ppxscal/embedding_network huggingface dataset:
Camera Self-Calibration from Unknown Planar Structures Enforcing the Multiview Constraints between Collineations
Authors: Ezio Malis, Roberto Cipolla
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2002)

In this paper, we describe an efficient method to impose the constraints existing between the collineations between images which can be computed from a sequence of views of a planar structure. These constraints are usually not taken into account by multiview techniques in order not to increase the computational complexity of the algorithms. However, imposing the constraints is very useful since it allows a reduction of geometric errors in the reprojected features and provides a consistent set of collineations which can be used for several applications such as mosaicing, reconstruction, and self-calibration. In order to show the validity of our approach, this paper focus on self-calibration from unknown planar structures proposing a method exploiting the consistent set of collineations. Our method can deal with an arbitrary number of views and an arbitrary number of planes and varying camera internal parameters. However, for simplicity, this papers will only discuss the case with one plane in several views. The results obtained with synthetic and real data are very accurate and stable even when using only few images.
Query evaluation via tree-decompositions
Authors: Jörg Flum, Markus Frick, Martin Grohe
Venue: Journal of the ACM (JACM) (2002)

A number of efficient methods for evaluating first-order and monadic-second order queries on finite relational structures are based on tree-decompositions of structures or queries. We systematically study these methods.In the first part of the article, we consider arbitrary formulas on tree-like structures. We generalize a theorem of Courcelle [1990] by showing that on structures of bounded tree-width a monadic second-order formula (with free first- and second-order variables) can be evaluated in time linear in the structure size plus the size of the output.In the second part, we study tree-like formulas on arbitrary structures. We generalize the notions of acyclicity and bounded tree-width from conjunctive queries to arbitrary first-order formulas in a straightforward way and analyze the complexity of evaluating formulas of these fragments. Moreover, we show that the acyclic and bounded tree-width fragments have the same expressive power as the well-known guarded fragment and the finite-variable fragments of first-order logic, respectively.
The Software Rush Hour
Authors: Neil C. Olsen
Venue: IEEE Software (1993)

The author states that, in his experience, software engineering most resembles a dynamically overloaded queue or rush-hour traffic jam. A change measurement model that is unique because it puts the development process in the context of the larger business enterprise and partitions work into dynamic tangible activities, separating work demand from work services, is proposed. Because the change-management model is based on the concept of a dynamically overloaded queue, existing mathematical approximations can be used to estimate gross process behavior. Specifically, the author proposes to use fluid-approximation models to mathematically simulate the software process as a dynamically overloaded queue, applying estimation techniques that are normally used to analyze rush-hour traffic delays.
The role of visualization in understanding a complex forest simulation model
Authors: Douglas H. Deutschman, Catherine Devine, Linda A. Buttel
Venue: ACM SIGGRAPH Computer Graphics (2000)

Ecological research is changing as scientists confront the complexities of natural and human-influenced ecosystems. Early ecological research was dominated by the concepts of equilibrium and determinism [30]. Ecosystems were thought to be stable "super-organisms," fine-tuned by thousands of years of mutual adaptation. In such a world, ecosystems can be completely described with static measures of equilibrium population densities. Although this view has been challenged since its inception, it is only in the past 25 years that it has been displaced as the dominant paradigm in ecology. Today, ecologists describe ecosystems as a dynamic collection of individuals responding in different ways to local interactions, broad-scale environmental change and frequent accidents of history [18, 23, 30]. Although the behavior of the ecosystem is partially understandable from population densities, ecosystem dynamics are variable and complex.Ecologists use an increasingly sophisticated toolbox of techniques to characterize these complex dynamics. Field surveys and laboratory experiments measure the responses of individuals under varied conditions. Thus the mean response as well as the variance in response can be estimated. Improved statistical analyses allow ecologists to describe spatial structure, temporal dynamics and complex spatio-temporal patterns. Finally, mathematical models are being developed that can simulate the complex local interactions of thousands of individuals in a dynamic, heterogeneous environment [9, 17, 34].Improvements in computer hardware and software have facilitated this shift toward increasing complexity. Today, ecologists are seldom limited by hardware, and software to acquire, store and analyze data has improved dramatically in the past decade. In addition, computational models of ecological systems are becoming common [14]. Models are tools to express our understanding of mechanisms governing the structure and function of ecological communities [20]. Models can also be used to make predictions, determine the robustness of these predictions, reveal system properties and highlight weaknesses in our knowledge [8, 25]. Complex ecological models have several important drawbacks including the need for huge amounts of input data, propagation of errors and difficulty interpreting the often voluminous model output [10, 11, 13]. As a result, increased model complexity and detail may not lead to increased understanding [10, 16, 22].
Learning Hardware Using Multiple-Valued Logic, Part 1: Introduction and Approach
Authors: Marek Perkowski, David Foote, Qihong Chen, Anas Al-Rabadi, Lech Jozwiak
Venue: IEEE Micro (2002)

The authors propose a learning-hardware approach as a generalization of evolvable hardware. A massively parallel, reconfigurable processor speeds up logic operators performed in learning hardware. The approach uses combinatorial synthesis methods developed within the framework of the logic synthesis in digital-circuit-design automation.
Solution of Multi-Player Linear-Quadratic Alternating-Move Games and ItsApplication to the Timing Pattern of Wage Adjustment
Authors: Sau-Him Paul Lau
Venue: Computational Economics (2002)

In order to analyze a multi-player linear-quadratic alternating-move dynamic game, this paper develops a solution method by making use of the similar structure of this game and a simultaneous-move dynamic game with alternating payoff functions. It then applies the method to investigate whether staggered or synchronized wage adjustment will be preferred when more than two wage setters interact strategically and dynamically. The results suggest that the strategic benefit provided by staggered wage adjustment is robust with respect to the number of sectors in the economy.
An e-Learning Caregiving Program for Prostate Cancer Patients and Family Members
Authors: Janet Reis, Brendan McGinty, Sandi Jones
Venue: Journal of Medical Systems (2003)

e-health interventions have the potential to augment caregiving training for management of chronic disease. Instruction on caregiving functions often key to patients and families' well being is time consuming but not reimbursable in our current health care system. A theoretically defined interactive multimedia program is described which would assess patient and family member's level of preparedness for specific caregiving functions for prostate cancer and provide tailored skill building vignettes on caregiving techniques. Maximizing today's technology, this program is best designed for a hybrid delivery utilizing both web-based resources and a CD-ROM. Feedback from 45 prostate patients and family members from a Midwest cancer center on perceived needs for caregiving training underscores the potential value of a computer supported intervention for some patients and families. Implementation of the software, marketing, and distribution will be guided in part by recent e-health experiences that leave many health professionals appropriately skeptical about the utility of such products.
Statistical characterisation and modelling of SAR images
Authors: Salim Chitroub, Amrane Houacine, Boualem Sansal
Venue: Signal Processing (2002)

Statistical characterisation and modelling of SAR images is of great importance for developing classification algorithms and specialised filters for speckle noise reduction, among other applications. We present here the methods that estimate from the observed data the models that describe their statistical behaviour in a good way. Using the K distribution, the derived models depend on only one parameter whose estimation can be improved by using the bootstrap sampling method coupled with the Monte Carlo technique. An adequate representation of such models in the Pearson system allows physical interpretations. We show also that the K distribution-based models can be deduced through the use of Mellin multiplicative convolution, which has advantage in leading to an easier derivation. To confirm the judicious choice of the K distribution-based models, we provide a comparison with three other models that are often used in the literature.
ANTS: Network Services Without the Red Tape
Authors: David Wetherall, John Guttag, David Tennenhouse
Venue: Computer (1999)

How well distributed computing systems perform depends a great deal on the network services used to move information among their machines. Yet despite this close correspondence, network services have evolved much more slowly than any other part of the distributed system environment. It's not that the networking community lacks innovative ideas: Internet Protocol version 6, Mobile IP, IP Multicast, and Integrated/ Differentiated Services aim to support multimedia applications more effectively and to accommodate more hosts, many of them mobile. Unfortunately, progress in implementing these solutions lags far behind the identified need. The main problem is the way network protocols must change. First, network protocols are the main vehicle for achieving interoperability, so any candidate internetworking protocol has to become a standard. This means possibly years between the time someone identifies a need and the time everyone agrees on how to address it. Once the new protocol has been accepted, more delays occur because it has to be deployed manually and in a way that is compatible with the existing protocols. ANTS, a new approach to deploying network services, bases interoperability on a programmable network model, not on individual networking protocols. The promise is automatic protocol upgrades, which can hasten progress toward a more responsive Internet.
Implementing Design Diversity to Achieve Fault Tolerance
Authors: John P. J. Kelly, Thomas I. McVittie, Wayne I. Yamamoto
Venue: IEEE Software (1991)

The software faults that are particularly significant in a real-time concurrent system are identified, and the use of design diversity to prevent their occurrence is examined. Two approaches to enforced diversity, recovery-block software and multiversion software, are discussed. The recovery-block scheme combines N diverse software versions arranged (conceptually, at least) in sequential order, although the versions may also be organized to execute concurrently. The multiversion-software approach excuses all N versions in parallel, taking advantage of the redundant processors likely to be available in any system that must tolerate hardware and software faults. Although different, both approaches require sufficiently diverse development environments and that faults in the specification do not lead to similar errors.
Square Meshes Are Not Optimal for Convex Hull Computation
Authors: Dharmavani Bhagavathi, Himabindu Gurla, Stephan Olariu, James L. Schwing, Jingyuan Zhang
Venue: IEEE Transactions on Parallel and Distributed Systems (1996)

Recently it has been noticed that for semigroup computations and for selection rectangular meshes with multiple broadcasting yield faster algorithms than their square counterparts. The contribution of this paper is to provide yet another example of a fundamental problem for which this phenomenon occurs. Specifically, we show that the problem of computing the convex hull of a set of n sorted points in the plane can be solved in ${\rm O}(n^{{\textstyle{1 \over 8}}}\, {\rm log}^{{\textstyle{3 \over 4}}}\,n)$ time on a rectangular mesh with multiple broadcasting of size$$n^{{\textstyle{3 \over 8}}}\,{\rm log}^{{\textstyle{1 \over 4}}}\,n\times {\textstyle{{n^{{ \textstyle{5 \over 8}}}} \over {{\rm log}^{{\textstyle{1 \over 4}}}\,n}}}.$$The fastest previously-known algorithms on a square mesh of size $\sqrt n\times \sqrt n$ run in ${\rm O}(n^{{\textstyle{1 \over 6}}})$ time in case the n points are pixels in a binary image, and in ${\rm O}(n^{{\textstyle{1 \over 6}}}\,{\rm log}^{{\textstyle{2 \over 3}}}\,n).$ time for sorted points in the plane.
Collection-Aware Optimum Sequencing of Operations and Closed-Form Solutions for the Distribution of a Divisible Load on Arbitrary Processor Trees
Authors: Gerassimos D. Barlas
Venue: IEEE Transactions on Parallel and Distributed Systems (1998)

The problem of optimally distributing a divisible load to the nodes of an arbitrary processor tree is tackled in this paper. The rigorous mathematical foundation presented allows the derivation of the sequence of operations that is necessary to obtain the minimum processing time, along with closed-form expressions that yield the solution in time O(NP), where P is the number of tree nodes and N their maximum degree. The main contributions of this work are: (1) both load distribution and result collection overheads are considered, thus providing better resource utilization, and (2) arbitrary processor trees are examined in contrast with previous approaches that examined either complete homogeneous trees, or single level trees. Additionally, approximate algorithms for solving the problem of specifying the optimum subset of active processors for a given load, are presented and evaluated.
Ontologies for conceptual modeling: their creation, use, and management
Authors: Vijayan Sugumaran, Veda C. Storey
Venue: Data Knowledge Engineering (2002)

Although ontologies have been proposed as an important and natural means of representing real world knowledge for the development of database designs, most ontology creation is not carried out systematically. To be truly useful, a repository of ontologies, organized by application domain is needed, along with procedures for creating and integrating ontologies into database design methodologies. This research proposes a methodology for creating and managing domain ontologies. An architecture for an ontology management system is presented and implemented in a prototype. Empirical validation of the prototype demonstrates the effectiveness of the research.
Multithreading Programs: Guidelines for DCE Applications
Authors: David E. Ruddock, Balakrishnan Dasarathy
Venue: IEEE Software (1996)

Multithreading provides a popular mechanism for achieving concurrency, but managing that concurrency can daunt even experienced programmers. The authors offer a tutorial on using threads safely and effectively in an RPC-supported, distributed environment.
An edge preserving noise smoothing technique using multiscale morphology
Authors: S. Mukhopadhyay, B. Chanda
Venue: Signal Processing (2002)

This paper presents a method for improving the quality of gray-level images by reducing the effect of noise using multiscale morphology. The underlying concept of the work is to assign progressively less importance to features of smaller scales as their possibilities of being noise particles are more. Features at various scales are extracted by means of morphological filtering. The proposed scheme is first illustrated in one dimension. Morphological towers are built to implement the method in two dimensions. The proposed algorithm has been tested on a set of real images corrupted with different types of noise. The results are compared with those of other standard noise removal algorithms based on some standard performance measures. A modification of the method considering noise statistics along with its results are also presented in this paper.
Addressing and Routing in Hexagonal Networks with Applications for Tracking Mobile Users and Connection Rerouting in Cellular Networks
Authors: Fabian Garcia Nocetti, Ivan Stojmenovic, Jingyuan Zhang
Venue: IEEE Transactions on Parallel and Distributed Systems (2002)

Nodes in a hexagonal network are placed at the vertices of a regular triangular tessellation, so that each node has up to six neighbors. The network is proposed as an alternative interconnection network to mesh connected computer (with nodes serving as processors) and is used also to model cellular networks where nodes are base stations. In this paper, we propose a suitable addressing scheme for nodes (with two variants), derive a formula for distance between nodes, and present a very simple and elegant routing algorithm. This addressing scheme and corresponding routing algorithm for hexagonal interconnection are considerably simpler than previously proposed solutions. We then apply the addressing scheme for solving two problems in cellular networks. With the new scheme, the distance between the new and old cell to which a mobile phone user is connected can be easily determined and coded with three integers, one of them being zero. Further, in order to minimize the wireless cost of tracking mobile users, we propose hexagonal cell identification codes containing three, four, or six bits, respectively, to implement a distance based tracking strategy. These schemes do not have errors in determining cell distance in existing hexagonal based cellular networks, which is not the case with recently proposed 3 bit cell identification codes based on an artificial square mesh placed over a hexagonal network (moreover, the existing mesh schemes fail to address the diagonal moves that may cause additional unrecoverable errors). Our schemes provide efficient implementation of distance and movement based tracking schemes in cellular networks, by providing information generally not available to the user, and means to manipulate it for accurate cell distance determination. Another application is for connection rerouting in cellular networks during a path extension process. In a path extension scheme, the path for ongoing calls is extended from the old base station to a new one using the link between neighboring base stations. If the path is extended several times due to mobility, our scheme provides an elegant way to reroute the connection from the latest base station to the base station of original connection and, therefore, minimize the length of extended path.
Comments on "A Characterization of Binary Decision Diagrams"
Authors: I. Wegener
Venue: IEEE Transactions on Computers (1994)

Chakravarty presents a characterization of BDD's in terms of the complexity of some computational problems. In these comments, some incorrectly stated restrictions on the "number of repeated variables" are corrected and results on the translation problem (to include EXOR and NEXOR gates) are generalized.
Analyzing Data Locality in Numeric Applications
Authors: Jesús Sánchez, Antonio González
Venue: IEEE Micro (2000)

SPLAT provides programmers a fast and accurate study of memory behavior without the necessity of a costly memory simulator. The tool is suitable for use as a step in an iterative optimization process in time-consuming numeric applications.
CAM2: A Highly-Parallel Two-Dimensional Cellular Automaton Architecture
Authors: Takeshi Ikenaga, Takeshi Ogura
Venue: IEEE Transactions on Computers (1998)

Cellular automaton (CA) is a promising computer paradigm that can break through the von Neumann bottleneck. Two-dimensional CA is especially suitable for application to pixel-level image processing. Although various architectures have been proposed for processing two-dimensional CA, there are no compact, practical computers. So, in spite of its great potential, CA is not widely used. This paper proposes a highly-parallel two-dimensional cellular automaton architecture called CAM2 and presents some evaluation results. CAM2 can attain pixel-order parallelism on a single board because it is composed of a CAM, which makes it possible to embed an enormous number processing elements (PEs), corresponding to CA cells, onto one VLSI chip. Multiple-zigzag mapping and dedicated CAM functions enable high-performance CA processing. The performance evaluation results show that 256k CA cells, which correspond to a 512 × 512 picture, can be processed by a CAM2 on a single board using deep submicron process technology. The processing speed is more than 10 billion CA cell updates per second. This means that more than a thousand CA-based image processing operations can be done on a 512 × 512 pixel image at video rates (33 msec). CAM2 will widen the potentiality of CA and make a significant contribution to the development of compact and high-performance systems.
Finding and Labeling the Subject of a Captioned Depictive Natural Photograph
Authors: N. C. Rowe
Venue: IEEE Transactions on Knowledge and Data Engineering (2002)

We address the problem of finding the subject of a photographic image intended to illustrate some physical object or objects (¿depictive¿) and taken by usual optical means without magnification (¿natural¿). This could help in developing digital image libraries since important image properties like subject size and color of a photograph are not usually mentioned in accompanying captions and can help rank the photograph retrievals for a user. We explore an approach that identifies the ¿visual focus¿ of the image and the ¿depicted concepts¿ in a caption and connects them. The visual focus is determined by using eight domain-independent characteristics of regions in the segmented image, and the caption depiction is identified by a set a rules applied to the parsed and interpreted caption. The visual-focus determination also does combinatorial optimization on sets of regions to find the set that best satisfies focus criteria. Experiments on 100 randomly selected image-caption pairs show significant improvement in precision of retrieval over simpler methods, and, particularly, emphasizes the value of segmentation of the image.