ppxscal/embedding_network huggingface dataset:
Broadband maximum likelihood wave parameter estimation using polarization sensitive arrays
Authors: D. Maiwald, D. V. Sidorovitch, J. F. Bohme
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1993. ICASSP-93 Vol 4., 1993 IEEE International Conference on - Volume 04 (1993)

The estimation of wave parameters using polarization sensitive arrays is addressed. Diversely polarized antennas are used, e.g. in radar and communication systems. A seismic application is presented. The wave parameters are estimated using a broadband maximum likelihood estimation procedure. To determine the maximum likelihood estimates, a complicated optimization problem has to be solved. The genetic algorithm and the EM algorithm are used to overcome this difficulty. Finally the application of the algorithm to real seismic data is studied.
Specular Flow and the Recovery of Surface Structure
Authors: Stefan Roth, Michael J. Black
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 2 (2006)

In scenes containing specular objects, the image motion observed by a moving camera may be an intermixed combination of optical flow resulting from diffuse reflectance (diffuse flow) and specular reflection (specular flow). Here, with few assumptions, we formalize the notion of specular flow, show how it relates to the 3D structure of the world, and develop an algorithm for estimating scene structure from 2D image motion. Unlike previous work on isolated specular highlights we use two image frames and estimate the semi-dense flow arising from the specular reflections of textured scenes. We parametrically model the image motion of a quadratic surface patch viewed from a moving camera. The flow is modeled as a probabilistic mixture of diffuse and specular components and the 3D shape is recovered using an Expectation-Maximization algorithm. Rather than treating specular reflections as noise to be removed or ignored, we show that the specular flow provides additional constraints on scene geometry that improve estimation of 3D structure when compared with reconstruction from diffuse flow alone. We demonstrate this for a set of synthetic and real sequences of mixed specular-diffuse objects.
TCP-aware resource allocation in CDMA networks
Authors: Majid Ghaderi, Ashwin Sridharan, Hui Zang, Don Towsley, Rene Cruz
Venue: Proceedings of the 12th annual international conference on Mobile computing and networking (2006)

TCP is the dominant transport protocol over both wired and wireless links. It is however, well known that TCP is not suitable for wireless networks and several solutions have been proposed to rectify this shortcoming. In this work, we explore cross-layer optimization of the rate adaptation feature of cellular networks to optimize throughput of a single long-lived TCP session. Modern cellular networks rate RF technology that allows them to dynamically vary the wireless channel rate in response to user demand and channel conditions. However, the set of data rates as well as the scheduler's rate adaptation policy are typically chosen to optimize throughput for inelastic applications. In order to optimize such a system for TCP, we propose a two state TCP-aware scheduler that switches between two chanrates as a function of the TCP sending rate. We develop a fluid model of the steady-state behavior of a TCP session in such a system and derive analytical expressions for TCP throughput that explicitly account for rate variability as well as the dependency between the scheduler and TCP. Using the model we choose RF layer parameters that, in conjunction with the TCP-aware scheduler, improve term throughput of a single TCP flow by 15.25%. We also compare our analytical results against those obtained from ns-2 simulations and confirm that our model indeed closely approximates TCP behavior in such an environment.
Mapping deontic operators to abductive expectations
Authors: Marco Alberti, Marco Gavanelli, Evelina Lamma, Paola Mello, Paolo Torroni, Giovanni Sartor
Venue: Computational Mathematical Organization Theory (2006)

Deontic concepts and operators have been widely used in several fields where representation of norms is needed, including legal reasoning and normative multi-agent systems.The EU-funded SOCS project has provided a language to specify the agent interaction in open multi-agent systems. The language is equipped with a declarative semantics based on abductive logic programming, and an operational semantics consisting of a (sound and complete) abductive proof procedure. In the SOCS framework, the specification is used directly as a program for the verification procedure.In this paper, we propose a mapping of the usual deontic operators (obligations, prohibition, permission) to language entities, called expectations, available in the SOCS social framework. Although expectations and deontic operators can be quite different from a philosophical viewpoint, we support our mapping by showing a similarity between the abductive semantics for expectations and the Kripke semantics that can be given to deontic operators.The main purpose of this work is to make the computational machinery from the SOCS social framework available for the specification and verification of systems by means of deontic operators.
Amnesia and the Declarative/Nondeclarative Distinction: A Recurrent Network Model of Classification, Recognition, and Repetition Priming
Authors: Annette Kinder, David R. Shanks
Venue: Journal of Cognitive Neuroscience (2001)

A key claim of current theoretical analyses of the memory impairments associated with amnesia is that certain distinct forms of learning and memory are spared. Supporting this claim, B. J. Knowlton and L. R. Squire found that amnesic patients and controls were indistinguishable in their ability to learn about and classify strings of letters generated from a finite-state grammar, but that the amnesics were impaired at recognizing the training strings. We show, first, that this pattern of results is predicted by a single-system connectionist model of artificial grammar learning (AGL) in which amnesia is simulated by a reduced learning rate. We then show in two experiments that a counterintuitive assumption of this model, that classification and recognition are functionally identical in AGL, is correct. In three further simulation studies, we demonstrate that the model also reproduces another type of dissociation, namely between recognition memory and repetition priming. We conclude that the performance of amnesic patients in memory tasks is better understood in terms of a nonselective, rather than a selective, memory deficit.
Algebraic fusion of functions with an accumulating parameter and its improvement
Authors: Shin-ya Katsumata, Susumu Nishimura
Venue: Proceedings of the eleventh ACM SIGPLAN international conference on Functional programming (2006)

We present a unifying solution to the problem of fusion of functions, where both the producer function and the consumer function have one accumulating parameter. The key idea in this development is to formulate the producer function as a function which computes over a monoid of data contexts. Upon this formulation, we develop a fusion method called algebraic fusion based on the elementary theory of universal algebra and monoids. The producer function is fused with a monoid homomorphism that is derived from the definition of the consumer function, and is turned into a higher-order function f that computes over the monoid of endofunctions.We then introduce a general concept called improvement, in order to reduce the cost of computing over the monoid of endofunctions (i. e., function closures). An improvement of the function f via a monoid homomorphism h is a function g that satisfies f =h ºg. This provides a principled way of finding a first-order function representing a solution to the fusion problem. It also presents a clean and unifying account for varying fusion methods that have been proposed so far. Furthermore, we show that our method extends to support partial and infinite data structures, by means of an appropriate monoid structure.
Functional Parcellation of Attentional Control Regions of the Brain
Authors: Marty G. Woldorff, Chad J. Hazlett, Harlan M. Fichtenholtz, Daniel H. Weissman, Anders M. Dale, Allen W. Song
Venue: Journal of Cognitive Neuroscience (2004)

Recently, a number of investigators have examined the neural loci of psychological processes enabling the control of visual spatial attention using cued-attention paradigms in combination with event-related functional magnetic resonance imaging. Findings from these studies have provided strong evidence for the involvement of a fronto-parietal network in attentional control. In the present study, we build upon this previous work to further investigate these attentional control systems. In particular, we employed additional controls for nonattentional sensory and interpretative aspects of cue processing to determine whether distinct regions in the fronto-parietal network are involved in different aspects of cue processing, such as cue-symbol interpretation and attentional orienting. In addition, we used shorter cue-target intervals that were closer to those used in the behavioral and event-related potential cueing literatures. Twenty participants performed a cued spatial attention task while brain activity was recorded with functional magnetic resonance imaging. We found functional specialization for different aspects of cue processing in the lateral and medial subregions of the frontal and parietal cortex. In particular, the medial subregions were more specific to the orienting of visual spatial attention, while the lateral subregions were associated with more general aspects of cue processing, such as cue-symbol interpretation. Additional cue-related effects included differential activations in midline frontal regions and pretarget enhancements in the thalamus and early visual cortical areas.
A multiband exponential rate operator for musical transient analysis
Authors: R. Mani, S. H. Nawab
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1995. on International Conference - Volume 02 (1995)

The exponential rate operator (ERO) is presented for determining the "instantaneous exponential rate" of the amplitude modulation during musical transients. Its extension to multiband signal representations such as STFT and wavelet transforms is also described. Sensitivity of the ERO to white noise is examined and computational efficiency of the STFT-based ERO is discussed. Examples involving synthetic and real musical transients illustrate the usefulness of ERO analysis.
Swirling-sweepers: constant-volume modeling
Authors: Alexis Angelidis, Marie-Paule Cani, Geoff Wyvill, Scott King
Venue: Graphical Models (2006)

Swirling-sweepers is a new method for modeling shapes while preserving volume. The artist describes a deformation by dragging a point along a path. The method is independent of the geometric representation of the shape. It preserves volume and avoids self-intersections, both local and global. It is capable of unlimited stretching and the deformation can be constrained to affect only a part of the model. We argue that all of these properties are necessary for interactive modeling if the user is to have the impression that he or she is shaping a real material. Our method is the first to implement all five.
Activity centered design: towards a theoretical framework for CSCL
Authors: Bernard R. Gifford, Noel D. Enyedy
Venue: Proceedings of the 1999 conference on Computer support for collaborative learning (1999)

Computers have not yet had the profound impact on classroom practice that has been predicted. Given the proven potential of computer-mediated instruction, what can account for the lack of progress? This paper explores the theoretical underpinnings of many of the existing computer-mediated learning environments and suggests that the learning theories that lie behind them lead to designs that do not fit with nor change the basic participation structures of the classroom. We argue instead for Activity Centered Design (ACD), a model of design for Computer Supported Collaborative Learning environments, based on the following assumptions: that activity is mediated by cultural tools, that activity must be conceptualized on a number of interdependent levels, and that conceptual understanding is first established socially. We then critique our own existing learning environment, the Probability Inquiry Environment, from the ACD perspective.
High-Dimensional Similarity Searches Using A Metric Pseudo-Grid
Authors: Christian Digout, Mario A. Nascimento
Venue: Proceedings of the 21st International Conference on Data Engineering Workshops (2005)

Despite the proposal of numerous tree-based access structures for high dimensional similarity searches, techniques based on a sequential scan have been shown to be simple yet quite efficient alternatives. Given that random accesses to disk are expensive, a linear scan of the (smaller) pre-processed dataset is often much more efficient than even a relatively small number of random disk accesses yielded by tree-based indices. In this paper we present a technique which uses a pseudo-partition of a general metric space analog to the VA-file's partition of the vector space. The rationale is to use a number of pivot objects in the metric space, each one determining a number of hyper-rings in this space. The intersection of those rings, determine pseudo-cells analog to the VA-file cells in the vector space. In order to speedup query processing the data set is clustered (using any applicable clustering technique). Clusters not intersecting cells intersected by the query region cannot contribute to the answer set. Thus, only a few clusters are searched using an I/O efficient linear scan of the cluster's data. The proposed technique, which we call the M-GRID, is, by construction, applicable to both general metric spaces and to traditional vector spaces as long as a metric distance function is used. The M-GRID is robust to several parameters and experiments with synthetic and real data sets show that it is able to perform nearest neighbor queries up to 10 times faster than the VA-File.
On the extreme eigenvalues of regular graphs
Authors: Sebastian M. Cioaba
Venue: Journal of Combinatorial Theory Series B (2006)

In this paper, we present an elementary proof of a theorem of Serre concerning the greatest eigenvalues of k-regular graphs. We also prove an analogue of Serre's theorem regarding the least eigenvalues of k-regular graphs: given ε > 0, there exist a positive constant c = c(ε, k) and a non-negative integer g = g(ε, k) such that for any k-regular graph X with no odd cycles of length less than g, the number of eigenvalues µ of X such that µ ≤ - (2 - ε) √k - 1 is at least c|X|. This implies a result of Winnie Li.
First Experiences with Group Projects in CSE Education
Authors: Martin Bernreuther, Hans-Joachim Bungartz
Venue: Computing in Science and Engineering (2006)

The various educational workshops at CSE-related conferences reveal that there is an ongoing open discussion on how to define the relevant aspects of this discipline, on how to integrate the identified topics into the curricula, and, of course, on how to design suitable course formats -- or briefly, how to teach CSE in an appropriate way. One question more and more addressed in such discussions is to what extent and how methods established in software engineering can or even must be adopted. A second evergreen issue (not restricted to CSE programs, of course) is whether soft skills such as teamwork, project management, or leadership should be taught in special courses or better imparted within suitable CSE-related modules. In this contribution, we report our experiences with project-based and software-focused CSE education. The discussion of expectations and outcomes covers both the software-related issues and the main project-related aspects.
Upper and lower solution method for fourth-order four-point boundary value problems
Authors: Qin Zhang, Shihua Chen, Jinhu Lü
Venue: Journal of Computational and Applied Mathematics (2006)

This paper is concerned with the fourth-order ordinary differential equation u(4)(t) = f(t, u(t), u"(t)), 0 < t < 1 with the four-point boundary conditions u(0) = u(1) = 0, au"(ξ1) - bu'"(ξ1) = 0, cu"(ξ2) + du'"(ξ2) = 0, where ξi ∈ [0, 1] (i = 1, 2) and a, b, c, d are nonnegative constants satisfying ad + bc + ac(ξ2 - ξ1) > 0. Some new existence results are obtained by developing the upper and lower solution method and the monotone iterative technique.
Reconstructing XML Subtrees from Relational Storage of XML documents
Authors: Artem Chebotko, Dapeng Liu, Mustafa Atay, Shiyong Lu, Farshad Fotouhi
Venue: Proceedings of the 21st International Conference on Data Engineering Workshops (2005)

Numerous researchers have proposed to use relational databases to store and query XML documents. One important component of such systems is the XML subtree reconstruction, which reconstructs the subtrees rooted at the matching nodes of an XML query and returns them to the user as the query result. Existing reconstruction algorithms either do not support recursive XML view schema, or require expensive nested queries or joins of multiple relations. In this paper, we propose an efficient XML subtree reconstruction algorithm, Reconstruct, which overcomes these limitations and uses an efficient stack-based structural join algorithm to recover all the parent-child relationships between elements. One salient advantage of this algorithm is that it employs the inlining feature of the inlining-based storage of XML documents, which is known as one of the best relational XML storage schemes. Both our algorithmic analysis and experimental study show that Reconstruct is efficient and scalable.
Sixth-Sense: Context Reasoning for Potential Objects Detection in Smart Sensor Rich Environment
Authors: Bin Guo, Satoru Satake, Michita Imai
Venue: Proceedings of the IEEE/WIC/ACM international conference on Intelligent Agent Technology (2006)

A new system named Sixth-Sense is proposed for obtaining physical world information in smart space. Our view is object-centered and sensors are attached to several objects in the space. What we focus is to use the smart sensor attached objects to obtain information from no sensor attached objects, i.e., the so called potential objects detection problem. The Sixth-Sense resolves this problem by Sixth-Sense Skeleton and inference rules. A series of inference rules are presented and illustrated.
Flow blocks as a conceptual bridge between understanding the structure and behavior of a complex causal system
Authors: Oren Zuckerman, Tina Grotzer, Kelly Leahy
Venue: Proceedings of the 7th international conference on Learning sciences (2006)

Complexity exists in the world all around us. While it has garnered the focus of scientists in forms such as quantum mechanics and chaos theory, complexity also exists in the every day world. For instance, in order to understand the transmission of a common cold, one needs to understand probabilistic causation, branching causal patterns, and distributed agency. In this paper we argue that students need opportunities to learn the causal concepts related to complexity and we review research in support of this assertion. We introduce a set of materials called "Flow Blocks" that are designed to give children the opportunity to explore complex causal relationships and their analogical relationships to real world systems. We go on to share exploratory research that we conducted using Flow Blocks and to discuss what the finding suggest for learning about the nature of complexity.
Attack detection in time series for recommender systems
Authors: Sheng Zhang, Amit Chakrabarti, James Ford, Fillia Makedon
Venue: Proceedings of the 12th ACM SIGKDD international conference on Knowledge discovery and data mining (2006)

Recent research has identified significant vulnerabilities in recommender systems. Shilling attacks, in which attackers introduce biased ratings in order to influence future recommendations, have been shown to be effective against collaborative filtering algorithms. We postulate that the distribution of item ratings in time can reveal the presence of a wide range of shilling attacks given reasonable assumptions about their duration. To construct a time series of ratings for an item, we use a window size of k to group consecutive ratings for the item into disjoint windows and compute the sample average and sample entropy in each window. We derive a theoretically optimal window size to best detect an attack event if the number of attack profiles is known. For practical applications where this number is unknown, we propose a heuristic algorithm that adaptively changes the window size. Our experimental results demonstrate that monitoring rating distributions in time series is an effective approach for detecting shilling attacks.
The Theory Grid and Grid Theorists
Authors: Jingde Cheng, Shinsuke Nara, Takahiro Koh, Yuichi Goto
Venue: Proceedings of the Second International Conference on Semantics, Knowledge, and Grid (2006)

This paper proposes a novel research direction: to build the Theory Grid as cooperatively shared formal theories within a virtual organization, and then to implement Grid Theorists as the wisdom of crowds working based on the Theory Grid such that the grid theorists have the ability to find new theorems and propose new questions semi-automatically.
Conditional steady-state bounds for a subset of states in Markov chains
Authors: Tuǧrul Dayar, Nihal Pekergin, Sana Younès
Venue: Proceeding from the 2006 workshop on Tools for solving structured Markov chains (2006)

The problem of computing bounds on the conditional steady-state probability vector of a subset of states in finite, ergodic discrete-time Markov chains (DTMCs) is considered. An improved algorithm utilizing the strong stochastic (st-)order is given. On standard benchmarks from the literature and other examples, it is shown that the proposed algorithm performs better than the existing one in the strong stochastic sense. Furthermore, in certain cases the conditional steady-state probability vector of the subset under consideration can be obtained exactly.
Designing a successful trading agent for supply chain management
Authors: Minghua He, Alex Rogers, Xudong Luo, Nicholas R. Jennings
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

This paper describes the design and evaluation of Southampton-SCM, the runner-up in the 2005 International Trading Agent Supply Chain Management Competition (TAC SCM). In particular, we focus on the way in which our agent purchases components using a mixed procurement strategy (combining long and short term planning) and how it sets its prices according to the prevailing market situation and its own inventory level (because this adaptivity and flexibility are key to its success). We analyse our buying and selling strategies in the actual competition and in controlled experiments. Through this evaluation, we show that SouthamptonSCM performs well across a broad range of environments.
Enhancing Eigenvalue Approximation by Gradient Recovery
Authors: Ahmed Naga, Zhimin Zhang, Aihui Zhou
Venue: SIAM Journal on Scientific Computing (2006)

The polynomial preserving recovery (PPR) is used to enhance the finite element eigenvalue approximation. Remarkable fourth order convergence is observed for linear elements under structured meshes as well as unstructured initial meshes (produced by the Delaunay triangulation) with the conventional bisection refinement.