ppxscal/embedding_network huggingface dataset:
Model-based object recognition using geometric invariants of points and lines
Authors: Bong Seop Song, Kyoung Mu Lee, Sang Uk Lee
Venue: Computer Vision and Image Understanding (2001)

In this paper, we derive new geometric invariants for structured 3D points and lines from single image under projective transform, and we propose a novel model-based 3D object recognition algorithm using them. Based on the matrix representation of the transformation between space features (points and lines) and the corresponding projected image features, new geometric invariants are derived via the determinant ratio technique. First, an invariant for six points on two adjacent planes is derived, which is shown to be equivalent to Zhu's result [1], but in simpler formulation. Then, two new geometric invariants for structured lines are investigated: one for five lines on two adjacent planes and the other for six lines on four planes. By using the derived invariants, a novel 3D object recognition algorithm is developed, in which a hashing technique with thresholds and multiple invariants for a model are employed to overcome the over-invariant and false alarm problems. Simulation results on real images show that the derived invariants remain stable even in a noisy environment, and the proposed 3D object recognition algorithm is quite robust and accurate.
Service-constrained network design problems
Authors: Madhav V. Marathe, R. Ravi, Ravi Sundaram
Venue: Nordic Journal of Computing (1996)

Several practical instances of network design problems often require the network to satisfy multiple constraints. In this paper, we focus on the following problem (and its variants): find a low-cost network, under one cost function, that services every node in the graph, under another cost function, (i.e., every node of the graph is Within a prespecified distance from the network). Such problems find applications in optical network design and the efficient maintenance of distributed databases.We utilize the framework developed in Marathe et al. [1995] co formulate these problems as bicriteria network design problems, and present approximation algorithms for a class of service-constrained network design problems. We also present lower bounds on the approximability of these problems that demonstrate that our performance ratios are close to best possible.
Improved bounds on the weak Pigeonhole principle and infinitely many primes from weaker axioms
Authors: Albert Atserias
Venue: Theoretical Computer Science (2003)

We show that the known bounded-depth proofs of the Weak Pigeonhole Principle PHPn2n in size nO(log(n)) are not optimal in terms of size. More precisely, we give a size-depth trade-off upper bound: there are proofs of size nO(d(log(n))2/d) and depth O(d). This solves an open problem of Maciel et al. (Proceedings of the 32nd Annual ACM Symposium on the Theory of Computing, 2000). Our technique requires formalizing the ideas underlying Nepomnjascij's Theorem which might be of independent interest. Moreover, our result implies a proof of the unboundedness of primes in Iδ0 with a provably weaker 'large number assumption' than previously needed.
An architecture for the integration of decision making support functionalities
Authors: Guisseppi A. Forgionne
Venue: Decision making support systems: achievements, trends and challenges for (2002)

Various information systems have evolved to support the decision making process. There are decision support systems (DSS), executive information systems (EIS), artificially intelligent systems (AIS), and integrated combinations of these systems. Each of the individual systems supports particular phases and steps of the decision making process, but none of the individual systems supports the entire process in an integrated and complete manner. The integrated systems alleviate the support deficiencies, and each of the integration approaches has specific advantages and disadvantages. By studying these advantages and disadvantages, researchers and practitioners can better design, develop, and implement robust decision making support systems. This chapter facilitates such study by presenting and illustrating the underlying information system architectures for robust decision making support.
Dynamic Vehicle Dispatching: Optimal Heavy Traffic Performance and Practical Insights
Authors: Noah Gans, Garrett Van Ryzin
Venue: Operations Research (1999)

We analyze a general model of dynamic vehicle dispatching systems in which congestion is the primary measure of performance. In the model, a finite collection of tours are dynamically dispatched to deliver loads that arrive randomly over time. A load waits in queue until it is assigned to a tour. This representation, which is analogous to classical set-covering models, can be used to study a variety of dynamic routing and load consolidation problems. We characterize the optimal work in the system in heavy traffic using a lower bound from our earlier work (Gans and van Ryzin 1997) and an upper bound which is based on a simple batching policy. These results give considerable insight into how various parameters of the problem affect system congestion. In addition, our analysis suggests a practical heuristic which, in simulation experiments, significantly outperforms more conventional dispatching policies. The heuristic uses a few simple principles to control congestion, principles which can be easily incorporated within classical, static routing algorithms.
Simplification of non-deterministic multi-valued networks
Authors: Alan Mishchenko, Robert Brayton
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

We discuss the simplification of non-deterministic MV networks and their internal nodes using internal flexibilities. Given the network structure and its external specification, the flexibility at a node is derived as a non-deterministic MV relation. This flexibility is used to simplify the node representation and enhance the effect of Boolean resubstitution. We show that the flexibility derived is maximum. The proposed approach has been implemented and tested in MVSIS [16]. Experimental results show that it performs well on a variety of MV and binary benchmarks.
Least-squares fuzzy regression with fuzzy random variables
Authors: A. Wünsche, W. Näther
Venue: Fuzzy Sets and Systems (2002)

Let X˜,Y˜ be two convex fuzzy random variables on Rn. Using a suitable metric we prove that the conditional expectation E(Y˜ | X˜) is the best approximation of Y˜ by measurable functions of X˜. This generalizes the analogous and well known property for real random variables. A further topic is the approximation of Y˜ by a linear function of X˜. In special cases and by use of Hukuhara's difference between fuzzy sets, we obtain formulas which are analogous to the classical structure. Contrary to the classical fact, however, the conditional expectation of Gaussian fuzzy random variables in general does not coincide with the linear regression function.
Data mining, national security, privacy and civil liberties
Authors: Bhavani Thuraisingham
Venue: ACM SIGKDD Explorations Newsletter (2002)

In this paper, we describe the threats to privacy that can occur through data mining and then view the privacy problem as a variation of the inference problem in databases.
Monotonic complements for independent data warehouses
Authors: D. Laurent, J. Lechtenbörger, N. Spyratos, G. Vossen
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (2001)

Views over databases have regained attention in the context of data warehouses, which are seen as materialized views. In this setting, efficient view maintenance is an important issue, for which the notion of self-maintainability has been identified as desirable. In this paper, we extend the concept of self-maintainability to (query and update) independence within a formal framework, where independence with respect to arbitrary given sets of queries and updates over the sources can be guaranteed. To this end we establish an intuitively appealing connection between warehouse independence and view complements. Moreover, we study special kinds of complements, namely monotonic complements, and show how to compute minimal ones in the presence of keys and foreign keys in the underlying databases. Taking advantage of these complements, an algorithmic approach is proposed for the specification of independent warehouses with respect to given sets of queries and updates.
Combining Column Generation and Lagrangean Relaxation to Solve a Single-Machine Common Due Date Problem
Authors: Marjan van den Akker, Han Hoogeveen, Steefvan de Velde
Venue: INFORMS Journal on Computing (2002)

Column generation has proved to be an effective technique for solving the linear programming relaxation ofhuge set covering or set partitioning problems, and column generation approaches have led to state-of-the-art so-called branch-and-price algorithms for various archetypical combinatorial optimization problems. We use a combination of column generation and Lagrangean relaxation to tackle a single-machine common due date problem, where Lagrangean relaxation is exploited for early termination of the column generation algorithm and for speeding up the pricing algorithm. We show that the Lagrangean lower bound dominates the lower bound that can be derived from the column generation algorithm when applied to the standard linear programming formulation, but we also show how the linear programming formulation can be adapted such that the corresponding lower bound is equal to the Lagrangean lower bound.Our comprehensive computational study shows that the combined algorithm is by far superior to two existing purely column generation algorithms: it solves instances with up to 125 jobs to optimality, while a purely column generation algorithm can solve instances with up to only 60 jobs.
Performance of an OFDM Based Downlink Multiple Access System for Indoor Wireless Communications
Authors: Venkatesh Rajendran, Karthikeyan Sundaresan, Srikanth Subramanian
Venue: Wireless Personal Communications: An International Journal (2003)

We have analyzed the downlink performance of a multiuser Orthogonal Frequency Division Multiplexing based multiple access system for indoor wireless communications. The optimization problem for minimizing the total transmit power from a base station while satisfying the bit-rate and bit-error rate criterion of the various portable users in the system has been outlined. The analytical solution obtained cannot be realized in a simple manner and we present a realizable method for the combined allocation of subcarriers, modulation mode, and power to the signals transmitted to the different users. Simulation results are used to compare the performance of the analytical solution with that using the new method under various channel conditions. Performance comparisons between the new method and an OFDM-TDMA system clearly indicate the advantages of the new algorithm under most conditions. The correlation of the frequency-domain channel strengths among the various users is shown to have an influence on the performance of the new algorithm.
Using Hilbert curve in image storing and retrieving
Authors: Zhexuan Song, Nick Roussopoulos
Venue: Information Systems (2002)

In this paper, we propose a method to accelerate the speed of subset query on uncompressed images. First, we change the method to store images: the pixels of images are stored on the disk in the Hilbert order instead of row-wise order that is used in traditional methods. After studying the properties of the Hilbert curve, we give a new algorithm which greatly reduces the number of data segments in subset query range. Although, we have to retrieve more data than necessary, because the speed of sequential readings is much faster than the speed of random access readings, it takes about 10% less elapsed time in our algorithm than in the traditional algorithms to execute the subset queries. In some systems, the saving is as much as 90%.
On intuitionistic gradation of openness
Authors: Tapas Kumar Mondal, S. K. Samanta
Venue: Fuzzy Sets and Systems (2002)

In this paper, we introduce a concept of intuitionistic gradation of openness on fuzzy subsets of a nonempty set X and define an intuitionistic fuzzy topological space. We prove that the category of intuitionistic fuzzy topological spaces and gradation preserving mappings is a topological category. We study compactness of intuitionistic fuzzy topological spaces and prove an analogue of Tychonoff's theorem.
Dynamics of Two- and Three-Worker "Bucket Brigade" Production Lines
Authors: John Bartholdi,  III, Leonid A. Bunimovich, Donald D. Eisenstein
Venue: Operations Research (1999)

We describe all possible asymptotic behavior of "bucket brigade" production lines with two or three workers, each characterized by a constant work velocity. The results suggest wariness in interpreting simulation results. They also suggest a strategy for partitioning a workforce into effective teams to staff the lines.
Efficient multi-modal image registration using local-frequency maps
Authors: J. Liu, B. C. Vemuri, F. Bova
Venue: Machine Vision and Applications (2002)

Fusing of multi-modal data involves automatically estimating the coordinate transformation required to align the multi-modal image data sets. Most existing methods in literature are not fast enough for practical use (taking more than 30 min to 1 h for estimating non-rigid deformations). We propose a very fast algorithm based on matching local-frequency image representations, which naturally allows for processing the data at different scales or resolutions, a very desirable property from a computational efficiency view point. For the rigid motion case, this algorithm involves minimizing - over all rigid transformations - the expectation of the squared difference between the local-frequency representations of the source and target images. In the non-rigid deformations case, we propose to approximate the non-rigid motion by piece-wise rigid motions and use a novel and fast PDE-based morphing technique that estimates this non-rigid alignment. We present implementation results for synthesized and real (rigid) misalignments between CT and MR brain scans. In both the cases, we validate our results against ground truth registrations which for the former case are known and for the latter are obtained from manual registration performed by an expert. Currently, these manual registrations are used in daily clinical practice. Finally, we present examples of non-rigid registration between T1-weighted MR and T2-weighted MR brain images wherein validation is only qualitatively achieved. Our algorithm's performance is comparable to the results obtained from algorithms based on mutual information in the context of accuracy of estimated rigid transforms but is much faster in computational speed.
Active vision and feature selection in evolutionary behavioral systems
Authors: Davide Marocco, Dario Floreano
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

We describe an evolutionary approach to active vision systems for dynamic feature selection. After summarizing recent work on evolution of a simulated active retina for complex shape discrimination, we describe in detail experiments that extend this approach to an all-terrain mobile robot equipped with a mobile camera. We show that evolved robots are capable of selecting simple visual features and actively maintaining them on the same retinal position, which largely simplifies the "recognition" task, in order to generate efficient navigation trajectories with an extremely simple neural control system. Analysis of evolved solutions indicates that robots develop a simple and yet very efficient version of edge detection and visual looming to detect obstacles and move away from them. Two evolved sensory-motor strategies are described, one where the mobile camera is actively used throughout the entire navigation and one where it is used only at the beginning to point towards relevant environmental features. The relationship between these two strategies are discussed in the context of the underlying visuomotor mechanisms and of the evolutionary conditions.
Survey of performance issues in parallel database systems
Authors: Ameet S. Talwadker
Venue: Journal of Computing Sciences in Colleges (2003)

Parallel database systems are being used nowadays in a wide variety of systems, right from database applications to decision support systems. These implementations involve database processing and querying over parallel systems. For the parallel databases to be effective and efficient, various optimizing solutions need to be implemented. These solutions deal with various issues associated with such database systems : query optimization, data allocation within the database, etc.This paper will attempt to give the reader an understanding of the various issues involved in optimizing the performance of a parallel database system. The primary areas of focus will be system architecture, query optimization and data reallocation. It will look at related work done by other authors in this field and hopefully provide a thorough understanding of the solutions in this area.
Interacting with real time simulations: virtual reality in industry applications
Authors: A. Jönsson, J. Bathelt, G. Broman
Venue: Proceedings of the workshop on Virtual environments 2003 (2003)

Modern manufacturing machines are highly multidisciplinary, and with demands on short time-to-market, product development based on traditional prototype testing has become impractical. By using virtual models, it is possible to test large numbers of variants and optimise the product with the aid of a minimum of physical prototypes. Due to the immense development of software and hardware for simulation and visualisation it should today be possible also for small and medium sized enterprises to use methods that just few years ago were too expensive and complicated. There is however still a great need for building knowledge and competence. This work is an early step in a project aiming at a virtual water jet cutting machine to be used by the industrial partner for optimisation during the development process. The possibility of performing real-time simulations of this machine in a virtual environment, using a normal PC and commercial software, will be investigated. Initially strongly simplified models of the system components are used and the focus is on the overall system model and the interaction between the operator and the virtual machine. It is shown that realtime interaction is possible with this system and with the obtained flexibility of the overall virtual model it should be easy to include more realistic component models for improved accuracy in future work. Preliminary results indicate however that to include, for example, flexibility within the mechanic structure, component modelling will be delicate. These models must describe relevant characteristics accurately enough while still being computationally effective enough for real-time interaction and systems optimisation to be possible. This will probably be a challenge in the continuation of the project, even with an expected continued strong development of computer capacity.
Performance evaluation of linear hash structure model in a nested transaction environment
Authors: Malik Ayed Tubaishat, Sanjay Kumar Madria, Bharat Bhargava
Venue: Journal of Systems and Software (2002)

We design and implement a linear hash algorithm in nested transaction environment to handle large amount of data with increased concurrency. Nested transactions allow parallel execution of transactions, and handle transaction aborts, thus provides more concurrency and efficient recovery. We use object-oriented methodology in the implementation which helped in designing the programming components independently. In our model, buckets are modeled as objects and linear hash operations are modeled as methods. The papers contribution is novel in the sense that the system, to our knowledge, is the first to implement linear hashing in a nested transactions environment. We have build a system simulator to analyze the performance. A subtle benefit of the simulator is that it works as the real system with only minor changes.
Cryptanalysis of an optimized protocol for mobile network authentication and security
Authors: C. S. Laih, S. Y. Chiou
Venue: Information Processing Letters (2003)

Yi et al. presented a protocol for mobile network authentication and key distribution based upon the DSA signature scheme. The protocol can be divided into two phases, i,e., registration phase and service phase. In this paper, we show that their scheme is insecure on the registration phase since an attacker can easily forge a certification for any exit or dummy user in their protocol and then pretend to be a legal user to communicate with other entities.
Recent advances on two-dimensional bin packing problems
Authors: Andrea Lodi, Silvano Martello, Daniele Vigo
Venue: Discrete Applied Mathematics (2002)

We survey recent advances obtained for the two-dimensional bin packing problem, with special emphasis on exact algorithms and effective heuristic and metaheuristic approaches.
AAHE's seven principles for good practice applied to an online literacy course
Authors: Brenda Parker, Judith Hankins
Venue: Journal of Computing Sciences in Colleges (2002)

Many of the Computer Science courses at Middle Tennessee State University contain material that a student can access online. However until Spring 2001, the Computer Science department had never offered a course that was completely online. The actual course development began in Fall 2000 when the authors decided that an online Computer Literacy course should be offered. The course was offered for the first time in Spring 2001 and for the second time in Fall 2001.The authors prepared for the course by reviewing the literature and gathering best practices. Many decisions had to be made during the course development phase including developing guidelines to allow a student to enroll in the class, creation of a method to orient the student to the class, deciding course content and makeup of course materials, deciding on the actual course delivery method, and finally determining how testing and grading would be handled. During this decision making phase, the best practices learned were utilized extensively.When the course actually started, there was a whole new set of learning experiences. Learning experiences included the discovery that an online course is definitely not for everyone and that an online course is time-intensive for the instructor even after course materials are developed. This paper will discuss the best practices learned and how they were used to develop course materials and procedures for the class. Finally a list of tips summarizing the learning experiences and recommendations will be shared.
Product Recovery at the Norwegian National Insurance Administration
Authors: Nils Rudi, David F. Pyke, Per Olav Sporsheim
Venue: Interfaces (2000)

Technical aid centers (TACs) in Norway supply devices, such as wheelchairs and hearing aids, to people with handicaps. When a device is returned to a TAC, the TAC staff must decide whether to scrap it or to refurbish it so that it can be used again. The Norwegian National Insurance Administration (NNIA) found that decision makers were scrapping units too frequently, basing their decisions mainly on the hours of labor required to refurbish. We developed a more complete decision-support-system model that accounts for the full cost of sending a unit to the landfill, the cost of refurbishing, the value of parts that can be used elsewhere, the benefits of refurbishing, and so on. Our model is quite simple and visual. Early results suggest that acceptance has been widespread and that decisions have changed, leading to fewer units being scrapped and more being refurbished for redistribution.