ppxscal/embedding_network huggingface dataset:
Managing IFC for civil engineering projects
Authors: Renaud Vanlande, Christophe Cruz, Christophe Nicolle
Venue: Proceedings of the twelfth international conference on Information and knowledge management (2003)

The "Industrial Foundation Classes" (IFC) are an ISO norm to define all components of a building in a civil engineering project. IFC files are textual files whose size can reach 100 megabytes. Several IFC files can coexist on the same civil engineering project. Due to their size, their handling and sharing is a complex task. In this paper, we present an approach to automatically identify business objects in the IFC files and simplify their visualization and manipulation on the Internet. We construct an IFC Viewer which transforms the IFC file into a XML IFC tree manipulated through the 3D visualization of the building. The IFC Viewer composed a web-based platform called ACTIVe3D BUILD SERVER. This platform lets geographically dispersed project participants-from architects to electricians-directly use and exchange project documents in a centralized virtual environment during the life cycle of a civil engineering project.
A new linearly implicit trapezoidal formula for nonlinear parabolic equations
Authors: M. M. Chawla
Venue: Neural, Parallel Scientific Computations (2003)

Richtmyer's linearization (Richtmyer & Morton, 1967) applied to the classical trapezoidal formula (TF) leads to a linearly implicit trapezoidal formula, the so-called Lintrap formula. Lintrap has found extensive applications in computational fluid dynamics, plasma physics, nonlinear parabolic equations and blow-up solutions for ODEs. But, Lintrap is only first order for non-autonomous problems, and its local truncation error does not match that of TF. We present a new linearly implicit trapezoidal formula (LITF). The presented LITF is second order for non-autonomous problems and its principal local truncation error matches that of TF. For nonlinear parabolic problems, in comparison with the implicit Crank-Nicolson method, the present LITF obviates the need to solve a nonlinear system at each time step of integration. Numerical experiments reported illustrate these properties of LITF over that of Lintrap. Our experiments include viscous Burgers' equation, nonlinear diffusion and nonlinear reaction-diffusion. In each case, an LITF scheme is much superior than the Lintrap scheme and it provides accuracy comparable with that of the implicit Crank-Nicolson scheme without the need to solve a nonlinear system at each time step of integration.
Recursions for the Computation of Multipole Translation and Rotation Coefficients for the 3-D Helmholtz Equation
Authors: Nail A. Gumerov, Ramani Duraiswami
Venue: SIAM Journal on Scientific Computing (2003)

We develop exact expressions for the coefficients of series representations of translations and rotations of local and multipole fundamental solutions of the Helmholtz equation in spherical coordinates. These expressions are based on the derivation of recurrence relations, some of which, to our knowledge, are presented here for the first time. The symmetry and other properties of the coefficients are also examined and, based on these, efficient procedures for calculating them are presented. Our expressions are direct and do not use the Clebsch--Gordan coefficients or the Wigner 3-j symbols, although we compare our results with methods that use these to prove their accuracy. For evaluating an Nt term truncation of the translated series (involving $O(N_t^2)$ multipoles), our expressions require $O(N_t^3)$ evaluations, compared to previous exact expressions that require $O(N_t^5)$ operations.
Branch and peg algorithms for the simple plant location problem
Authors: Boris Goldengorin, Diptesh Ghosh, Gerard Sierksma
Venue: Computers and Operations Research (2004)

The simple plant location problem is a well-studied problem in combinatorial optimization. It is one of deciding where to locate a set of plants so that a set of clients can be supplied by them at the minimum cost. This problem often appears as a subproblem in other combinatorial problems. Several branch and bound techniques have been developed to solve these problems. In this paper we present two techniques that enhance the performance of branch and bound algorithms. The new algorithms thus obtained are called branch and peg algorithms, where pegging refers to fixing values of variables at each subproblem in the branch and bound tree, and is distinct from variable fixing during the branching process. We present exhaustive computational experiments which show that the new algorithms generate less than 60% of the number of subproblems generated by branch and bound algorithms, and in certain cases require less than 10% of the execution times required by branch and bound algorithms.
An approximation algorithm for scheduling two parallel machines with capacity constraints
Authors: Heng Yang, Yinyu Ye, Jiawei Zhang
Venue: Discrete Applied Mathematics (2003)

We consider the problem of scheduling n independent jobs on two identical parallel machines, with a limit on the number of jobs that can be assigned to each single machine, so as to minimize the total weighted completion time of the jobs. We study a semidefinite programming-based approximation algorithm for solving this problem and prove that the algorithm has a worst case ratio at most 1.1626.
Community Based Innovation -- A Method to Utilize the Innovative Potential of Online Communities
Authors: Johann Füller, Michael Bartl, Holger Ernst, Hans Mühlbacher
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 7 - Volume 7 (2004)

In this article the authors suggest a method to utilize the existing innovative potential of onlinecommunities by integrating its members virtually into New Product Development. The introduced concept of Community Based Innovation (CBI) which is founded on groundwork of social exchange and interaction theory was explored, tested and refined in several already conducted business projects in the consumer goods sector. As result of this action research the authors illustrate CBI as a practitioner's guideline consisting of four systemized steps along one case study in the automotive industry. The presented study helps to get a deeper understanding and a more detailed overview concerning the procedures and activities used in practice.
Circuit emulation services over ethernet-part 1: clock synchronization using timestamps
Authors: James Aweya
Venue: International Journal of Network Management (2004)

Due to Ethernet's ubiquity, simplicity, scalability and cost effectiveness there is significant customer demand for Ethernet-based access and transport in the metropolitan network. Many service providers have recognized this need and are currently establishing Ethernet-based services to meet this demand. The migration to all-Ethernet access will not be instantaneous since many customers currently have legacy TDM access interfaces on their routers and PBX equipment. Circuit Emulation Services (CES) over Ethernet provides TDM circuit emulation to support TDM traffic such as T1/E1, T3/E3, OC3/12, etc. This two-part paper presents the application of CES over Ethernet as well as a new technology that addresses the issues associated with clock recovery and synchronization in an Ethernet network with its inherent network jitter. Part 1 describes a clock synchronization technique where a transmitter periodically sends explicit time indications or timestamps to a receiver to enable the receiver to synchronize its local clock to the transmitter's clock.
Network Caching Strategies for a Shared Data Distribution for a Predefined Service Demand Sequence
Authors: Bharadwaj Veeravalli
Venue: IEEE Transactions on Knowledge and Data Engineering (2003)

In this paper, we address the problem of minimizing the cost of transferring a document or a file requested by a set of users geographically separated on a network of nodes. We concentrate on theoretical aspects of data migration and caching on high-speed networks. Following the information caching paradigm introduced in the literature [CHECK END OF SENTENCE], [CHECK END OF SENTENCE], we present polynomial time optimal caching strategies that minimize the total monetary cost of all the service requests by the users on a high-speed network. We consider a scenario in which a large pool of customers from one or more remote sites on a network demand a document, situated at some site, for their use. We also assume that the users can request the document at different time instants. This process of distributing the requested document incurs communication costs due to the use of communication resources and caching costs of the document at some server sites before it is delivered to the users at their desired time instances. We configure the network as a fully connected topology in which the service providers manage and control the distribution of the requested document among the users. For a high-speed network, we show that a single copy of the requested document is sufficient to serve all the user requests in an optimal manner. We extend the study to a homogeneous case in which the communication costs are identical and caching costs at all the sites are identical. In this case, we demonstrate the adaptability of the algorithm in generating more than one copy when needed by the minimization process. Using these strategies, the network service providers can decide when, where, and for how long the requested documents must be cached at vantage sites to obtain an optimal solution. Illustrative examples are provided to ease the understanding.
Making program execution comprehensible one level above the machine language
Authors: Cecile Yehezkel
Venue: Proceedings of the 8th annual conference on Innovation and technology in computer science education (2003)

The aim of courses in computer organization at the introductory level is not to produce qualified assembly language programmers but rather, to make the program's execution and the interaction with the hardware comprehensible at the lower programming language level (above machine code). We briefly describe an environment developed with this aim. Recent findings on the evaluation of visualization environment suggest that the evaluation should focus on the way students actually use these environments to better reveal the expected outcomes. To clarify this issue, we used an evaluation procedure based on this approach that provides far-reaching conclusions on the impact of the use of the environment on students' understanding of program execution.
Prediction of dose-time profiles for solar particle events using neural networks
Authors: Jennifer Lynn Hoff
Venue:  (2003)

When planning long duration space missions, radiation effects due to large solar particle events (SPEs) can become a major concern. As time in space increases, the chance that a measurable amount of dose is received from a SPE also increases. Therefore, a prediction mechanism for SPEs needs to be in place, which allows spacecraft operators to estimate the time until certain doses are reached following the onset of one of these events. Typical dose-time profiles of these events exhibit a Weibull functional form, which can be described by three fitting parameters. Since the profiles are nonlinear, the use of neural networks to approximate the profiles is ideal. The purpose of this research is to use neural networks to forecast the dose-time profiles of SPEs. A network set comprised of three networks is used to forecast each of the three Weibull parameters based on doses during the early stages of the SPE. The networks either utilize sliding or conventional time delay techniques. Once all three parameters have been forecasted, profiles are determined and compared to actual profiles. Sometimes a second, or even third event occurs before the first event is complete; therefore, the network set also has the ability to determine when one of these &ldquo;multiple-rise&rdquo; events occurs and can determine the profile for each subsequent event. From these profiles, radiation doses from a particular event and the length of time until applicable dose limits are reached can be forecasted. This research showed that neural networks do have the ability to forecast the Weibull parameters necessary for describing dose-time profiles of SPEs, both single and multiple-rise. Typically the forecasts were within thirty percent error of the actual profile before half of the event dose was received. Sometimes one or more of the parameters was not adequately forecasted, which caused the event to be either over- or under-predicted. However, when comparing times and doses exceeding particular dose limits, forecasts and actual values were always within a few percent of each other.
Constructing Lie algebras of first order differential operators
Authors: Jan Draisma
Venue: Journal of Symbolic Computation (2003)

We extend Guillemin and Sternberg's Realization Theorem for transitive Lie algebras of formal vector fields to certain Lie algebras of formal first order differential operators, and show that Blattner's proof of the Realization Theorem allows for a computer implementation that automatically reproduces many realizations derived in the existing literature, and that can also be used to compute new realizations. Applications include the explicit construction of quasi-exactly solvable Hamiltonians, and of finite-dimensional irreducible modules over semisimple Lie algebras.
Welcome
Authors: Newton Lee
Venue: Computers in Entertainment (CIE) (2003)

Welcome to the inaugural issue of the ACM Computers in Entertainment magazine! With the increasing media's attention on the influence of movies and video games on children, we examine the positive effects of entertainment on kids. In particular, we explore the educational value of entertainment and the technology behind it. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Composing instrument control dynamics
Authors: Dylan Menzies
Venue: Organised Sound (2002)

The expression gestural mapping is well imbedded in the language of instrument designers, describing the function from interface control parameters to synthesis control parameters. This function is in most cases implicitly assumed to be instantaneous, so that at any time its output depends only on its input at that time. Here more general functions are considered, in which the output depends on the history of input, especially functions that behave like physical dynamic systems, such as a damped resonator. Acoustic instruments are rich in dynamical behaviour. Introducing dynamics at the control stage of an electronic instrument can help compensate for lack of dynamics in later non-physical synthesis stages. A broadening of the function space offers new aesthetic possibilities for composing instruments. Examples are presented to illustrate the new design/composition mode as well as practical techniques. In this context, it is suggested that the word mapping be updated with the more descriptive expression dynamic control processing.
The Fused Bayesian Maximum Entropy-Variational Analysis Method for Computer Reconstruction of Remote Sensing Imagery
Authors: R. F. Vázquex-Bautista, Y. V. Shkvarko, L. J. Morales-Mendoza, L. Rizo-Domínguez
Venue: Proceedings of the 14th International Conference on Electronics, Communications and Computers (2004)

In this paper, we address the aggregated Bayesianmaximum entropy-variational analysis (BMEVA)-basedalgorithm for high resolution radar imageenhancement and denoising.The use of the variationalanalysis (VA) approach is formalized by imposing themetrics structures in the corresponding signal spaces.New formalism for combining the Bayesian maximumentropy (BME) strategy with the VA pardigm isdeveloped.The advantages in the image enhancementand denoising achieved using the proposed BMEVAmethod is illustrated through the numericalsimulators.
Designing for flexibility: separating user interface design from program logic and data
Authors: Marko Niinimäki, Miika Tuisku, Matti Heikkurinen
Venue: Proceedings of the 1st international symposium on Information and communication technologies (2003)

In modern software development it is increasingly important to bear in mind that the software should match with changing user requirements. The "design for change" perspective may not have been completely understood in the design for World Wide Web based applications. In this paper, we present methods to modularize storage access, domain objects, program logic and user interface into manageable modules. In our opinion, this will lead to better understanding of the software, help the users and programmers to communicate and help the programmers to manage their tasks. We shall, too, propose methods to express some of these modules in a declarative (XML) language, instead of a programming language.As a case study, we consider MDV, a document management program and demonstrate the practical benefits gained by using the modularization.
On finding a cyclic tour and a vehicle loading plan yielding maximum profit
Authors: E. Kh. Gimadi, N. I. Glebov, A. I. Serdyukov
Venue: Discrete Applied Mathematics (2004)

We consider a problem in which it is required to find a cyclic tour and a vehicle loading plan maximizing the total profit realized from purchasing and selling commodities loaded at vertices of the tour. It is shown that the problem reduces to the metric traveling salesman problem. We present polynomial-time approximation algorithms with proven performance guarantees for solving some variants of the problem corresponding to different loading schemes. We also identify special cases where our algorithms find either optimal or asymptotically optimal solutions.
Case study: visualization of 3D ultrasonic data
Authors: Georgios Sakas, Lars-Arne Schreyer, Marcus Grimm
Venue: Proceedings of the conference on Visualization '94 (1994)

3D Ultrasound is one of the most interesting non-invasive, non-radiative tomographic techniques. Rendering 3D modells from such data is not straight-forward due to the noisy, fuzzy nature of ultrasound imaging containing a lot of artefacts. In this paper we first apply speckle, median and gaussian prefiltering to improve the image quality. Using several semi-automatic segmentation tools we isolate interesting features within a few minutes. Our improved surface-extraction procedure enables volume rendering of high quality within a few seconds on a normal work-station, thus making the complete system suitable for routine clinical applications.
An Effective Image Steganographic Scheme Based on Wavelet Transformation and Pattern-Based Modification
Authors: Chin-Chen Chang, Tung-Shou Chen, Hsien-Chu Hsia
Venue: Proceedings of the 2003 International Conference on Computer Networks and Mobile Computing (2003)

In this paper, a new scheme for image steganography will be presented. The proposed scheme has the ability to hide secret message in a digital image. We call the scheme the pattern-based image steganography (PBIS). First, PBIS does discrete wavelet transformation (DWT) on the digital image; separates the transformation result into nonoverlapping blocks, and classifies the wavelet coefficients of these blocks into several patterns. The secret message is embedded into the image by changing the coefficients' patterns. The performance and reliability of PBIS are shown in the experimental results. The quality of the stego image of the proposed scheme is very close to that of the original one. Moreover, our scheme can be survived under JPEG lossy compression.
Solving motion planning problems by iterative relaxation of constraints
Authors: Osman Burchan Bayazit
Venue:  (2003)

This dissertation presents a new approach to improve automated motion planners. Automatic motion planning has application in many areas such as robotics, virtual reality systems, and computer-aided design. Surprisingly, a single class of planners, called probabilistic roadmap methods (PRMs), have proven effective on problems from all these domains. Strengths of PRMs are simplicity and efficiency, even in high-dimensional configuration spaces. Nevertheless, PRMs are not as effective in environments where the solution path requires the robot to pass through a narrow passage. In this dissertation, we suggest a hierarchical strategy addressing this problem where we first simplify the problem by relaxing some feasibility constraints, solve the easier version of the problem, and then use that solution to help find a solution for the harder problem. We show how this strategy can be applied to (i) &ldquo;virtual prototype&rdquo; analysis, where the goal is to find a removal path for one part (the robot) from an assembly of other parts (obstacles), (ii) &ldquo;ligand binding,&rdquo; where we generate candidate binding sites for a ligand in a large protein molecule, and (iii) &ldquo;deformable objects,&rdquo; where the robot can deform itself to avoid collision while following a path.
On cyclic &#x2329;m,n&#x232A;-enumerations
Authors: A. L. Perezhogin
Venue: Discrete Applied Mathematics (2004)

A word is called cyclic if each letter occurs in it an even number of times. A cyclic word X on the n-letter alphabet is called a cyclic 〈m,n〉-word if there is a letter in each subword of X occurring in it an odd number of times, and in each subword of X of length m all the letters are distinct. Such words induce 〈m,n,〉-enumerations of binary strings (Methods of Discrete Analysis for Solving Combinatorial, Problems, Vol. 34, Novosibirsk, Russia, 1980, pp. 8). For any positive integers n and m, where m < n, we build a cyclic 〈m,n〉-word of length l = m2n-⌈m/2⌉ and give an algorithm of finding the corresponding binary string from its number in the 〈m, n〉-enumeration obtained.
Circuit switching in the internet
Authors: Nick Mckeown
Venue:  (2003)

The motivation for this thesis is our desire to build faster routers and switches to accommodate for Internet traffic growth. For the past few years, Internet traffic has been doubling every year, and nothing indicates that it will decelerate in the near future. The Internet forwards information through packet switching, which has so far proven to scale from the early slow phone modems to the current fast link rates. However, it is unclear whether it will continue scaling to match future optical link rates. One could increase network capacity by building all-optical routers. However, these switches are not possible today because packet switching requires the buffering and processing of packets, and we do not (yet) know how to perform them in optics. On the other hand, optical circuit switches do not have these constraints, and thus they are already in use. The simplicity of the forwarding path in a circuit switch makes it faster than an equivalent router, even in electronics. In this thesis, I argue that we would greatly benefit from the use of circuit switching in the core of the network, in either electronic or optical form. Since the beginning of the Internet circuit switching has been widely used in the core of the network, but it is worth asking whether that is the best network architecture. Chapters 2 and 3 of this thesis analyze what type of network we would build were we to start with a clean slate. After analysis, modeling and simulation, I conclude that we would be better off with a hybrid network similar to the current one. A problem with the current circuits in the core is that they are completely decoupled of packets in the edges. Rather than following traffic patterns in real time, circuits are usually provisioned manually, and they change very slowly. Chapters 4 and 5 propose two evolutionary ways of integrating circuit and packet switching, so that circuits are automatically controlled by the traffic carried by IP. The first approach uses lightweight, fine circuits to carry single user flows, whereas the second multiplexes several flows onto heavyweight, coarse circuits.