ppxscal/embedding_network huggingface dataset:
Quantized CIELab* space and encoded spatial structure for scalable indexing of large color image archives
Authors: E. Albuz
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 04 (2000)

This paper presents a scalable approach for content-based searching and browsing of color image archives using segmented color-layout and spatial structure information. The segmented color layout is computed using quantized CIE-Lab* space, and encoded quadtrees have been used to preserve and represent the structural information. Our careful choice of feature space and associated indexing provides a scalable content-based indexing and retrieval (CBIR) system, where query time is relatively independent of the database size and only depends on the number of images similar to the query image. A sample query in our system takes less than 25 msec on a Pentium 233 MHz machine using a database of 5000 512/spl times/512 size images. This query time is orders of magnitude less than the time on available commercial and research prototypes. Experimental results are also presented showing the quality and efficiency of the indexing system.
Accurate geometrical constraints for the computer aided modelling of the human upper limb
Authors: Davide Gattamelata, Eugenio Pezzuti, Pier Paolo Valentini
Venue: Computer-Aided Design (2007)

For medical and surgical applications, human modelling and simulation have to be very accurate and realistic. This means that both geometries and movements have to be reproduced precisely, investigating both physiological properties and anatomical shapes. This paper deals with the description of geometrical constraints to mimic the movement of the upper limb segments subjected to physical joints. Anatomical studies show that relative motion cannot be approximated with basic constraints such as revolute or spherical joints, but requires the definition of specific geometrical and kinematic pairs. For this purpose, for each joint the authors deduce a set of equations which can be embedded into a virtual environment in order to simulate the relative motion among body segments in a detailed way.
Fast Modular Reduction
Authors: William Hasenplaugh, Gunnar Gaubatz, Vinodh Gopal
Venue: Proceedings of the 18th IEEE Symposium on Computer Arithmetic (2007)

It is widely acknowledged that efficient modular multiplication is a key to high-performance implementation of public-key cryptography, be it classical RSA, Diffie-Hellman, or (hyper-) elliptic curve algorithms. In the recent decade, practitioners have relied mainly on two popular methods: Montgomery Multiplication and regular long-integer multiplication in combination with Barrett's modular reduction technique. In this paper, we propose a modification to Barrett's algorithm that leads to a significant reduction (25% to 75%) in multiplications and additions.
Integration of metacognitive skills in the design of learning objects
Authors: Salvador Sánchez-Alonso, Yianna Vovides
Venue: Computers in Human Behavior (2007)

Recent studies have demonstrated that specific instruction about metacognitive strategies improves achievement, the accuracy of knowledge monitoring, and the application of learning strategies in hypermedia environments. However, there are no models to date for instructional designers who design and develop learning objects for the incorporation of specific scaffolds to aid student reflection about their metacognitive skills; thus making it difficult to identify tasks to orientate learners in improving such skills. In this paper, we propose the use of specific ontologies as the basis for incorporating information about metacognition in learning objects so that a Learning Management System can select and recommend tasks designed for the development and/or improvement of the learners' metacognitive skills within the context of e-learning.
Using pair approximations to predict takeover dynamics in spatially structured populations
Authors: Joshua L. Payne, Margaret J. Eppstein
Venue: Proceedings of the 2007 GECCO conference companion on Genetic and evolutionary computation (2007)

The topological properties of a network directly impact the flow of information through a system. For example, in natural populations, the network of inter-individual contacts affects the rate of flow of infectious disease. Similarly, in evolutionary systems, the topological properties of the underlying population structure affect the rate of flow of genetic information, and thus affect selective pressure. One commonly employed method for quantifying the influence of the population structure on selective pressure is through the analysis of takeover time. In this study, we reformulate takeover time analysis in terms of the well-known Susceptible-Infectious-Susceptible (SIS) model of disease spread. We then adapt an analytical technique, called the pair approximation, to provide a general model of takeover dynamics. We compare the results of this model to simulation data on a total of six regular population structures and discuss the strengths and limitations of the approximation.
A collection of kinesthetic learning activities for a course on distributed computing: ACM SIGACT news distributed computing column 26
Authors: Paolo A. G. Sivilotti, Scott M. Pike
Venue: ACM SIGACT News (2007)

Kinesthetic learning is a process where students learn by actively carrying out physical activities rather than by passively listening to lectures. Pedagogical research has indicated that kinesthetic learning is a fundamental, powerful, and ubiquitous learning style. It resonates with many students across all disciplines and levels of education. The adoption of kinesthetic approaches in college classrooms, however, has been hampered by the difficulty of designing effective activities, as well as the perceived challenges of coordinating these activities. On the other hand, courses on distributed computing, by the very nature of the material they cover, are uniquely suited to exploiting this learning technique. We have developed and piloted a collection of kinesthetic activities for a senior undergraduate or graduate-level course on distributed systems. We give detailed descriptions of these exercises and discuss factors that contribute to their success (or failure). Our hope is that others will adopt these particular activities in their own distributed systems courses as well as use these examples as a pattern for developing new activities.
On seeing and rendering colour gradients
Authors: Alexa I. Ruppertsberg, Anya Hurlbert, Marina Bloj
Venue: Proceedings of the 4th symposium on Applied perception in graphics and visualization (2007)

Ten years ago Greenberg and colleagues presented their framework for realistic image synthesis [Greenberg et al. 1997], aiming "to develop physically based lighting models and perceptually based rendering procedures for computer graphics that will produce synthetic images that are visually and measurably indistinguishable from real-world images", paraphrasing Sutherland's 'ultimate display' [Sutherland 1965]. They specifically encouraged vision researchers to use natural, complex and three-dimensional (3D) visual displays to get a better understanding of human vision and to develop more comprehensive visual models for computer graphics that will improve the efficiency of algorithms. In this paper we follow Greenberg et al.'s directive and analyse colour and luminance gradients in a complex 3D scene. The gradients arise from changes in the light source position and orientation of surfaces. Information in image gradients could apprise the visual system about intrinsic surface reflectance properties or extrinsic illumination phenomena, including shading, shadowing and inter-reflections. Colour gradients induced by inter-reflection may play a similar role to that of luminance gradients in shape-from-shading algorithms; it has been shown that 3D shape perception modulates the influence of inter-reflections on surface colour perception [Bloj et al. 1999]. Here we report a psychophysical study in which we tested whether observers were able to discriminate between gradients due to different light source positions and found that observers reliably detected a change in the gradient information when the light source position differed by only 4 deg from the reference scene (Experiment 1). This sensitivity was mainly based on the luminance information in the gradient (Experiment 2 and 3). We conclude that for a realistic impression of a scene a global illumination algorithm should model the luminance component of inter-reflections accurately, whereas it is less critical to accurately represent the spatial variation in chromaticity.
A distributed object model for the javaTM system
Authors: Ann Wollrath, Roger Riggs, Jim Waldo
Venue: Proceedings of the 2nd conference on USENIX Conference on Object-Oriented Technologies (COOTS) - Volume 2 (1996)

We show a distributed object model for the JavaTM System [1,6] (hereafter referred to simply as "Java") that retains as much of the semantics of the Java object model as possible, and only includes differences where they make sense for distributed objects. The distributed object system is simple, in that a) distributed objects are easy to use and to implement, and b) the system itself is easily extensible and maintainable. We have designed such a model and implemented a system that supports remote method invocation (RMI) for distributed objects in Java. This system combines aspects of both the Modula-3 Network Objects system [3] and Spring's subcontract [8] and includes some novel features. To achieve its goal of seamless integration in the language, the system exploits the use of pickling [14] to transmit arguments and return values and also exploits unique features of Java in order to dynamically load stub code to clients. The final system will include distributed reference-counting garbage collection for distributed objects as well as lazy activation [11,16].
Discovering gene interactions by image analysis and by reverse engineering genetic networks
Authors: Sudhir Kumar, Sethuraman Panchanathan
Venue:  (2006)

The study of gene expression patterns in developing embryos forms a major part of understanding biological systems. Such gene expression patterns offer insights into the regulation and differentiation processes that occur during development. Spatially similar expression patterns from both wild-type and mutant embryos are used to predict and infer gene regulation. From individual gene interactions, gene regulatory networks are built and the structure and dynamics of biological systems are studied. Currently, tens of thousands of fruit fly embryo gene expression pattern images are available. To find spatially similar patterns within this enormous dataset in order to understand gene regulations, computational methods that are based only on image features are needed. Existing techniques for such automated gene expression pattern matching include the Binary Feature Vector (BFV) representation, which is able to retrieve biologically significant images with respect to a query gene expression pattern. In order to find ways to enhance the performance of the BFV representation, this dissertation offers a new metric for similarity measurement and also proposes the separation of multi-domain images into many individual images with single domains. Moreover, the use of Invariant Moment Vectors (IMV), which have been successfully applied in natural image processing, for analyzing fruit fly embryo gene expression pattern images is studied. Another major contribution of this dissertation is to systems biology for understanding the structure of gene regulatory networks. Conflicting Interactions (CIs) are a pair of contradictory interactions, one positive and one negative, from the same regulating gene to the same target gene. None of the existing directed graph approaches for reconstructing regulatory networks models Conflicting Interactions (CIs). This work proposes a modified approach that includes CIs and also determines the effect of their incorporation on the inferred network. In general, the effect of a given gene is not observed more than two levels downstream from where it is transcribed. This was modeled by restricting path traversals to those of length two or less in the network retrieval process. A study of such a restriction, which could potentially decrease the run time, is also given.
Affine invariant wavelet transform
Authors: V. H. S. Ha
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 03 (2001)

We present a two-dimensional wavelet transform that is invariant to affine distortions of the input signal. Affine distortions include geometric effects such as translation, reflection, uniform and anisotropic scaling, rotation, and shearing of the input signal. Invariance of the wavelet transform to affine distortions is achieved in our work by developing an algorithm that reduces replicas of a signal related by affine distortions to a unique prototype signal. The affine invariant wavelet transform is then defined as the two-dimensional wavelet transform of the prototype signal, which provides the wavelet coefficients that are invariant to affine distortions of the input signal. We describe our algorithm and show examples that demonstrate our claims.
A Proposal of Metrics for Botnet Detection Based on Its Cooperative Behavior
Authors: Mitsuaki Akiyama, Takanori Kawamoto, Masayoshi Shimamura, Teruaki Yokoyama, Youki Kadobayashi, Suguru Yamaguchi
Venue: Proceedings of the 2007 International Symposium on Applications and the Internet Workshops (2007)

In this paper, we propose three metrics for detecting botnets through analyzing their behavior. Our social infrastructure (i.e., the Internet) is currently experiencing the danger of bots' malicious activities as the scale of botnets increases. Although it is imperative to detect botnet to help protect computers from attacks, effective metrics for botnet detection have not been adequately researched. In this work we measure enormous amounts of traffic passing through the Asian Internet Interconnection Initiatives (AIII) infrastructure. To validate the effectiveness of our proposed metrics, we analyze measured traffic in three experiments. The experimental results reveal that our metrics are applicable for detecting botnets, but further research is needed to refine their performance.
Complexity Measures for Secure Service-Oriented Software Architectures
Authors: Yanguo (Michael) Liu, Issa Traore
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

As software attacks become widespread, the ability for a software system to resist malicious attacks has become a key concern in software quality engineering. Software attackability is a concept proposed recently in the research literature to measure the extent to which a software system or service could be the target of successful attacks. Like most external attributes, attackability is to some extent disconnected from the internal of software products. To mitigate software attackability, we need to identify and manipulate related internal software attributes. Our goal in this paper is to study software complexity as one such internal attribute. We apply the User System Interaction Effect (USIE) model, a security measurement abstraction paradigm proposed in previous research, to define and validate a sample metric for service complexity. We thereby establish the usefulness of our sample metric through empirical investigation using open source software system as target application.
A Scalable Evidence Based Self-Managing Framework for Trust Management
Authors: Mohammad Waseem Hassan, Richard McClatchey, Ian Willers
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2007)

Centrally managed, traditional security systems put limits on collaborative activities among huge number of entities in current open networks (such as Grids). This requires new approaches to handling security in large distributed systems and the need for new research especially in areas concerned with the provision of security through collaboration. This paper presents the design of a large-scale, self-managing Trust Management Framework (TMF) that makes efficient use of apparently invisible evidences that are scattered across potentially global networks. The TMF's design dictates a layered architecture for capturing evidence at the data layer of a network, transforming it into formed reputations in the information layer and utilizing these reputations to determine trustworthiness of an entity in the knowledge layer of the network. In essence, the main focus of the proposed work is to automate the acquisition of scattered evidence and the formulation, evolution and dissemination of reputations in a scalable way in order to make improved security decisions.
Toward mobile entertainment: A paradigm for narrative-based audio only games
Authors: Timothy E. Roden, Ian Parberry, David Ducrest
Venue: Science of Computer Programming (2007)

The widespread use of sophisticated mobile computing devices has set the stage for a renaissance in audio only entertainment. Traditional visual games are already used widely in cellular phones and similar devices. A significant limitation is the small display size. In contrast, audio only games on suitable mobile hardware need not degrade due to the smaller form factor. This makes audio only games an attractive alternative to visual games. We describe a framework for authoring interactive narrative-based audio only games set in 3D virtual environments. Despite the novelty in audio only gaming, our approach builds on a foundation of several years of research into audio only applications for sight impaired users, augmented reality systems and human-computer interaction studies. In comparison to attempts to provide a realistic user interface, we argue a simple interface enhances both immersion and entertainment value, serendipitously making audio only games practical for mobile computing. Novel features of our system include real-time gameplay and multi-player support. We also describe our software architecture, the current implementation of which uses low-cost existing PC-based hardware and software. In addition, we describe our first game, Dragon's Roar.
Force Feedback is Noticeably Different for Linear versus Nonlinear Elastic Tissue Models
Authors: Sarthak Misra, Allison M. Okamura, K. T. Ramesh
Venue: Proceedings of the Second Joint EuroHaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2007)

Realistic modeling of the interaction between surgical instruments and human organs has been recognized as a key requirement in the development of high-fidelity surgical simulators. Primarily due to computational considerations, most of the past simulation research within the haptics community has assumed linear elastic behavior for modeling tissues, even though human soft tissues generally possess nonlinear viscoelastic properties. Hence, this paper quantitatively compares linear and nonlinear elasticity-based models. It is demonstrated that, for a nonlinear model, the well-known Poynting effect developed during shearing of the tissue results in normal forces not seen in a linear elastic model. The difference in force magnitude and force direction for linear and nonlinear models are larger than the just noticeable difference for contact force and forcedirection discrimination thresholds published in the psychophysics literature, respectively. This work applies a proposed framework for examining the effect of tool-tissue interaction modeling techniques on human perception of surgical simulators with haptic feedback.
Stabilization of smoothness priors deterministic regression TVAR models
Authors: M. Juntunen
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 01 (2000)

A method for the stabilization of time-varying autoregressive models is proposed. The method is based on the smoothness priors regularized prediction equations with nonlinear stability constraints. The problem is solved iteratively with a Gauss-Newton type algorithm in which the original constrained problem is approximated with a sequence of unconstrained problems by using appropriate penalty functions. The performance of the algorithm is studied with a simulation.
Address translation strategies in the texas persistent store
Authors: Sheetal V. Kakkad, Paul R. Wilson
Venue: Proceedings of the 5th conference on USENIX Conference on Object-Oriented Technologies & Systems - Volume 5 (1999)

Texas is a highly portable, high-performance persistent object store that can be used with conventional compilers and operating systems, without the need for a preprocessor or special operating system privileges. Texas uses pointer swizzling at page fault time as its primary address translation mechanism, translating addresses from a persistent format into conventional virtual addresses for an entire page at a time as it is loaded into memory. Existing classifications of persistent systems typically focus only on address translation taxonomies based on semantics that we consider to be confusing and ambiguous. Instead, we contend that the granularity choices for design issues are much more important because they facilitate classification of different systems in an unambiguous manner unlike the taxonomies based only on address translation. We have identified five primary design issues that we believe are relevant in this context. We describe these design issues in detail and present a new general classification for persistence based on the granularity choices for these issues. Although the coarse granularity of pointer swizzling at page fault time is efficient in most case, it is sometimes desirable to use finer-grained techniques. We examine different issues related to fine-grained address translation mechanisms, and discuss why these are not suitable as general-purpose address translation techniques. Instead, we argue for a mixed-granularity approach where a coarse-grained mechanism is used as the primary address translation scheme, and a fine-grained approach is used for specialized data structures that are less suitable for the coarse-grained approach. We have incorporated fine-grained address translation in Texas using the C++ smart pointer idiom, allowing programmers to choose the kind of pointer used for any data member in a particular class definition. This approach maintains the important features of the system: persistence that is orthogonal to type, high performance with standard compilers and operating systems, suitability for huge shared address spaces across heterogeneous platforms, and the ability to optimize away pointer swizzling costs when the persistent store is smaller than the hardware-supported virtual address size.
Minimizing nfa's and regular expressions
Authors: Gregor Gramlich, Georg Schnitger
Venue: Journal of Computer and System Sciences (2007)

We show inapproximability results concerning minimization of nondeterministic finite automata (nfa's) as well as of regular expressions relative to given nfa's, regular expressions or deterministic finite automata (dfa's). We show that it is impossible to efficiently minimize a given nfa or regular expression with n states, transitions, respectively symbols within the factor o(n), unless P=PSPACE. For the unary case, we show that for any @d>0 it is impossible to efficiently construct an approximately minimal nfa or regular expression within the factor n^1^-^@d, unless P=NP. Our inapproximability results for a given dfa with n states are based on cryptographic assumptions and we show that any efficient algorithm will have an approximation factor of at least npoly(logn). Our setup also allows us to analyze the minimum consistent dfa problem.