ppxscal/embedding_network huggingface dataset:
Confidentiality via Camouflage: The CVC Approach to Disclosure Limitation When Answering Queries to Databases
Authors: Ram Gopal, Robert Garfinkel, Paulo Goes
Venue: Operations Research (2002)

A practical method is presented for giving unlimited, deterministically correct, numerical responses to ad-hoc queries to an online database, while not compromising confidential numerical data. The method is appropriate for any size database, and no assumptions are needed about the statistical distribution of the confidential data. Responses are in the form of a number plus a guarantee, so the user can determine an interval that is sure to contain the exact answer. Virtually any imaginable query type can be answered, and in the absence of insider information, collusion among the users presents no problem. Experimental analysis supports the practical viability of the proposed method.
On dominance and dispersion of a class of weighting lists
Authors: Tomasa Calvo, Javier Martín, Gaspar Mayor, Jaume Suñer
Venue: Technologies for constructing intelligent systems: tools (2002)

The class of weighting lists with a prefixed minimum and maximum values is studied. It is introduced the concept of degree of Dominance of a weighting list as a generalization of the degree of Orness. It is proved that, with good conditions, there always exist two unique lists with minimum and maximum dominance respectively. From the concepts of dominance and dispersion, it is solved the problem of obtaining the weighting list in the class considered here of maximum dispersion with a given degree of dominance.
Global attractivity in the recursive sequence xn+1= (α - βxn)/(γ - xn-1)
Authors: Xing-Xue Yan, Wan-Tong Li
Venue: Applied Mathematics and Computation (2003)

Our aim in this paper is to investigate the global attractivity of the recursive sequence xn+1 = α - βxn/γ - xn-1, n = 0,1,..., where α ≥ 0, β, γ > 0. We show that one positive equilibrium point of the equation is a global attractor with a basin that depends on certain conditions posed on the coefficients.
Five properties of the Smarandache double factorial function
Authors: Felice Russo
Venue: Smarandache notions (2002)

In this paper some properties of the Smarandache double factorial function have been analyzed.
Abstractions from time
Authors: Manfred Broy
Venue: Programming methodology (2003)

Mathematical models of the timed behaviour of system components form a hierarchy of timing concepts. This is demonstrated for systems that communicate via input and output streams. We distinguish non-timed streams, discrete streams with discrete and with continuous time, and dense streams with continuous time. We demonstrate how exchanges of the timing models during the system-development process are captured as classical abstraction steps.
Stocking Retail Assortments Under Dynamic Consumer Substitution
Authors: Siddharth Mahajan, Garrett van Ryzin
Venue: Operations Research (2001)

We analyze a single-period, stochastic inventory model (newsboy-like model) in which a sequence of heterogeneous customers dynamically substitute among product variants within a retail assortment when inventory is depleted. The customer choice decisions are based on a natural and classical utility maximization criterion. Faced with such substitution behavior, the retailer must choose initial inventory levels for the assortment to maximize expected profits.Using a sample path analysis, we analyze structural properties of the expected profit function. We show that, under very general assumptions on the demand process, total sales of each product are concave in their own inventory levels and possess the so-calleddecreasing differences property, meaning that the marginal value of an additional unit of the given product is decreasing in the inventory levels of all other products. For a continuous relaxation of the problem, we then show, via counterexamples, that the expected profit function is in general not even quasiconcave. Thus, global optimization may be difficult. However, we propose and analyze a stochastic gradient algorithm for the problem, and prove that it converges to a stationary point of the expected profit function under mild conditions. Finally, we apply the algorithm to a set of numerical examples and compare the resulting inventory decisions to those of some simpler, naive heuristics. The examples show that substitution effects can have a significant impact on an assortment's gross profits. The examples also illustrate some systematic distortions in inventory decisions if substitution effects are ignored. In particular, under substitution one should stock relatively more of popular variants and relatively less of unpopular variants than a traditional newsboy analysis indicates.
Or Modeling and Aids Policy: From Theory to Practice
Authors: James G. Kahn, Margaret L. Brandeau, John Dunn-Mortimer
Venue: Interfaces (1998)

The AIDS epidemic is a serious, growing public health problem worldwide, but resources for treating HIV-infected patients and for combating the spread of the virus are limited. Governments, public-health agencies, and healthcare providers must determine how best to allocate scarce resources for HIV treatment and prevention among different programs and populations. OR-based models have influenced-and can influence-AIDS policy decisions. Mathematical modeling has had an effect on AIDS policy in a number of areas, including estimating HIV prevalence and incidence in the United States, understanding the pathophysiology of HIV, evaluating costs and benefits of HIV-screening programs, evaluating the effects of needle-exchange programs, and determining policies for HIV/AIDS care in California. Further work is needed to model a range of programs using comparable methods, to model overall epidemic control strategy, and to improve the usefulness of OR-based models for policy making.
Perceived Influences on Implementing Data Warehousing
Authors: Robert Grover Little, Michael Lucas Gibson
Venue: IEEE Transactions on Software Engineering (2003)

This study surveyed data warehousing implementation project participants to determine what aspects they perceived should contribute to the implementation process. The respondents included: functional managers/staff, IS managers/staff, and consultants. The study identified eight significant factors that participants perceived should impact data warehouse implementation.
Methodology used for "Software for automated linkage in Italy" (SALI)
Authors: Luigino Dal Maso, Claudia Braga, Silvia Franceschi
Venue: Computers and Biomedical Research (2001)

Linkage of epidemiological registries can provide cost-effective information on the associations between different diseases or exposures in the population under study and on completeness of surveillance system databases. We describe the program SALI (software for automated linkage in Italy) aimed at matching individual records from medium-sized registries (in the order of 100,000 records), where the desired outcome is to miss as few links as possible and, because of low link-likelihood (>1%), a manual revision of matched pairs is feasible. SALI, developed in CA-Clipper language, uses registry files in dBase format. It requires only name, surname, and date of birth as key fields, and it allows for spelling errors in Italian or other Latin languages through a specific algorithm. Furthermore, a double-blind procedure ensures data confidentiality. The main linkage procedure is based on four stages, two automatic ones, and two where the operator can decide through specific windows whether to accept stage-selected matches. SALI takes into account possible errors in key fields thus reducing false negatives. It was used to solve the problem of linkage between AIDS and cancer registries in Italy. It can be used with every IBM-compatible computer system, assuring uniquely high portability.
Spectral properties of Jacobi matrices by asymptotic analysis
Authors: Jan Janas, Marcin Moszyński
Venue: Journal of Approximation Theory (2003)

We consider two classes of Jacobi matrix operators in l2 with zero diagonals and with weights of the form nα + cn for 0 < α ≤ 1 or of the form nα + cnnα-1 for α > 1, where {cn} is periodic. We study spectral properties of these operators (especially for even periods), and we find asymptotics of some of their generalized eigensolutions. This analysis is based on some discrete versions of the Levinson theorem, which are also proved in the paper and may be of independent interest.
Path Dependence, Competition, and Succession in the Dynamics of Scientific Revolution
Authors: John D. Sterman, Jason Wittenberg
Venue: Organization Science (1999)

What is the relative importance of structural versus contextual forces in the birth and death of scientific theories? We describe a formal dynamic model of the birth, evolution, and death of scientific paradigms based on Kuhn's Structure of Scientific Revolutions. The model represents scientific activity as a changing set of coupled institutions; a simulated ecology of interacting paradigms in which the creation of new theories is stochastic and endogenous. The model captures the sociological dynamics of paradigms as they compete against one another for members, solve puzzles, and recognize anomalies. We use sensitivity tests and regression to examine the role of intrinsic versus contextual factors in determining paradigm success. We find that situational factors attending the birth of a paradigm largely determine its probability of rising to dominance, while the intrinsic explanatory power of a paradigm is only weakly relatedto the likelihood of success. For those paradigms surviving the emergence phase, greater explanatory power is significantly related to longevity. However, the relationship between a paradigm's "strength" and the duration of normal science is also contingent on the competitive environment during the emergence phase. Analysis of the model shows the dynamics of competition and succession among paradigms to be conditioned by many positive feedback loops. These self-reinforcing processes amplify intrinsically unobservable microlevel perturbations in the environment-the local conditions of science, society, and self faced by the creators of a new theory-until they reach macroscopic significance. Such path dependent dynamics are the hallmark of self-organizing evolutionary systems. We consider the implications of these results for the rise and fall of new ideas in contexts outside the natural sciences such as management fads.
Subset Comparisons for Additive Linear Orders
Authors: Peter C. Fishburn, Aleksandar Pekec, James A Reed
Venue: Mathematics of Operations Research (2002)

This paper investigates algebraic and combinatorial properties of the set of linear orders on the algebra of subsets of a finite set that are representable by positive measures. It is motivated by topics in decision theory and the theory of measurement, where an understanding of such properties can facilitate the design of strategies to elicit comparisons between subsets that, for example, determine an individual's preference order over subsets of objects or an individual's qualitative probability order over subsets of states of the world. We introduce a notion of critical pairs of binary comparisons for such orders and prove that (i) each order is uniquely characterized by its set of critical pairs and (ii) the smallest set of binary comparisons that determines an order is a subset of its set of critical pairs. The paper then focuses on the minimum number of on-line binary-comparison queries between subsets that suffice to determine any representable order for a set of given cardinalityn. It is observed that, for smalln, the minimum is attained by first determining the ordering of singleton subsets. We also consider query procedures with fixed numbers of stages, in each stage of which a number of queries for the next stage are formulated.
Integrating Wireless LAN and Cellular Data for the Enterprise
Authors: Hui Luo, Zhimei Jiang, Byoung-Jo Kim, N. K. Shankaranarayanan, Paul Henry
Venue: IEEE Internet Computing (2003)

The Internet Roaming solution for corporate wireless data users integrates mobile networking across private WLANs, public WLANs, and cellular data networks.
xTask - Adaptable Working Environment
Authors: Harri Ketamo
Venue: Proceedings IEEE International Workshop on Wireless and Mobile Technologies in Education (2002)

Traditional web-based learning environments are all good solutions to reach the time and place independent studying, but studying is still dependent on place with access to network. With new mobile technologies we can create the training environment, which can be accessed by mobile terminals (PDA's such as Compaq iPaq or WAP phones) and PC's.This paper describes a study which aim was to implement mobile environment, xTask, for teaching and training. The xTask can be accessed by PC's or PDA's and it is build over free software platforms (such as Apache web -server, ActivePerl programming interface and MySql database). Free software platforms are utilized to make possible anyone to use xTask after themain parts of the software are published at the end of 2002 under GPL license.
Shaping web usability: interaction design in context
Authors: Albert N. Badre
Venue: Ubiquity (2002)

Optimizing the user experience should be the ultimate aim of the Web usability designer.
Median correlation for the analysis of gene expression data
Authors: Karen M. Bloch, Gonzalo R. Arce
Venue: Signal Processing (2003)

Microarray technology is revolutionizing functional genomics research by allowing scientists to measure the expression level of thousands of genes simultaneously from a single sample. However, a standard protocol for microarray data analysis has yet to be established. Many analysis techniques currently rely on linear correlation between pairs of genes. Such analysis only detects relationships in signal components exhibiting Gaussian correlation statistics. This paper focuses on determining the relationships between gene patterns based on a hierarchical clustering of nonlinear correlation measurements. The methods described herein are illustrated with gene expression data from yeast, and from human cancer cell lines. The results indicate that in some cases, improved clustering of genes can be achieved by the use of nonlinear correlation metrics.
Almost-certain eventualities and abstract probabilities in the quantitative temporal logic qTL
Authors: Annabelle McIver, Carroll Morgan
Venue: Theoretical Computer Science (2003)

'Almost-certain eventualities' are liveness properties that hold with probability 1. 'Abstract probabilities' in transition systems are those known only to be bounded away from zero and one.Vardi (Proceedings of the 26th IEEE Symposium on Foundations of Computer Science, Portland, 1985, p. 327) showed that almost-certain properties in linear temporal logic depend only on abstract probabilities rather than on the probabilities' precise values. We discuss the extent to which a similar result holds in the quantitative temporal logic qTL derived from the quantitative modal µ,calculus qMµ (Proceedings the Formal Methods Pacific '97, Springer, Singapore, 1997, also available http://web.comlab.ox.ac.uk/oucl/research/areas/probs/bibliography.html; logic J, IGPL 7(6) (1999) 779, http://www3.oup.co.uk/igpl/Volume_07/Issue_06, http://web.comlab. ox.ac.uk/oucl/research/areas/probs/bibliography.html), and we show how to specialise the logic to these cases. The aim is to provide a simpler calculus than the full logic, one that is in a certain sense complete for proving almost-certain eventualities from abstract-probabilistic assumptions.We concinde by considering the complexity of the specialised logic.
An object framework for teaching ALU component design in architecture courses
Authors: Norman Neff, G. Sampath
Venue: Journal of Computing Sciences in Colleges (2003)

An object-based framework for teaching the design of ALU components in a computer architecture course is described. An object-oriented pseudocode description of the component's behavior is developed and then transformed into an implementation. The pseudocode represents subcomponents as objects, and relationships between subcomponents as constraint sets. A hardware implementation of the pseudocode is created by mapping objects to subcomponents and constraints to connections, and by a standard hardware implementation of the pseudocode program counter. In many applications, our framework gives to the hardware design process desirable characteristics of object-oriented software design: modularity, hierarchical design, and control over the level of abstraction. Our pseudocode notation makes explicit some of the underlying "intuition" guiding the design process. In the software realm we all teach students to create code only after completing a thorough design phase. Our approach to hardware design similarly shifts much of the process from the lab to an earlier, language-based design stage.
Direction Choice for Accelerated Convergence in Hit-And-Run Sampling
Authors: David E. Kaufman, Robert L. Smith
Venue: Operations Research (1998)

Hit-and-Run algorithms are Monte Carlo procedures for generating points that are asymptotically distributed according to general absolutely continuous target distributions G over open bounded regions S. Applications include nonredundant constraint identification, global optimization, and Monte Carlo integration. These algorithms are reversible random walks that commonly incorporate uniformly distributed step directions. We investigate nonuniform direction choice and show that, under regularity conditions on the region S and target distribution G, there exists a unique direction choice distribution, characterized by necessary and sufficient conditions depending on S and G, which optimizes the Doob bound on rate of convergence. We include computational results demonstrating greatly accelerated convergence for this optimizing direction choice as well as for more easily implemented adaptive heuristic rules.
Learning the Statistics of People in Images and Video
Authors: Hedvig Sidenbladh, Michael J. Black
Venue: International Journal of Computer Vision (2003)

This paper address the problems of modeling the appearance of humans and distinguishing human appearance from the appearance of general scenes. We seek a model of appearance and motion that is generic in that it accounts for the ways in which people's appearance varies and, at the same time, is specific enough to be useful for tracking people in natural scenes. Given a 3D model of the person projected into an image we model the likelihood of observing various image cues conditioned on the predicted locations and orientations of the limbs. These cues are taken to be steered filter responses corresponding to edges, ridges, and motion-compensated temporal differences. Motivated by work on the statistics of natural scenes, the statistics of these filter responses for human limbs are learned from training images containing hand-labeled limb regions. Similarly, the statistics of the filter responses in general scenes are learned to define a &ldquo;background&rdquo; distribution. The likelihood of observing a scene given a predicted pose of a person is computed, for each limb, using the likelihood ratio between the learned foreground (person) and background distributions. Adopting a Bayesian formulation allows cues to be combined in a principled way. Furthermore, the use of learned distributions obviates the need for hand-tuned image noise models and thresholds. The paper provides a detailed analysis of the statistics of how people appear in scenes and provides a connection between work on natural image statistics and the Bayesian tracking of people.
Analysis of a discrete-time GI-G-1 queueing model subjected to bursty interruptions
Authors: Dieter Fiems, Bart Steyaert, Herwig Bruneel
Venue: Computers and Operations Research (2003)

In this contribution, we investigate a discrete-time single-server queue subjected to server interruptions generated by a 2-state Markov process. The model under consideration assumes customers with multiple-slot service times, which leads to the introduction of two different service strategies depending on whether service of an interrupted customer continues or restarts after an interruption. For both alternatives, we establish expressions for the steady-state probability generating functions of the buffer contents, the unfinished work and the customer delay in terms of the effective customer service times. From these results, closed-form expressions for various performance measures, such as the moments of these quantities, can be established. After dealing with some stability issues, we illustrate the impact of both service strategies on the buffer performance with some numerical examples.
A negative answer to T. Kubiak's question
Authors: Sanjiang Li, Maokang Luo
Venue: Fuzzy Sets and Systems (2003)

T. Kubiak raised in 1992 a question about Hausdorffness and compactness in L-topology. It is negatively solved in the present paper by constructing certain L-Hausdorffness and L-compactness axioms.
Combine concept of agent and service to build distributed object-oriented system
Authors: Chunlin Li, Layuan Li
Venue: Future Generation Computer Systems (2003)

This paper presents a Java-based agent-oriented and service-oriented environment, which combines the concept of services and agents to build distributed object-oriented system. Mobile agents are often subject to strong security restrictions, they should find services that help complete their tasks. Services are wrapped by service interface agents. This paper mainly describes how mobile agents locate specific service interface agent by submitting requests to the service server with descriptions of required services in the network, and how service interface agents dynamically register their services in service server. Finally, some conclusions are given.
Distributed PIN verification scheme for improving security of mobile devices
Authors: Jian Tang, Vagan Terziyan, Jari Veijalainen
Venue: Mobile Networks and Applications (2003)

The main driving force for the rapid acceptance rate of small sized mobile devices is the capability to perform e-commerce transactions at any time and at any place, especially while on the move. There are, however, also weaknesses of this type of e-commerce, often called mobile e-commerce, or m-commerce. Due to their small size and easy portability mobile devices can easily be lost or stolen. Whereas the economic values and privacy threats protected with Personal Identification Numbers (PIN) are not particularly high for normal voice-enabled mobile phones, this is not true any more when phones have developed to Personal Trusted Devices (PTDs). Still, PINs are used also in this new context for authorization and identification purposes. PINs are currently used both for protection of the devices and for authentication, as well as authorization of the users. It is commonly recognized that not many techniques of storing the PINs into the memory of the device or on the SIM card are safe. Even less sophisticated thieves might uncover the PIN inside the stolen mobile devices and for sophisticated thieves uncovering the PIN stored "safely" might be possible. In this paper we propose a new scheme to cope with the problem of uncovering the PIN that reduces the risks of m-commerce. The basic idea is that instead of storing the entire PIN digits (or some hash value) in the mobile device, we store part of the PIN in a remote machine in the network. The PIN verification then involves both the mobile device and the remote machine, which must verify their respective parts of the PIN. Also, the improvements of the security over the existing schemes are shown using a probabilistic model. In the best case, where the probability of discovering the PIN irrespective of the storage scheme is negligible in relation to directly uncovering it, the increase in security is over 1000%.