ppxscal/embedding_network huggingface dataset:
Building topological maps using minimalistic sensor models
Authors: Maria L. Gini
Venue:  (2003)

This dissertation addresses the problem of simultaneous localization and mapping for miniature robots that have extremely poor odometry and sensing capabilities. Existing robotic mapping algorithms generally assume that the robots have good odometric estimates and have sensors that can return the range or bearing to landmarks in the environment. This work focuses on solutions to this problem for robots where the above assumptions do not hold. A novel method is presented for a sensor poor mobile robot to create a topological estimate of its path through an environment by using the notion of a virtual sensor that equates &ldquo;place signatures&rdquo; with physical locations in space. The method is applicable in the presence of extremely poor odometry and does not require sensors that return spatial (range or bearing) information about the environment. Without sensor updates, the robot's path estimate will degrade due to the odometric errors in its position estimates. When the robot re-visits a location, the geometry of the map can be constrained such that it corrects for the odometric error and better matches the true path. Several maximum likelihood estimators are derived using this virtual sensor methodology. The first estimator uses a physics-inspired mass and spring model to represent the uncertainties in the robot's position and motion. Errors are corrected by relaxing the spring model through numerical simulation to the state of least potential energy. The second method finds the maximum likelihood solution by linearizing a Chi-squared error function. This method has the advantage of explicitly dealing with dependencies between the robot's linear and rotational errors. Finally, the third method employs the iterated form of the Extended Kalman Filter. This method has the advantage of providing a real-time update of the robot's position where the others process all the data at once. Finally, a method is presented for dealing with multiple locations that cannot be disam-biguated because their signatures appear to be identical. In order to decide which sensor readings are associated with what positions in space, the robot's sensor readings and motion history are used to calculate a discrete probability distribution over all possible robot positions.
Finding all essential terms of a characteristic maxpolynomial
Authors: Rainer E. Burkard, Peter Butkovič
Venue: Discrete Applied Mathematics (2003)

Let us denote a ⊕ b = max(a,b) and a ⊗ b = a + b for a, b ∈ oR = R ∪ {-∞} and extend this pair of operations to matrices and vectors in the same way as in linear algebra. We present an O(n2(m + n log n)) algorithm for finding all essential terms of the max-algebraic characteristic polynomial of an n × n matrix over oR with m finite elements. In the cases when all terms are essential, this algorithm also solves the following problem: Given an n × n matrix A and k ∈ {1,...,n}, find a k × k principal submatrix of A whose assignment problem value is maximum.
Satisfiability in semiring constraint satisfaction problems
Authors: Katarina Britz
Venue: Proceedings of the 2003 annual research conference of the South African institute of computer scientists and information technologists on Enablement through technology (2003)

We present the partial satisfiability problem in a semiring constraint satisfaction problem (SCSP) framework. Interpreting the semiring of an SCSP as a lattice of truth values yields a problem in many-valued logic. As in the classical satisfiability problem statement, constraints are formulated as propositions in the logic, using the natural correspondence between semiring operations on the one hand, and connectives in the logic on the other. Partial satisfiability is defined as a binary function which assigns to each constraint in the logic a semiring value in each state, indicating the degree of satisfaction of the constraint in the given state.
A General Stochastic Model for Dynamic Locking in Database Systems
Authors: Yong Jiang, Jie Li, Shoichi Nishimura
Venue: IEEE Transactions on Computers (2004)

Abstract--In this paper, we present a novel stochastic model to study the performances of the two-phase dynamic locking in database systems with no-waiting policy. It is a general stochastic model to describe the database environment and transaction states in detail. It deals with the nonuniform access, write-locking, read-locking, and multiple transaction classes in a unique way. In the analysis, we first solve the steady-state probability of the system. Then, we give the mean number of transactions with k locks, the mean total number of locks held by all transactions, the mean number of data granules locked by a transaction, the mean number of writelocks and readlocks held by a transaction, and the mean number of locked data granules in a database. These parameters provide more insight into the detailed behavior of transactions and database systems. Finally, we calculate the system throughput and restart rate, which are the two principal performance measures.
A model-based approach to achieve organizational information assurance
Authors: Forouzan Golshani
Venue:  (2003)

The protection of information is essential to the success of any organization. In spite of the growing prevalence of information theft, organizations continue to be ill-prepared to deal with the possibility of both physical and electronic assaults on their information systems. One way that organizations attempt to become proficient in information assurance is by employing personnel who are certified in Information Technology. This research challenges the tacit assumption that certification is sufficient to ensure a higher level of organizational information assurance. This dissertation compares organizations that employ personnel certified in Information Technology against organizations that do not employ such certified personnel. Because overall information security is bound by its weakest component, it is not necessary to compare all aspects of organizational information security to achieve a valid comparison. This research establishes a reference model that identifies essential practices for the confidentiality of information in storage, and then compares organizations against that reference model. Results generated from more than 130 organizations indicate that, while organizations with certified personnel are slightly more likely to perform essential information security practices, neither group of organizations is performing very well. In one key area, those organizations with certified personnel actually leave themselves more vulnerable to electronic attack than other organizations, as nearly half of the organizations with certified personnel acknowledge having external network connections that circumvent organizational firewalls. More stunning than the poor performance of many organizations are the indications that organizations holding critical consumer credit information do not even acknowledge a direct responsibility to safeguard that information. This leads to the conclusion that information assurance is more dependent on information security awareness than on technological advances. Another important conclusion is that organizations desiring certified personnel must be willing to pay for the cost of the certification. Over 80% of all personnel certifications represented in this research were fully funded by the organization.
Hierarchical graph indexing
Authors: James Abello, Yannis Kotidis
Venue: Proceedings of the twelfth international conference on Information and knowledge management (2003)

Traffic analysis, in the context of Telecommunications or Internet and Web data, is crucial for large network operations. Data in such networks is often provided as large graphs with hundreds of millions of vertices and edges. We propose efficient techniques for managing such graphs at the storage level in order to facilitate its processing at the interface level(visualization). The methods are based on a hierarchical decomposition of the graph edge set that is inherited from a hierarchical decomposition of the vertex set. Real time navigation is provided by an efficient two level indexing schema called the gkd*-tree. The first level is a variation of a kd-tree index that partitions the edge set in a way that conforms to the hierarchical decomposition and the data distribution (the gkd-tree). The second level is a redundant R-tree that indexes the leaf pages of the gkd-tree. We provide computational results that illustrate the superiority of the gkd-tree against conventional indexes like the kd-tree and the R*-tree both in creation as well as query response times.
The impossibility of affine reconstruction from perspective image pairs obtained by a translating camera with varying parameters
Authors: Zhanyi Hu, Fuchao Wu, Guanghui Wang
Venue: Pattern Recognition Letters (2003)

Contrary to the claim in the literature that the affine reconstruction is possible from two images captured by a translating camera with unknown and varying parameters, we show that such a reconstruction is in fact impossible. In other words, the knowledge that "the camera's motion between the two images is just a pure translation" is an insufficient piece of information for affine reconstruction.
Real Time Inspection of Hidden Worlds
Authors: Alois Ferscha, Markus Keller
Venue: Proceedings of the Seventh IEEE International Symposium on Distributed Simulation and Real-Time Applications (2003)

"Smart Things" are commonly understood as wireless ad-hoc networked, mobile, autonomous, special purpose computing appliances, usually interacting with their environment implicitly via a variety of sensors on the input side and actuators on the output side. Such smart appliances have started to populate the "real world" with "hidden" or "invisible" services, thus building up an "invisible world" of services associated with real world objects. With the embedding of invisible technology into everyday things, however, also the intuitive perception of "invisible services" disappears. We believe that it has potential advantages to support the perception of smart appliance services via novel interactive visual experiences. For this purpose we have developed and built DigiScope, a see-through based visual real time perception system for "invisible worlds" to support interactive theater experience in mixed reality spaces. A case study is presented that demonstrates the use of DigiScope to percept the "invisible services" of our smart Internet appliance SmartCase. Opposed to previous work on mixed reality based augmentation of reality, the DigiScope approach allows for a multiuser, collaborative real time perceptual experience.
Logic optimization on a concurrent processing computer
Authors: F. Theeuwen
Venue: Proceedings of the conference on European design automation (1990)

Optimization of combinational logic plays an important role in the automatic synthesis of integrated circuits, often called Silicon Compilation. The optimization program rewrites a given set of boolean expressions in such a way that, after mapping the expressions onto a set of library cells, an optimal result will be obtained. This optimality can be in terms of area (number of transistors), speed, power consumption or a tradeoff between them. Particular controllers are suitable to be optimized with such a program. A number of packages are developed and described in literature [Thee], [Bar], [Bray]. One of the problems with these packages is the long computer runtime needed for large real world problems. This paper describes the implementation of a logic optimization package described in [Thee] on a supermini computer (The Alliant FX-8) which is able to execute a job concurrently on a number of CPU's. For our application is was necessary to rearrange the program flow in such a way that large parts of the computational work can be done concurrently by different CPU's. To be able to run the program in parallel successfully the next conditions have to be fulfilled:1. The time consuming program parts have to be executed in parallel. This requires that these parts have to be splitted up in a number of subtasks that can be executed (nearly) independent from each other.2. The memory management must be able to support concurrent processing.The paper describes the datastructures and the memory functions that are developed, also details about the implementation of the concurrent parts of the program will be given. A table showing promising results is given.
Convergence analysis for an iterative method for solving nonlinear parabolic systems
Authors: Mohammed Al-Refai
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

Nonlinear parabolic systems of partial differential equations are considered. In a recent work, we have proposed a new iterative method based on the eigenfunction expansion to integrate these systems. In this paper, we prove the convergence of the method on bounded time intervals under certain condition that can be more easily to satisfy. We then show that the solution obtained by the new method will converge to the exact solution for a problem in combustion theory. Moreover, we determine the number of iterations needed to obtain a solution with a predetermined level of accuracy. It is expected that the convergence analysis can be used for similar systems of time dependence.
Human facial illustrations: creation and evaluation
Authors: Richard R. Riesenfeld
Venue:  (2003)

This dissertation presents a method for creating black-and-white illustrations and caricatures of human faces from source photographs and series of perceptual studies aimed at evaluating the effectiveness of the resulting images relative to photographs. The illustrations are generated by superimposing two images: a thresholded image of the output of a computational brightness model and a thresholded luminance image. In addition, a new interactive technique is demonstrated for deforming images of faces to create caricatures that highlight and exaggerate representative facial features. The photographs and black-and-white illustrations are evaluated via psychophysical studies to assess speed and accuracy in learning and recognition tasks. These studies show that the facial illustrations and caricatures generated using these techniques are as effective as photographs in the recognition tasks. In the learning studies, tasks involving illustrations or caricatures were performed significantly faster than the same tasks were performed with photographs. The recognition invariance effect is used as an experimental probe in a functional magnetic resonance imaging (fMRI) experiment. The results of this experiment indicate that viewers may process illustrations differently from photographs.
Chaos theory as a framework for studying information systems
Authors: Gurpreet S. Dhillon, John Ward
Venue: Advanced topics in information resources management (2003)

This paper introduces Chaos Theory as a means of studying information systems. It argues that Chaos Theory, combined with new techniques for discovering patterns in complex quantitative and qualitative evidence, offers a potentially more substantive approach to understand the nature of information systems in a variety of contexts. The paper introduces Chaos Theory concepts by way of an illustrative research design.
Ethical disobedience
Authors: Jessica Litman
Venue: Ethics and Information Technology (2004)

The heated rhetoric surrounding digital copyright in general, and peer-to-peer file sharing in particular, has inspired great confusion about what the copyright law does and does not prohibit. Most of the key legal questions are still unsettled, in part because copyright defendants have run out of money and gone out of business before their cases could go to trial. In that vacuum, some copyright owners are claiming that their preferred rules of conduct are well-established legal requirements. But those claims are strategic; those rules have never been endorsed by the courts. They are made-up rules. There's a difference between our obligation to follow real rules, and our obligation to follow made-up ones. There may be an ethical obligation to follow real rules, even when they seem unreasonable. But we don't have any ethical obligation to follow made-up ones. Indeed, in this context, we may have an ethical obligation to resist them. Some copyright owners believe the law ought to enable them to control essentially all significant uses of their works. The law has never said that, but it gets closer and closer every day. If we behave as though the made-up rules were actually the law, we will make that day come much sooner.
Unique virtues of the Pad&#x00E9; approximant for high-resolution signal processing
Authors: Dževad Belkić
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

This lecture reviews quantum-mechanical signal processing based upon the Padé approximant (PA). We presently link the PA and the Lanczos algorithm to design the Padé-Lanczos approximant (PLA). The PLA is operationalized with the recursive algorithm called the fast Padé transform (FPT) for both parametric and nonparametric estimations of spectra. The FPT for any given power series is defined by the unique quotient of two polynomials. This processor provides a meaningful result even when the original expansion diverges. It can significantly accelerate slowly converging sequences/series. As opposed to a single polynomial, e.g. the fast Fourier transform (FFT), the FPT can analytically continue general functions outside their definition domains. Moreover, we show that the FPT is an efficient solver of generalized eigen-problems e.g. the quantum-mechanical evolution/relaxation matrix U comprised of auto-correlation functions. These generic functions can be either computed theoretically or measured experimentally. Such a concept, put forward as a computational tool, surpasses its initial purpose. Indeed auto-correlation functions represent a veritable alternative formulation of quantum mechanics. This is not just because all the major observables e.g. complete energy spectra, local density of states, quantal rate constants, etc, are expressible through the auto-correlation functions. It is also because these and other observables could be given completely in terms of some appropriate, relatively small informational parts that can be singled out and analyzed separately from the unwanted/redundant remainder of the full data set of auto-correlation functions. The needed dimensionality reduction of original large problems treated by the FPT can be achieved by e.g. windowing using the band-limited decimation. Alternatively, as abundantly done in this work, the Lanczos tridiagonalization can be employed yielding sparse Jacobi matrices in terms of the Lanczos coupling parameters {αn, βn} that have their very important physical interpretations. The FPT is naturally ingrained in the Schrödinger picture of quantum mechanics and in the total time-independent Green function for the studied system. This yields a versatile framework for a unified treatment of spectroscopy and collision within signal processing and quantum mechanics.
Multi-level synthesis on PALs
Authors: Gabrielle Saucier, Pascal Sicard, Laurent Bouchet
Venue: Proceedings of the conference on European design automation (1990)

This paper presents a decomposition method for logic mapping on PALs. It addresses a large variety of PALs. For functions having too many variables, a novel approach based on algebraic divisions is proposed. It is followed by an interesting reinjection phase tending to suppress unusefull decompositions. Both critical path and PAL numbers are optimised.
Quantum entanglement as a new information processing resource
Authors: Jozef Gruska
Venue: New Generation Computing (2003)

Quantum entanglement, a special correlation that can exist between subsystems of quantum multipartite systems, is increasingly seen as one of the most specific physical resources of quantum world. It is a resource that is not only behind the fact that quantum information processing can be more efficient than classical ones and that quantum communication can be both more efficient and more secure than classical one, but, and this is perhaps the main point, also behind an increasing confidence that quantum entanglement can lead to new quantum information processing technology and to a new, and deeper, understanding of important and complex (quantum) physics phenomena.In this paper we concentrate on this new physical resource and on its various, sometimes even mysterious, consequences and impacts on computations and communications. In addition, we briefly summarize main problems and outcomes of the research concentrating on the understanding of the structure, laws and limitations of entanglement itself.
Managing Supply Networks: Symptom Recognition and Diagnostic Analysis with Web Services
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 7 - Volume 7 (2004)

As supply chain managers spend well above 60% of their total working time remedying disruptions along the value chain, they require the support of inter-organizational information systems that allow them to focus their attention on the critical problems. In addition, each action they decide on needs to be aligned with the overall network strategy to sustain thesupply chain's competitive edge. However, research has only been very limited in this area. Commercially available Supply Chain Event Management-suites are a first step into this direction but so far lack important aspects like diagnostic analyses and integration into existing management and controlling frameworks. Based on a network-wide capturing of performancemeasurement data and alerting mechanisms in case key figures or process metrics do not meet their targets or exceed pre-set limits, this paper describes a computerized symptom-to-therapy cycle starting with recognizing performance deviations all the way to diagnosing the underlying root causes and supplying management with possible reaction measures to steer clear of the problem. At FORWIN this concept has been realized in a web-based prototype that will be presented to show these principles work in practice. The modules for symptom recognition and diagnosis will be discussed in detail. The article concludes with a brief outlook on future research.
Application of Multiblock Grid and Dual-Level Parallelism in Coastal Ocean Circulation Modeling
Authors: Phu Luong, Clay P. Breshears, Le N. Ly
Venue: Journal of Scientific Computing (2004)

Numerical grid generation techniques play an important role in the numerical solution of partial differential equations on arbitrarily shaped regions. For coastal ocean modeling, in particular, a one-block grid covering the region under study is commonly used. Most bodies of water of interest have complicated coastlines; e.g., the Persian Gulf and Mediterranean Sea. Since such one-block grids are not boundary conforming, the number of unused grid points can be a relatively large portion of the entire domain space. Other disadvantages of using a one block grid include large memory requirements and long computer processing time. Multiblock grid generation and dual-level parallel techniques are used to overcome these problems. Message Passing Interface (MPI) is used to parallelize the Multiblock Grid Princeton Ocean Model (MGPOM) such that each grid block is assigned to a unique processor. Since not all grid blocks are of the same size, the workload varies between MPI processes. To alleviate this, OpenMP dynamic threading is used to improve load balance. Performance results from the MGPOM model on a one-block grid, a twenty block grid, and a forty-two block grid after a 90-day simulation for the Persian Gulf demonstrate the efficacy of the dual-level parallel code version.