ppxscal/embedding_network huggingface dataset:
Channel alternation and rotation for sectorized and tiered cellular systems
Authors: Peng-Jun Wan, Ophir Frieder
Venue:  (2003)

A goal of the cellular communication system operator is to maximize subscriber usage within a fixed channel allotment. However, co-channel interference degrades communication quality, further restricting cellular operators to provide reliable service with minimal channels. Currently conventional sectorized cellular systems restrict the reuse of frequency in clusters of 3, 4, or 7 cells. Each cell type is also allocated a disjoint set of frequency channels identical to the number of sectors in a cell. They have not taken full advantages of antenna directivities to enhance frequency reuse efficiency. In this thesis, an innovative architecture design and frequency reuse scheme called Channel Alternation and Rotation (CAR) is proposed. By employing reuse clusters having multiple reuse distances and by allocating additional channel set(s) to each cell type for alternating and rotating frequency channels avoiding nearest front-lobe interferers, CAR allows deploying tighter and fractional reuse factors. As channels are alternated and rotated, the CAR approach also forms low interference regions enabling the deployment of inner-tiered cells that share the same frequencies. In a typical environment, for example, if a carrier to interference ratio (C/I) of 17 dB is required, CAR increases system capacity by up to 31 percent over a conventional sectorized system while CART further increasing system capacity to 75 percent, or up to 55 percent over a two-tiered counterpart. CAR and CART are simple and adaptable. Since no modification to the base stations is required, they introduce no additional costs. With the growing demand in mobile services, the limited available radio spectrum, and the expensive infrastructure build-outs, cellular network designers must strive to achieve highest possible frequency reuse efficiency with minimal costs. An economical and simple approach, such as CAR or CART, is needed to maximally exploit the scarce radio spectrum and existing infrastructures.
Status Report: Practical Software Measurement
Authors: David N. Card, Cheryl L. Jones
Venue: Proceedings of the Third International Conference on Quality Software (2003)

This article summarizes the basic concepts ofPractical Software Measurement (PSM), explainstheir relationship to prior work, then describes thestatus of its transition into practice within the softwareindustry. PSM is rapidly becoming the most popularapproach to measurement for process management. Itis based on the collective experience of a workinggroup representing universities, industry, andgovernment. Key elements of PSM have beendocumented as an international standard andincorporated into the Capability Maturity Model -Integrated.
Project Selection by Constrained Fuzzy AHP
Authors: Mario Enea, Tommaso Piazza
Venue: Fuzzy Optimization and Decision Making (2004)

The selection of a project among a set of possible alternatives is a difficult task decision makers have to face. Difficulties in selecting a project arise because of the different goals involved and because of the large number of attributes to consider. Our approach is based upon a fuzzy extension of the Analytic Hierarchy Process (AHP). This paper focuses on the constraints that have to be considered within fuzzy AHP in order to take in account all the available information. This study demonstrates that by considering all the information deriving from the constraints better results in terms of certainty and reliability can be achieved.
Some Inequalities Concerning Cross-Intersecting Families
Authors: P. Frankl, N. Tokushige
Venue: Combinatorics, Probability and Computing (1998)

Let a, b and n be integers with 2&le;a&le;b and n&ge;a+b. Suppose that &Ascr;&sub;([n]a) and &Bscr;&sub;([n]b) are nontrivial cross-intersecting families. Then &#x2223;&Ascr;&#x2223;+&#x2223;&Bscr;&#x2223;&le;2+(nb) &minus;2(n&minus;ab)+ (n&minus;2ab). This result is best possible.
On the rate of convergence of regularized boosting classifiers
Authors: Gilles Blanchard, G´bor Lugosi, Nicolas Vayatis
Venue: The Journal of Machine Learning Research (2003)

A regularized boosting method is introduced, for which regularization is obtained through a penalization function. It is shown through oracle inequalities that this method is model adaptive. The rate of convergence of the probability of misclassification is investigated. It is shown that for quite a large class of distributions, the probability of error converges to the Bayes risk at a rate faster than n-(V+2)/(4(V+1)) where V is the VC dimension of the "base" class whose elements are combined by boosting methods to obtain an aggregated classifier. The dimension-independent nature of the rates may partially explain the good behavior of these methods in practical problems. Under Tsybakov's noise condition the rate of convergence is even faster. We investigate the conditions necessary to obtain such rates for different base classes. The special case of boosting using decision stumps is studied in detail. We characterize the class of classifiers realizable by aggregating decision stumps. It is shown that some versions of boosting work especially well in high-dimensional logistic additive models. It appears that adding a limited labelling noise to the training data may in certain cases improve the convergence, as has been also suggested by other authors.
SensTec: monitoring the welfare of livestock in transit
Authors: Conor Gildea, Declan Barber, Brian Nolan
Venue: Proceedings of the 2nd international conference on Principles and practice of programming in Java (2003)

This paper describes a multi-disciplinary research project where Java is being used to combine the benefits of different sensing and communications technologies and present filtered information and alerts to agricultural analysts and supervisors. The requirement of the project is to monitor the welfare of livestock in transit from Ireland to Europe and the Middle East. The project is a joint effort between a Government Agricultural Research body and our college.
GridAnt: A Client-Controllable Grid Work.ow System
Authors: Kaizar Amin, Gregor von Laszewski, Mihael Hategan, Nestor J. Zaluzec, Shawn Hampton, Albert Rossi
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 7 - Volume 7 (2004)

Process management is an extremely important concept in both business and scientific communities. Several workflow management tools have been proposed in recent years offering advanced functionality in various domains. In the business world, workflow vendors offer commercial and customized solutions targeting specific users. In the scientific world, several open-source workflow management tools are freely available. However, they are directed toward service aggregation rather than distributed process management. Little consideration is given to the needs of the client in terms of mapping the process flow of the client. In the Grid community it is essential that the Grid users have such a tool available enabling them to orchestrate complex workflows on the fly without substantial help from the service providers. At the same time it is important that the Grid user not be burdened with the intricacies of the workflow system. With the perspective of the Grid user in mind, an extensibleclient-side workflow management system, called GridAnt, has been developed. This paper discusses the design principles, functionality, and application of the proposed GridAnt workflow manager.
Deductive database support for data visualization
Authors: Dimitra Vista
Venue: Proceedings of the 1993 conference of the Centre for Advanced Studies on Collaborative research: distributed computing - Volume 2 (1993)

We argue that we can use deductive databases to support data visualization. In particular we show how we have used the deductive languages LDL and CORAL for the implementation of the visual query language GraphLog. We discuss in detail the translation function from GraphLog to each of LDL and CORAL, especially when aggregate functions are present. We also present an example of using GraphLog and its environment Hy+ in order to support software design understanding and software design verification.
On the Density of Universal Sum-Free Sets
Authors: Tomasz Schoen
Venue: Combinatorics, Probability and Computing (1999)

A set A is called universal sum-free if, for every finite 0&ndash;1 sequence &chi; = (e1, &hellip;, en), either(i) there exist i, j, where 1&le;j<i&le;n, such that ei = ej = 1 and i &minus; j&isin;A, or(ii) there exists t&isin;N such that, for 1&le;i&le;n, we have t + i&isin;A if and only if ei = 1.It is proved that the density of each universal sum-free set is zero, which settles a problem of Cameron.
Computation and performance issues In coliseum: an immersive videoconferencing system
Authors: H. Harlyn Baker, Nina Bhatti, Donald Tanguay, Irwin Sobel, Dan Gelb, Michael E. Goss, John MacCormick, Kei Yuasa, W. Bruce Culbertson, Thomas Malzbender
Venue: Proceedings of the eleventh ACM international conference on Multimedia (2003)

Coliseum is a multiuser immersive remote teleconferencing system designed to provide collaborative workers the experience of face-to-face meetings from their desktops. Five cameras are attached to each PC display and directed at the participant. From these video streams, view synthesis methods produce arbitrary-perspective renderings of the participant and transmit them to others at interactive rates, currently about 15 frames per second. Combining these renderings in a shared synthetic environment gives the appearance of having all participants interacting in a common space. In this way, Coliseum enables users to share a virtual world, with acquired-image renderings of their appearance replacing the synthetic representations provided by more conventional avatar-populated virtual worlds. The system supports virtual mobility--participants may move around the shared space--and reciprocal gaze, and has been demonstrated in collaborative sessions of up to ten Coliseum workstations, and sessions spanning two continents. This paper summarizes the technology, and reports on issues related to its performance.
Transient simulation of large scale gas transmission networks using an adaptive method of lines
Authors: E. S. Tentis, D. P. Margaris, D. G. Papanikas
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

The modern gas pipeline distribution networks is of such scale and complexity that operate under transient conditions most of the times. The accurate and rapid prediction of the time dependent flow magnitudes is essential in order to achieve optimum cumulative deliverability and safe and reliable operation.
A methodology for the efficient architectural exploration of energy-delay trade-offs for embedded systems
Authors: L. Salvemini, M. Sami, D. Sciuto, C. Silvano, V. Zaccaria, R. Zafalon
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

The main goal of this paper is to identify the best architecture of an embedded system by considering at the same time energy and delay, avoiding the comprehensive analysis of the architectural design space. We adopt the Energy-Delay Product (EDP) as the evaluation metric to compare the alternative architectures of the target system. The paper analyzes an extended adaptive random search algorithm (ADGREED) to efficiently explore the architectural design space. The ADGREED algorithm is a pseudo-random optimisation algorithm that combines the best potentialities of the adaptive random search (ADRAS) and the Greedy deterministic algorithm. The analysis has been carried out through the architectural optimisation of the memory sub-system of a real-word embedded system executing the set of Mediabench benchmarks for multimedia applications. The reported experimental results have shown a reduction up to one order of magnitude of the number of design alternatives analyzed during the exploration phase, while maintaining very high accuracy.
Language learning and nonlinear dynamical systems
Authors: M. Spivey
Venue:  (2003)

The thesis investigates language learning. The questions that motivate this analysis include: What is language learning as a computational procedure? How can a language be learned in principle? How can a language be learned given the physical constraints of a neural system? It is believed that insight into each of these questions may be provided by an better appreciation of the capacities of nonlinear dynamical systems to learn, represent and generate complex sequential patterns and formal languages. The analysis in this thesis begins with a characterization of the problem of language learning. The concept of language learning as learning a finitely specifiable system that generates the language is described and explained. We propose and advocate the notion that nonlinear dynamical systems are legitimate examples of generative systems of language. Dynamical systems are shown to share the generative capacities of both phrase-structure grammars and discrete automata. The original research presented in this thesis begins with the investigation of the learning capacities of dynamical systems. The mathematical foundations for language learning in dynamical systems are described. It is shown how a language, in virtue of its sequential nature, can be usefully described as a type of dynamical system known as a symbolic dynamical system. It is shown that symbolic dynamical systems can be mapped directly to any member of a large class of low-dimensional chaotic dynamical systems. The importance of this is that for a given chaotic dynamical system to be a model of a given language, we may set up a target probability distribution over its state-space, such that if it visits its state-space according to this distribution it will generate the language that is desired. A specific dynamical system is chosen as a model for learning. This is known as the 2-d tent-map. We derive a learning algorithm for this particular dynamical system. This algorithm is based on a matrix approximation of the Frobenius-Perron operator. Examples of learning regular, context-free and context-sensitive languages are provided.
A video joystick from a toy
Authors: Gary Bradski, Victor Eruhimov, Sergey Molinov, Valery Mosyagin, Vadim Pisarevsky
Venue: Proceedings of the 2001 workshop on Perceptive user interfaces (2001)

The paper describes an algorithm for 3D reconstruction of a toy composed from rigid bright colored blocks with the help of a conventional video camera. The blocks are segmented using histogram thresholds and merged into one connected component corresponding to the whole toy. We also present the algorithm for extracting the color structure and matching feature points across the frames and discuss robust structure from motion and recognition connected with the subject.
The Catalan matroid
Authors: Federico Ardila
Venue: Journal of Combinatorial Theory Series A (2003)

We show how the set of Dyck paths of length 2n naturally gives rise to a matroid, which we call the "Catalan matroid" Cn. We describe this matroid in detail; among several other results, we show that Cn is self-dual, it is representable over Q but not over finite fields Fq with q ≤ n - 2, and it has a remarkably nice Tutte polynomial. We then generalize our construction to obtain a family of matroids, which we call "shifted matroids". They are precisely the matroids whose independence complex is a shifted simplicial complex.
On the Alspach Conjecture
Authors: P. N. Balister
Venue: Combinatorics, Probability and Computing (2001)

It has been conjectured by Alspach [2] that given integers n and m1, &hellip;, mt with 3 &le; mi &le; n and &sum;ti=1 mi = (n2) (n odd) or &sum;ti=1 mi = (n2) &minus; n&#x002F;2 (n even), then one can pack Kn (n odd) or Kn minus a 1-factor (n even) with cycles of lengths m1, &hellip;, mt. In this paper we show that if the cycle lengths mi are bounded by some linear function of n and n is sufficiently large then this conjecture is true.
Fitting algebraic curves to noisy data
Authors: Sanjeev Arora, Subhash Khot
Venue: Journal of Computer and System Sciences (2003)

We introduce the following problem which is motivated by applications in vision and pattern detection: We are given pairs of datapoints (x1,y1), (x2,y2),...,(xm, ym) ∈ [- 1, 1] × [- 1, 1], a noise parameter δ > 0, a degree bound d, and a threshold ρ > 0. We desire an algorithm that enlists every degree d polynomial h such that |h(xi) - yi| ≤ δ for at least δ fraction of the indices i. If δ = 0, this is just the list decoding problem that has been popular in complexity theory and for which Sudan gave a poly(m,d) time algorithm. However, for δ > 0, the problem as stated becomes ill-posed and one needs a careful reformulation (see the Introduction). We prove a few basic results about this (reformulated) problem. We show that the problem has no polynomial-time algorithm (our counterexample works for ρ = 0.5). This is shown by exhibiting an instance of the problem where the number of solutions is as large as exp(d0.5-ε) and every pair of solutions is far from each other in ℓ∞ norm. On the algorithmic side, we give a rigorous analysis of a brute force algorithm that runs in exponential time. Also, in surprising contrast to our lowerbound, we give a polynomial-time algorithm for learning the polynomials assuming the data is generated using a mixture model in which the mixing weights are "nondegenerate."
Zero-Aliasing Space Compaction of Test Responses Using a Single Periodic Output
Authors: Bhargab B. Bhattacharya, Alexej Dmitriev, Michael Gössel
Venue: IEEE Transactions on Computers (2003)

Abstract--A structure-independent method for space compaction in combinational circuits based on a new generic scheme is presented in this paper. It is shown that a single-output compactor can always be designed for compressing test responses of a circuit-under-test (CUT) with guaranteed zero-aliasing. Test responses from multiple outputs are compacted to a single periodic data stream. The compactor is independent of the fault model and can be designed only from the knowledge of the given test set and the corresponding fault-free responses. An additional response logic and a special code checker are used to design the compactor. The same test set given for the CUT also detects all multiple stuck-at faults in the response logic and almost all faults in the rest of the compactor. Further, time compaction is also easily achieved. Since the design can be accomplished without any information about the structure and functionality of the CUT, it would be useful for testing embedded cores as their internal structures may not be transparent to the users.
Estimating break points in a time series regression with structural changes
Authors: Koichi Maekawa, Zonglu He, Kianheng Tee
Venue: Mathematics and Computers in Simulation (2004)

In econometric literatures, a number of tests for unit roots have been proposed in the presence of structural changes in I(1) and I(0) model when the numbers of break points are or are not known (though their locations are unknown). Recently, Hatanaka and Yamada [A unit root test in the presence of structural changes in I(1) and I(0) models, in: R.F. Engle, H. White (Eds.), Cointegration, Causality, and Forecasting: A Festschrift in Honour of Clive W.J. Granger, Oxford University Press, Oxford, 1999 (Chapter 11)] proposed a unit root test consisted of two steps: estimating break points and testing a unit root, but their methods resulted in remarkable negative biases in the break points estimates. Our paper attempts to eliminate the negative biases by utilizing the weighted symmetric estimation.
Hybrid wavelength division multiplexing networks
Authors: Andrea Fumagalli
Venue:  (2002)

Transparency of the optical channel to transmission rate, format, and protocol is a well-known concept that has been explored in various Wavelength Division Multiplexing (WDM) all-optical networks, having subnetworks geographically separated and homogeneously designed (i.e., using same rate, protocol, and format). However, geographic boundaries of current subnetworks are becoming fuzzy, e.g., due to the introduction of virtual private networks. Moreover, the degradation of the quality of the optical signals, due to physical impairments, can affect the optical transparency even inside a subnetwork, e.g., by constraining the channel bandwidth-distance product. Also, part of the huge available bandwidth on each channel could remain unused if channels are transmitted all-optically, without the possibility of traffic aggregation at some intermediate nodes. This dissertation investigates the impact and advantages of channel transparency, in hybrid network architecture (also referred to as multi-hop architecture). The key features of hybrid networks considered in this dissertation are: multi-rate, i.e., the possibility to choose the most appropriate transmission rate on a given optical channel; and multi-span, i.e., the possibility to choose how many fibers and optical nodes the optical channel may span across transparently, before conversion of the signal from optics to electronics is required. The optimal rate and span of each optical channel is determined by a number of factors including resource availability, technology, user's application requirements, amount of multiplexed traffic, and cost effectiveness. The potential advantages provided by the Multi-Hop and Multi-Rate (M M) network when compared to first generation optical networks, to single- and multi-hop (constant single rate) optical networks, are discussed in general and demonstrated numerically for ring and mesh topologies. Also, the impact of transmission impairments&mdash;such as chromatic dispersion combined with self-phase modulation, and polarization mode dispersion&mdash;on the design and on the cost reduction in M M networks is evaluated. Results show that the network cost reduction achieved by the M M design, in the presence or absence of transmission impairments, is a function of the cost ratio between the optical bandwidth (wavelengths) and the optical terminals. The study contradicts the commonly believed fact that optical transparency is advantageous only when bandwidth is inexpensive compared to electronic processing.
Identification of graphical models for nonignorable nonresponse of binary outcomes in longitudinal studies
Authors: Wen-Qing Ma, Zhi Geng, Yong-Hua Hu
Venue: Journal of Multivariate Analysis (2003)

In this paper, we use directed acyclic graphs (DAGs) with temporal structure to describe models of nonignorable nonresponse mechanisms for binary outcomes in longitudinal studies, and we discuss identification of these models under an assumption that the sequence of variables has the first-order Markov dependence, that is, the future variables are independent of the past variables conditional on the present variables. We give a stepwise approach for checking identifiability of DAG models. For an unidentifiable model, we propose adding completely observed variables such that this model becomes identifiable.