. When the rotation and the amplitude of translation are constant, this type of motion is shown to be equivalent to a constant camera-centered motion. This indicates that a constant motion in the conventional camera-centered model, which is commonly considered to be artificial, can in fact be a reasonable model in real life. It is shown that a constant vehicle-type motion can be interpreted as a constant screw motion. A linear algorithm for estimating constant vehicle-type motion is presented, and experiments using real scene images are included. As an extension, vehicle-type motion with constant rotation and constantly accelerated translation is discussed.
Reaching Approximate Agreement with Mixed-Mode Faults
Authors: R. M. Kieckhafer, M. H. Azadmanesh
Venue: IEEE Transactions on Parallel and Distributed Systems (1994)

In a fault-tolerant distributed system, different non-faulty processes may arrive atdifferent values for a given system parameter. To resolve this disagreement, processesmust exchange and vote upon their respective local values. Faulty processes mayattempt to inhibit agreement by acting in a malicious or "Byzantine" manner. Approximate agreement defines one form of agreement in which the voted values obtained by the non-faulty processes need not be identical. Instead, they need only agree to within a predefined tolerance. Approximate agreement can be achieved by a sequence of convergent voting rounds, in which the range of values held by non-faulty processes isreduced in each round. Historically, each new convergent voting algorithm has beenaccompanied by ad-hoc proofs of its convergence rate and fault-tolerance, using anoverly conservative fault model in which all faults exhibit worst-case Byzantine behavior.This paper presents a general method to quickly determine convergence rate andfault-tolerance for any member of a broad family of convergent voting algorithms. Thismethod is developed under a realistic mixed-mode fault model comprised of asymmetric,symmetric, and benign fault modes. These results are employed to more accuratelyanalyze the properties of several existing voting algorithms, to derive a sub-family ofoptimal mixed-mode voting algorithms, and to quickly determine the properties ofproposed new voting algorithms.
Windows of Vulnerability: A Case Study Analysis
Authors: William A. Arbaugh, William L. Fithen, John McHugh
Venue: Computer (2000)

The authors propose a life-cycle model for system vulnerabilities, applying to three case studies to show how systems remain vulnerable long after security fixes are available. Complex information and communication systems give rise to design, implementation, and management errors, leading to a vulnerability in an information technology product that can allow security policy violations.Using their vulnerability life-cycle model, the authors present a case study analysis of specific computer vulnerabilities. For each case, the authors provide background information about the vulnerability, such as how attackers exploited it and which systems were affected. They tie the case to the life-cycle model by identifying the dates for each state within the model. Finally, they use a histogram of reported intrusions to show the life of the vulnerability and conclude with an analysis specific to the particular vulnerability.
On sets of n-dimensional subspaces of projective spaces intersecting mutually in an (n-2)-dimensional subspace
Authors: Jörg Eisfeld
Venue: Discrete Mathematics (2002)

Let P be a projective space. Let E be a set of n-dimensional subspaces of P such. that any two elements of E intersect exactly in an (n - 2)-dimensional subspace. In this paper we consider sets E of this type. The case n = 3 was considered in an earlier paper (Geom. Dedicate, submitted for publication). In this paper, we consider the case n ≥ 4. We show that in this case there is essentially only one "new" example E.
Maximizing the SDMA Mobile Radio Capacity Increase by DOA Sensitive Channel Allocation
Authors: Christof Farsakh, Josef A. Nossek
Venue: Wireless Personal Communications: An International Journal (1999)

In a cellular mobile radio system an SDMA (Space Division Multiple Access) component can be implemented for the reuse of radio channels physically incorporated by time, frequency or code slots. Since SDMA is based on the spatial separation of different users operating in the same channel, a DOA (Direction of arrival) sensitive channel allocation scheme is essential for maximizing system capacity. In this paper we present the Eigenvector method, a computationally efficient algorithm to do this job. We also present simulation results on the Eigenvector method operating in a typical urban mobile radio cell. The simulated blocking probabilities are then used to predict the capacity increase which can be expected after adding an SDMA component to a conventional mobile radio system.
On the distribution of the number of monotone boolean functions relative to the number of lower units
Authors: A. D. Korshunov, I. Shmulevich
Venue: Discrete Mathematics (2002)

We find asymptotic formulae for the number of monotone Boolean functions of n variables with a most probable number of terms in the minimal disjunctive normal form. It is proven that the distribution of such functions is asymptotically normal if all monotone Boolean functions are equiprobable. The formulae are different depending on whether n is even or odd.
Demonstrating the Scalability of a Molecular Dynamics Application on a Petaflops Computer
Authors: George S. Almasi Călin Caşcaval José G. Castaños Monty Denneau, Wilm Donath, Maria Eleftheriou, Mark Giampapa, Howard Ho, Derek Lieber, José E. Moreira, Dennis Newns, Marc Snir, Henry S. Warren,  Jr.
Venue: International Journal of Parallel Programming (2002)

The IBM Blue Gene/C parallel computer aims to demonstrate the feasibility of a cellular architecture computer with millions of concurrent threads of execution. One of the major challenges in this project is showing that applications can successfully scale to this massive amount of parallelism. In this paper we demonstrate that the simulation of protein folding using classical molecular dynamics falls in this category. Starting from the sequential version of a well known molecular dynamics code, we developed a new parallel implementation that exploited the multiple levels of parallelism present in the Blue Gene/C cellular architecture. We performed both analytical and simulation studies of the behavior of this application when executed on a very large number of threads. As a result, we demonstrate that this class of applications can execute efficiently on a large cellular machine.