pinecone/core-2020-05-10-deduplication huggingface dataset:
A Java Middleware for Guaranteeing Privacy of Distributed Tuple Spaces

The tuple space communication model, such as the one used in Linda, provides great flexibility for modeling concurrent, distributed and mobile processes. In a distributed setting with mobile agents, particular attention is needed for protecting sites and information. We have designed and developed a Java middleware, Klava, for implementing distributed tuple spaces and operations to support agent interaction and mobility. In this paper, we extend the Klava middleware with cryptographic primitives that enable encryption and decryption of tuple fields. We describe the actual implementation of the new primitives and provide a few examples. The proposed extension is general enough to be applied to similar Java frameworks using multiple distributed tuples spaces possibly dealing with mobility
Static scheduling with interruption costs for computer vision applications

It is very difficult to find pre-emptive scheduling algorithms that
consider all the main characteristics of computer vision systems. Moreover,
there is no generic algorithm that considers interruption costs for such systems.
Taking the interruption of tasks into account scheduling results can be
improved. But it is also very important to take the costs that arise from
interruptions into account because they not only increase the total execution
time, but also because the scheduler can evaluate whether it is adequate to
interrupt certain tasks or not. Thus, the result can be more realistic. Therefore,
we present an extension to the static algorithm SASEPA for computer vision
which considers interruption costs
Wavelet transform for large scale image processing on modern microprocessors

In this paper we discuss several issues relevant to the vectorization of a 2-D Discrete Wavelet Transform on current microprocessors. Our research is based on previous studies about the efficient exploitation of the memory hierarchy, due to its tremendous impact on performance. We have extended this work with a more detailed analysis based on hardware performance counters and a study of vectorization, in particular, we have used the Intel Pentium SSE instruction set. Most of our optimizations are performed at source code level to allow automatic vectorization, though some compiler intrinsic functions have been introduced to enhance performance. Taking into account the abstraction at which the optimizations are performed, the results obtained on an Intel Pentium III microprocessor are quite satisfactory, even though further improvement can be obtained by a more extensive use of compiler intrinsics
Genetic algorithms for the generation of models with micropopulations

Proceedings of: EvoWorkshops 2003: EvoBIO, EvoCOP, EvoIASP, EvoMUSART, EvoROB, and EvoSTIM Essex, UK, April 14–16, 2003The present article puts forward a method for an interactive model generation through the use of Genetic Algorithms applied to small populations. Micropopulations actually worsen the problem of the premature convergence of the algorithm, since genetic diversity is very limited. In addition, some key factors, which modify the changing likelihood of alleles, cause the likelihood of premature convergence to decrease. The present technique has been applied to the design of 3D models, starting from generic and standard pieces, using objective searches and searches with no defined objective
Phase transitions and stochastic local search in k-term DNF learning

In the past decade, there has been a lot of interest in phase transitions within artificial intelligence and more recently, in machine learning and inductive logic programming. We investigate phase transitions in learning k-term DNF boolean formulae, a practically relevant class of concepts. We do not only show that, there exist phase transitions, but also characterize and locate these phase transitions using the parameters k, the number of positive and negative examples, and the number of boolean variables. Subsequently, we investigate stochastic local search (SLS) for k-term DNF learning. We compare several variants that first reduce k-term DNF to SAT and then apply well-known SLS algorithms, such as GSAT and WalkSAT. Our experiments indicate that WalkSAT is able to solve the largest fraction of hard problem instances.status: publishe
Ranking with predictive clustering trees

A novel class of applications of predictive clustering trees is addressed, namely ranking. Predictive clustering trees, as implemented in Clus, allow for predicting multiple target variables. This approach makes sense especially if the target variables are not independent of each other. This is typically the case in ranking, where the (relative) performance of several approaches on the same task has to be predicted from a given description of the task. We propose to use predictive clustering trees for ranking. As compared to existing ranking approaches which are instance-based, our approach also allows for an explanation of the predicted rankings. We illustrate our approach on the task of ranking machine learning algorithms, where the (relative) performance of the learning algorithms on a dataset has to be predicted from a given dataset description.status: publishe
A commit scheduler for XML databases

The hierarchical and semistructured nature of XML data\ud
may cause complicated update-behavior. Updates should not be limited to entire document trees, but should ideally involve subtrees and even individual elements. Providing a suitable scheduling algorithm for semistructured data can signicantly improve collaboration systems that store their data | e.g. word processing documents or vector graphics | as XML documents. In this paper we improve upon earlier work (see [5]) which presented two equivalent concurrency control mechanisms based on Path Locks. In contrast to the earlier work, we now provide details regarding the workings of a commit scheduler for XML databases which uses the path lock conflict rules. We also give a comprehensive proof\ud
of serializability which enhances and claries the ideas in our previous work
Trade-off between performance and robustness: An evolutionary multiobjective approach

In real-world applications, it is often desired that a solution is not only of high performance, but also of high robustness. In this context, a solution is usually called robust, if its performance only gradually decreases when design variables or environmental parameters are varied within a certain range. In evolutionary optimization, robust optimal solutions are usually obtained by averaging the fitness over such variations. Frequently, maximization of the performance and increase of the robustness are two conflicting objectives, which means that a trade-off exists between robustness and performance. Using the existing methods to search for robust solutions, this trade-off is hidden and predefined in the averaging rules. Thus, only one solution can be obtained. In this paper, we treat the problem explicitly as a multiobjective optimization task, thereby clearly identifying the trade-off between performance and robustness in the form of the obtained Pareto front. We suggest two methods for estimating the robustness of a solution by exploiting the information available in the current population of the evolutionary algorithm, without any additional fitness evaluations. The estimated robustness is then used as an additional objective in optimization. Finally, the possibility of using this method for detecting multiple optima of multimodal functions is briefly discussed. © Springer-Verlag Berlin Heidelberg 2003
Smart Sketch System for 3D Reconstruction Based Modeling

Current user interfaces of CAD systems are still not suited to the initial
 stages of product development, where freehand drawings are used by engineers
 and designers to express their visual thinking. In order to exploit these
 sketching skills, we present a sketch based modeling system, which provides a
 reduced instruction set calligraphic interface to create orthogonal polyhedra, and
 an extension of them we named quasi-normalons. Our system allows users to
 draw lines on free-hand axonometric-like drawings, which are automatically tidied
 and beautified. These line drawings are then converted into a threedimensional
 model in real time because we implemented a fast reconstruction
 process, suited for quasi-normalon objects and so-called axonometric inflation
 method, providing in this way an innovative integrated 2D sketching and 3D
 view visualization work environment.This work was supported in part by the Portuguese Science
Foundation grant 34672/99, the European Commission project IST-2000-28169, the
Spanish Generalidad Valenciana grant CTIDIB/2002/51 and Fundació Caixa Castelló-
Bancaixa under the Universitat Jaume I program for Research Promotion (Project P1-
1B2002-08)
Spin in quantum field theory

I introduce spin in field theory by emphasizing the close connection between
quantum field theory and quantum mechanics. First, I show that the
spin-statistics connection can be derived in quantum mechanics without
relativity or field theory. Then, I discuss path integrals for spin without
using spinors. Finally, I show how spin can be quantized in a path-integral
approach, without introducing anticommuting variables.Comment: 31 pages, 6 figures, latex with Springer svmult document class; typos
  corrected, refs 10-11 adde
Performance evaluation of DiffServ driven HFC system

Shared access networks such as hybrid fiber/coaxial and passive optical networks have emerged as promising ways to reduce the cost of the transition to a broadband access infrastructure and provide a graceful upgrade path towards the photonization of the local loop. The MAC protocol as the only arbiter of the upstream bandwidth directly affects the Quality of Service (QoS) provided to each upstream traffic flow and must meet several constraints. Such constraints include the adequate speed of operation, flexibility to support efficiently the largest number of services and applications offering an adequate number of QoS classes, and independence of higher layers, protocols and future extensions to traffic management specifications. The implementation of a MAC mechanism targeting these goals and aligned to the emerging Differentiated Services Internet strategy is evaluated using computer simulation results in this paper. The benefits of the adopted prioritization scheme to provide and guarantee different QoS levels are illustrated
Convergence of IP-based and optical transport networks

Today Network and Service Providers are aware of the increasing data traffic volumes and as such they are strategically moving investigations toward a single integrated voice and data infrastructure. In this context IP is gaining the role of the integration layer for multiple services. Nevetheless incumbent NSPs that build a multi-service IP network are going to need connectivity to its preexisting legacy networks (e.g. ATM. SONET, SDH). This reason motivates the introduction of a client-independent Optical Transport Network (OTN) as a missing link to guarantee a smooth evolution from legacy networks to a data-centric OTN. The scope of this paper is to give some guidelines about the definition of functionality and architectures of a multilayers infrastructure supporting the transport of data and circuit-based services. Particularly, the identification of the different service requirements, as well as the understanding of the allowed degradation, provide a picture of the needed survivability mechanism of IP over OTN scenarios
Provision of QoS for legacy IP applications in an ATM-over-HFC access network

With the increasing needs for delivering higher bandwidths to residential areas, new technologies (e.g. xDSL) are emerging that are enabling broadband access. Network technologies, which are based upon upgrades of existing network infrastructures, are, economically, one of the most promising approaches. One of these, competing with several other approaches, is hybrid fibre coax networks (HFC) currently being used for CATV broadcasting. The various access network technologies will be interconnected via broadband core networks resulting in heterogeneous networks which, have to provide end-to-end applications based on the Internet Protocol. Since the CATV network is of a shared nature, the provisioning of IP-based Quality of Service (QoS) requires suitable inter-laver signalling in order to provide QoS-related information as soon as possible to the relevant instances. This paper presents a system architecture using ATM-over-HFC for high-speed Internet access providing IP-based QoS. The architecture's seamless interoperability with other network technologies supports both IP-based and native ATM applications
Design of a multi-layer Bandwidth Broker architecture

Internet is widely known lbr lacking any kind or mechanism for the provisioning OF Quality of Service guarantees. The Internet community concentrates its efforts on the Bandwidth Broker architecture towards this problem. This paper presents a design model of a multi-layer Bandwidth Broker architecture that introduces a Resource Control Layer, which is divided into two sub-layers. The upper one is responsible for the overall network administration, while the lower one performs per-flow policy-based admission control. The design models, the mechanisms, and algorithms adopted in this architecture will be delineated
Seamless and uninterrupted interworking of wireless and wireline network technologies

The Internet Protocol (IP) dominates in today's data communication infrastructures. The network evolution also favors the explosion of the wireless network technologies. The latter have to be combined and interoperate properly with current wireline installations. Although IP assures interoperability, there are open interworking issues at the session, network, and data link layers related to the nature of the wireless environment. The architecture presented in this paper, proposes specific enhancements to an IP infrastructure, that alleviate the deficiencies of wireless networks and propel the efficient interworking between wireline and wireless network technologies
Performance of active multicast congestion control

This paper aims to provide insight into the behavior of congestion control mechanisms for reliable multicast protocols. A multicast congestion control based on active networks has been proposed and simulated using ns-2 over a network topology obtained using the Tiers tool. The congestion control mechanism has been simulated under different network conditions and with different settings of its configuration parameters. The objective is to analyze its performance and the impact of the different configuration parameters on its behavior. The simulation results show that the performance of the protocol is good in terms of delay and bandwidth utilization. The compatibility of the protocol with TCP flows has not been demonstrated, but the simulations performed show that by altering the parameter settings, the proportion of total bandwidth taken up by the two types of flow, multicast and TCP, may be modified.Publicad
Principles of Equivalence: Their Role in Gravitation Physics and
  Experiments that Test Them

Modern formulations of equivalence principles provide the foundation for an
efficient approach to understanding and organizing the structural features of
gravitation field theories. Since theories' predictions reflect differences in
their structures, principles of equivalence also support an efficient
experimental strategy for testing gravitation theories and for exploring the
range of conceivable gravitation physics. These principles focus attention
squarely on empirical consequences of the fundamental structural differences
that distinguish one gravitation theory from another. Interestingly, the
variety of such consequences makes it possible to design and perform
experiments that test equivalence principles stringently but do so in markedly
different ways than the most familiar experimental tests.Comment: in: ''Gyros, Clocks, and Interferometers...: Testing Relativistic
  Gravity in Space'' (C. L\"ammerzahl, C.W.F. Everitt, F.W. Hehl eds.),
  Springer-Verlag 200
Searching for Extra Dimensions and New String-Inspired Forces in the
  Casimir Regime

The appearance of new fundamental forces and extra-dimensional modifications
to gravity in extensions of the Standard Model has motivated considerable
interest in testing Newtonian gravity at short distances (<10^-3 m). Presently
a number of new gravity experiments are searching for non-Newtonian effects in
the ranges 10^-4 m -- 10^-3 m. However, as challenging as these experiments
are, formidable new obstacles await the next generation of experiments which
will probe gravity at distances <10^-4 m where Casimir/van der Waals forces
become dominant. Here we will review the motivation for conducting such very
short distance gravity experiments, and discuss some of the new problems that
may arise in future experiments. Finally, we suggest schematic designs for null
experiments which would address some of these problems using the
``iso-electronic'' and ``finite-size'' effects.Comment: 16 pages, 6 figures, LaTeX, (uses cite.sty), will appear in "Testing
  General Relativity in Space: Gyroscopes, Clocks, and Interferometers," edited
  by C. L\"ammerzahl, C. W. F. Everitt, F. W. Hehl (Springer-Verlag, 2000);
  replaced with slight revision which adds an additional reference and updates
  another referenc
Relativistic phase shifts for Dirac particles interacting with weak
  gravitational fields in matter-wave interferometers

We present a second-quantized field theory of massive spin one-half particles
or antiparticles in the presence of a weak gravitational field treated as a
spin two external field in a flat Minkowski background. We solve the
difficulties which arise from the derivative coupling and we are able to
introduce an interaction picture. We derive expressions for the scattering
amplitude and for the outgoing spinor to first-order. In several appendices,
the link with the canonical approach in General Relativity is established and a
generalized stationary phase method is used to calculate the outgoing spinor.
We show how our expressions can be used to calculate and discuss phase shifts
in the context of matter-wave interferometry (especially atom or antiatom
interferometry). In this way, many effects are introduced in a unified
relativistic framework, including spin-gravitation terms: gravitational red
shift, Thomas precession, Sagnac effect, spin-rotation effect, orbital and spin
Lense-Thirring effects, de Sitter geodetic precession and finally the effect of
gravitational waves. A new analogy with the electromagnetic interaction is
pointed out.Comment: 32 pages, LaTex, needs rotating and lscape usepackages, to appear in
  C. L\"ammerzahl, C.W.F. Everitt, F.W. Hehl (eds.): ``Gyros, Clocks, and
  Interferometers: Testing Relativistic Gravity in Space'', Springer-Verlag,
  Berlin 200
Testing the Dirac equation

The dynamical equations which are basic for the description of the dynamics
of quantum felds in arbitrary space--time geometries, can be derived from the
requirements of a unique deterministic evolution of the quantum fields, the
superposition principle, a finite propagation speed, and probability
conservation. We suggest and describe observations and experiments which are
able to test the unique deterministic evolution and analyze given experimental
data from which restrictions of anomalous terms violating this basic principle
can be concluded. One important point is, that such anomalous terms are
predicted from loop gravity as well as from string theories. Most accurate data
can be obtained from future astrophysical observations. Also, laboratory tests
like spectroscopy give constraints on the anomalous terms.Comment: 11 pages. to appear in: C. L\"ammerzahl, C.W.F. Everitt, and F.W.
  Hehl (eds.): Gyros, Clocks, Interferometers...: Testing Relativistic Gravity
  in Space, Lecture Notes in Physics 562, Springer 200
How does the electromagnetic field couple to gravity, in particular to
  metric, nonmetricity, torsion, and curvature?

The coupling of the electromagnetic field to gravity is an age-old problem.
Presently, there is a resurgence of interest in it, mainly for two reasons: (i)
Experimental investigations are under way with ever increasing precision, be it
in the laboratory or by observing outer space. (ii) One desires to test out
alternatives to Einstein's gravitational theory, in particular those of a
gauge-theoretical nature, like Einstein-Cartan theory or metric-affine gravity.
A clean discussion requires a reflection on the foundations of electrodynamics.
If one bases electrodynamics on the conservation laws of electric charge and
magnetic flux, one finds Maxwell's equations expressed in terms of the
excitation H=(D,H) and the field strength F=(E,B) without any intervention of
the metric or the linear connection of spacetime. In other words, there is
still no coupling to gravity. Only the constitutive law H= functional(F)
mediates such a coupling. We discuss the different ways of how metric,
nonmetricity, torsion, and curvature can come into play here. Along the way, we
touch on non-local laws (Mashhoon), non-linear ones (Born-Infeld,
Heisenberg-Euler, Plebanski), linear ones, including the Abelian axion (Ni),
and find a method for deriving the metric from linear electrodynamics (Toupin,
Schoenberg). Finally, we discuss possible non-minimal coupling schemes.Comment: Latex2e, 26 pages. Contribution to "Testing Relativistic Gravity in
  Space: Gyroscopes, Clocks, Interferometers ...", Proceedings of the 220th
  Heraeus-Seminar, 22 - 27 August 1999 in Bad Honnef, C. Laemmerzahl et al.
  (eds.). Springer, Berlin (2000) to be published (Revised version uses
  Springer Latex macros; Sec. 6 substantially rewritten; appendices removed;
  the list of references updated
Gravitomagnetism and the Clock Effect

The main theoretical aspects of gravitomagnetism are reviewed. It is shown
that the gravitomagnetic precession of a gyroscope is intimately connected with
the special temporal structure around a rotating mass that is revealed by the
gravitomagnetic clock effect. This remarkable effect, which involves the
difference in the proper periods of a standard clock in prograde and retrograde
circular geodesic orbits around a rotating mass, is discussed in detail. The
implications of this effect for the notion of ``inertial dragging'' in the
general theory of relativity are presented. The theory of the clock effect is
developed within the PPN framework and the possibility of measuring it via
spaceborne clocks is examined.Comment: 27 pages, LaTeX, submitted to Proc. Bad Honnef Meeting on: GYROS,
  CLOCKS, AND INTERFEROMETERS: TESTING GENERAL RELATIVITY IN SPACE (22 - 27
  August 1999; Bad Honnef, Germany
Gravitational Radiation Theory and Light Propagation

The paper gives an introduction to the gravitational radiation theory of
isolated sources and to the propagation properties of light rays in radiative
gravitational fields. It presents a theoretical study of the generation,
propagation, back-reaction, and detection of gravitational waves from
astrophysical sources. After reviewing the various quadrupole-moment laws for
gravitational radiation in the Newtonian approximation, we show how to
incorporate post-Newtonian corrections into the source multipole moments, the
radiative multipole moments at infinity, and the back-reaction potentials. We
further treat the light propagation in the linearized gravitational field
outside a gravitational wave emitting source. The effects of time delay,
bending of light, and moving source frequency shift are presented in terms of
the gravitational lens potential. Time delay results are applied in the
description of the procedure of the detection of gravitational waves.Comment: 21 pages, LaTex, to appear in C. L\"ammerzahl, C.W.F. Everitt, F.W.
  Hehl (eds.): ``Gyros, Clocks, and Interferometers: Testing Relativistic
  Gravity in Space'', Springer-Verlag, Berlin 200