ppxscal/embedding_network huggingface dataset:
Persona development for information-rich domains
Authors: Rashmi Sinha
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

Designing information architecture for complex websites requires understanding user information needs and mental models in that domain. Personas, or user archetypes, created for such domains should also reflect types of information needs, and usage of information set. We have created a statistical technique to identify important underlying groupings of information needs. In a preliminary study, we show how designers can use this information in conjunction with data from interviews and observations to generate and refine personas.
On the Existence of Solutions to the Dynamic User Equilibrium Problem
Authors: Daoli Zhu, Patrice Marcotte
Venue: Transportation Science (2000)

This paper is concerned with the existence of solutions to a dynamic network equilibrium problem modeled as an infinite dimensional variational inequality. Our results are based on properties of operators that map path flow departure rates to consistent time-dependent path flows and other link performance functions. The existence result requires the introduction of a novel concept that strengthens the familiar concept of First-In-First-Out (FIFO).
An arbitrary Lagrangian-Eulerian finite element method for interactions of airflow and a moving AGV in a cleanroom
Authors: Suh-Jenq Yang
Venue: Finite Elements in Analysis and Design (2003)

The motions of the airflow induced by the movement of an automatic guided vehicle (AGV) in a cleanroom are numerically studied. This subject is an important issue of microcontamination control for the semiconductor process. The characteristics of the airflow induced by the movement of the AGV are dynamic and are classified as a type of moving boundary problems. An arbitrary Lagrangian-Eulerian finite element method with moving meshes is adopted to analyze this problem. Two different moving velocities of the AGV and two different positions of the wafer cassette under Reynolds number Re = 500 are considered in details. The results show that the recirculation zones, which inhibit removing microcontaminants, are observed around the AGV and wafer cassette, and the formations of recirculation zones are remarkably dependent upon the moving velocity of the AGV and the position of the wafer cassette. These phenomena are remarkably different from those of a moving AGV regarded as a stationary one.
Superconvergence of solution derivatives for the Shortley-Weller difference approximation of Poisson's equation. Part I: smoothness problems
Authors: Zi-Cai Li, Tetsuro Yamamoto, Qing Fang
Venue: Journal of Computational and Applied Mathematics (2003)

The finite difference method (FDM) using the Shortley-Weller approximation can be viewed as a special kind of the finite element methods (FEMs) using the piecewise bilinear and linear functions, and involving some integration approximation. When u ∈ C3(S) (i.e., u ∈ C3,0(S)) and f ∈ C2(S), the superconvergence rate O(h2) of solution derivatives in discrete H1 norms by the FDM is derived for rectangular difference grids, where h is the maximal mesh length of difference grids used, and the difference grids are not confined to be quasiuniform. Comparisons are made on the analysis by the maximum principle and the FEM analysis, conversions between the FDM and the linear and bilinear FEMs are discussed, and numerical experiments are provided to support superconvergence analysis made.
On Natural Continua of Periodic Solutions of the Systems with Hysteresis
Authors: D. I. Rachinskii
Venue: Automation and Remote Control (2003)

Theorems on the existence of continua of periodic solutions for systems with hysteretic nonlinearities of the type of Preisah models are suggested. It is found that in the general situation, the standard criteria for existence of at least one periodic solution, which rest on the use of prior upper-bound estimates of the norm of periodic solutions and the Leray&ndash;Schauder method, ensure the existence of a one-parameter continuum of periodic solutions to these systems. The proofs are based on the use of new classes of operators that describe periodic responses of hysteretic nonlinearities to periodic inputs.
On theoretical and practical considerations of path selection for delay fault testing
Authors: Jing-Jia Liou, Li-C. Wang, Kwang-Ting Cheng
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

In current industrial practice, critical path selection is an indispensable step for AC delay test and timing validation. Traditionally, this step relies on the construction of a set of worse-case paths based upon discrete timing models. The assumption of discrete timing models can be invalidated by delay effects in the deep sub-micron domain, where timing defects and process variation are statistical in nature. In this paper, we study the problem of optimizing critical path selection, under both fixed delay and statistical delay assumptions. With a novel problem formulation and new theoretical results, we prove that the problem in both cases are computationally intractable. We then discuss practical heuristics and their theoretical performance bounds, and demonstrate that among all heuristics under consideration, only one is theoretically feasible. Finally, we provide consistent experimental results based upon defect-injected simulation using an efficient statistical timing analysis framework.
p-Bézier curves, spirals, and sectrix curves
Authors: J. Sánchez-Reyes
Venue: Computer Aided Geometric Design (2002)

We elucidate the connection between Bézier curves in polar coordinates, also called p-Bézier or focal Bézier curves, and certain families of spirals and sectrix curves, p-Bézier curves are the analogue in polar coordinates of nonparametric Bézier curves in Cartesian coordinates. Such curves form a subset of rational Bézier curves characterized by control points on radial directions regularly spaced with respect to the polar angle, and weights equal to the inverse of the polar radius. We show that this subset encompasses several classical sectrix curves, which solve geometrically the problem of dividing an angle into equal spans, and also spirals defining the trajectories of particles in central fields, First, we identify as p-Bézier curves a family of sinusoidal spirals that includes Tschirnhausen's cubic. Second, the trisectrix of Maclaurin and their generalizations, called arachnidas. Finally, a special class of epi spirals that encompasses the trisectrix of Delanges.
ECO algorithms for removing overlaps between power rails and signal wires
Authors: Hua Xiang, Kai-Yuan Chao, D. F. Wong
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Design ECO commonly happens in industry due to constraints or target changes from manufacturing, marketing, reliability, or performance. At each step, designers usually want to modify the existing solution incrementally and keep the design as close as possible to the existing one. In this paper, we address the PSO (Power rail - Signal wire Overlap) problem which solves overlaps between power rails and signal wires due to the changes in power rail design on the top layer of a multiple layer routing region. PSO problems are frequently caused by changes from power delivery system or package design. The new routing solution satisfies the following constraints: 1) Keep the routing of power rails in the new design unchanged. 2) Only the routing of the top two layers is changed. 3) Horizontal (vertical) signal wire segments on the top layer can only move up/down (left/right). At the same time, the new routing solution keeps the routing pattern unchanged. This requires: a) If one end point of a horizontal (vertical) wire segment on the top layer is a fixed pin, this segment can not move. b) If vertical (horizontal) projections of two horizontal (vertical) signal wire segments have overlaps, then the up/down (left/right) relationship should not be changed. c) If two horizontal (vertical) segments belonging to different nets are on the same track, their left/right (up/down) relationship should not be changed as long as the two segments still exist in the new solution. 4) For each signal wire segment, the deviation (i.e., the difference between its new position and the old one) should not exceed the user-defined allowable deviation bound. Different bounds can be set on different segments. We propose two algorithms to solve the PSO problem. Both algorithms guarantee to find a feasible solution as long as one exists. One is faster, while the other makes effort to minimize the total deviation as well as the max deviation. According to time and quality requirements, users can choose an appropriate algorithm to solve the problem. For a set of industrial test circuits, we were able to remove all overlaps between power rails and signal wires with minimal wire deviation.
Children of the information age: a reversal of roles
Authors: Edna Aphek
Venue: Ubiquity (2002)

Understanding the unique characteristics of the high-tech, digital generation.
Modeling Farmers' Response to Uncertain Rainfall in Burkina Faso: A Stochastic Programming Approach
Authors: Arno Maatman, Caspar Schweigman, Arjan Ruijs, Maarten H. van Der Vlerk
Venue: Operations Research (2002)

Farmers on the Central Plateau of Burkina Faso in West Africa cultivate under precarious conditions. Rainfall variability is extremely high in this area and accounts for much of the uncertainty surrounding the farmers' decision-making process. Strategies to cope with these risks are typically dynamic. Sequential decision making is one of the most important ways to cope with risk due to uncertain rainfall. In this paper, a stochastic programming model is presented to describe farmers' sequential decisions in reaction to rainfall. The model describes farmers' strategies of production, consumption, selling, purchasing, and storage from the start of the growing season until one year after the harvest period. This dynamic model better describes farmers' strategies than do static models that are usually applied. This study draws important policy conclusions regarding reorientation of research programs and illustrates how operations research techniques can be usefully applied to study grass root problems in developing countries.
Erratum to "Bias and Sysematic Change in the Parameter Estimates of Macro-Level Diffusion Models"
Authors: Christoph Van Den Bulte, Gary L. Lilien
Venue: Marketing Science (1998)

Due to a printer's error, the acknowledgment footnote (footnote 4, p. 350) was deleted from the final page proofs of "Bias and Systematic Change in the Parameter Estimates of Macro-Level Diffusion Models," by Christoph Van den Bulte and Gary L. Lilien, Vol. 16 No. 4 1997, pp. 338Â 353.
Stretching the Iron Cage: The Constitution and Implications of Routine Workplace Resistance
Authors: Pushkala Prasad, Anshuman Prasad
Venue: Organization Science (2000)

Organizational scholars have shown considerable interest in the rise of complex systems of organizational control, sometimes referred to metaphorically as the process of tightening the iron cage, as well as patterns of workplace resistance to it. More recently, the scholarly spotlight seems to have shifted from formal modes of employee resistance to more informal orroutine forms of workplace resistance. This paper presents a detailed ethnographic account of informal resistance and its ability to limit managerial control in a health maintenance organization undergoing the computerization of its administrative functions. Our study adopts a more problematic approach to understanding routine resistance, tracing itsdiscursive constitution in the workplace. Using the findings of an ethnographic study involving observation and interviews, we show how routine resistance was discursively constituted and how it limited organizational control in interesting and unexpected ways. This discursive constitution was achieved through (a) owning resistance, (b) naming resistance, and (c) designating indirect resistance. The paper also analyzes how these different discursive constructions limited managerial control by affirming autonomous self-identities, renegotiating roles and relationships, and reinterpreting dominant managerial discourses. Finally, broader implications for understanding routine resistance in organizations are drawn.
Satisfying customer bandwidth demand in IP data networks
Authors: Yaakov Kogan, Gangaji Maguluri, Gomathi Ramachandran
Venue: Performance Evaluation (2003)

We introduce the notion of customer access fulfillment in IP data networks and provide a quantitative characterization of the fulfillment using measurements of the router uplink (link connecting a router to the backbone) utilization. The threshold for the uplink utilization is calculated for a given probability of customer fulfillment based on the normal approximation. We use three different stochastic models to prove the normal approximation for the distribution of the uplink utilization. The convergence to the Gaussian diffusion process is proved in the framework of the nonstationary exponential Benes buffer model. In a special case of an alternating renewal process, we show that the fulfillment can be evaluated based on measurements of the mean uplink utilization. We also prove that the distribution of utilized uplink capacity is asymptotically normal in the context of large generalized Erlang and Engset models. We analyze 5 min measurements of router uplink utilization and show that their empirical distribution is close to normal.
Multicoloring trees
Authors: Magnús M. Halldórsson, Guy Kortsarz, Andrzej Proskurowski, Ravit Salman, Hadas Shachnai, Jan Arne Telle
Venue: Information and Computation (2003)

Scheduling jobs with pairwise conflicts is modeled by the graph multicoloring problem. It occurs in two versions: in the preemptive case, each vertex may get any set of colors, while in the non-preemptive case, the set of colors assigned to each vertex has to be contiguous. We study these versions of the multicoloring problem on trees, under the sum-of-completion-times objective. In particular, we give a quadratic algorithm for the non-preemptive case, and a faster algorithm in the case that all job lengths are short, while we present a polynomial-time approximation scheme for the preemptive case.
A new method of increasing the order of convergence step by step
Authors: Fangyu Sun, Xin Zhang
Venue: Applied Mathematics and Computation (2003)

In order to derive iterations for simultaneously finding all zeros of an algebraic polynomial with high order convergence, based on D-K method we construct some iterations of increasing the order of convergence step by step.
Automatic effective verification method for distributed and concurrent systems using timed language inclusion
Authors: Satoshi Yamane
Venue: Engineering of distributed control systems (2001)

In distributed and concurrent systems, the notions of fairness and time are important as follows: (1)Fairness is a mathematical abstraction in distributed and concurrent systems. Fairness abstracts the details of fair schedulers and the speeds of independent processors. (2)The distributed and concurrent systems have to meet certain hard real-time constraints, and the correctness of them depends on the actual values of the delays.In this paper, we propose the specification and verification method of fairness and time in distributed and concurrent systems as follows: (1)In order to specify fairness, an enable condition and a performed condition are attached to a finite set of states in our proposed specification method. (2)In order to effectively verify distributed and concurrent systems, we restrict timing constraints of timed automaton such that in cycles we must specify timing constraints about the clock variables after they are reset to zero.
STORM: lightning-fast resource management
Authors: Eitan Frachtenberg, Fabrizio Petrini, Juan Fernandez, Scott Pakin, Salvador Coll
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

Although workstation clusters are a common platform for high-performance computing (HPC), they remain more difficult to manage than sequential systems or even symmetric multiprocessors. Furthermore, as cluster sizes increase, the quality of the resource-management subsystem---essentially, all of the code that runs on a cluster other than the applications---increasingly impacts application efficiency. In this paper, we present STORM, a resource-management framework designed for scalability and performance. The key innovation behind STORM is a software architecture that enables resource management to exploit low-level network features. As a result of this HPC-application-like design, STORM is orders of magnitude faster than the best reported results in the literature on two sample resource-management functions: job launching and process scheduling.
Incremental unknowns and graph techniques in three space dimensions
Authors: Salvador Garcia
Venue: Applied Numerical Mathematics (2003)

For three space dimensions, from now on, we show that the condition number of the incremental unknowns matrix associated to the Laplace operator is O(1/H2)O((1/h)|log h|), where H is the mesh size of the coarsest grid and where h is the mesh size of the finest grid; furthermore, if block diagonal scaling is used, the condition number of the preconditioned incremental unknowns matrix associated to the Laplace operator turns out to be O(1/h), these conditioning results proved by using a generic algebraic conditioning analysis-based upon graph techniques--and by setting up a discrete inequality. In contrast, the condition number of the nodal unknowns matrix associated to the Laplace operator is O (1/h2). Therefore, the incremental unknowns preconditioner is an efficient preconditioner in three space dimensions.
Planning Home Assistance for Aids Patients in the City of Rome, Italy
Authors: Michael J. Brusco, Larry W. Jacobs, V. De Angelis
Venue: Interfaces (1998)

In allocating resources to health-care services, the main difficulties derive from uncertainty concerning the number of patients who need the service and the level of care required by each patient who is entitled to receive it. I deal with the problem of allocating resources to the home-care service provided to AIDS patients in the city of Rome, Italy, which include medical assistance provided by nurses and doctors and social assistance and accompaniment of patients provided by social workers. A simple linear programming model solves the problem for single organizations, which provide assistance within a given budget, and for public-health authorities, which have to evaluate the results of tentative budgets assigned to home care.
Business mobilize production through markets: parametric modeling of path-dependent outcomes in oriented network flows
Authors: Harrison C. White
Venue: Complexity (2002)

Business is modeled as interlocking social constructions that emerge in mobilizing differentiated production flows amidst uncertainty. The model is stochastic, nonlinear, and sited in a network ecology for identities that have come to share a discourse which itself recognizes embeddings in distinct levels of firm, market, and sector. Three counterintuitive findings are emphasized: competitive markets can be viable for increasing returns to scale; effects of substitutability/saturation are opposite for different sorts of competititive markets; and markets orient to flow uncertainty.
Architecture for a massively multiplayer online role playing game engine
Authors: Sergio Caltagirone, Matthew Keys, Bryan Schlief, Mary Jane Willshire
Venue: Journal of Computing Sciences in Colleges (2002)

Faster networks, faster processors and 3D accelerator cards have contributed to the push for a new genre of online games, the Massively Multiplayer Online Role Playing Game, MMORPG. This paper presents a high-level software architecture for building a MMORPG engine. Six goals for the architecture are set, the architecture is presented and then examined to determine how well the goals have been met. The architecture blends in a unique way several classical software architecture patterns, using the strength of each to achieve the goals for the system.
An abstract architecture for dependable and flexible distributed applications
Authors: Zhuang Hong, Jie Xu, Keith Bennett
Venue: Systems engineering for business process change: new directions (2002)

Distributed software systems are increasingly used to support business applications. This requires three crucial properties of any architecture: first, the system has well defined dependability attributes; second, it is flexible, in that it can be modified to accommodate new or changed applications; and third, the several subcomponents or subsystems can interwork to meet the needs of the large-scale distributed application. Existing work has concentrated on solving these problems as separate issues. A new system abstraction model is proposed here in which these problems are addressed together. Dependability is achieved largely by the use of coordinated atomic actions to structure and control the dynamic behaviour of the system, by providing effective error recovery and supporting dynamic system change. Flexibility and interworking are addressed by multiple architecture levels and component interaction mechanisms. Software components involved in the system are classified into three loosely coupled levels: "core", "internal-business-logic" and "service interfaces". While the interface to the system environment permits the highest level of flexibility, the core components remain relatively stable. An example implementation of the proposed abstract architecture is outlined by means of available technologies including XML, Java Server Pages, CORBA and JDBC.
Virtual-topology adaptation for WDM mesh networks under dynamic traffic
Authors: Aysegül Gençata, Biswanath Mukherjee
Venue: IEEE/ACM Transactions on Networking (TON) (2003)

We present a new approach to the virtual-topology reconfiguration problem for a wavelength-division-multiplexing-based optical wide-area mesh network under dynamic traffic demand. By utilizing the measured Internet backbone traffic characteristics, we propose an adaptation mechanism to follow the changes in traffic without a priori knowledge of the future traffic pattern. Our work differs from most previous studies on this subject which redesign the virtual topology according to an expected (or known) traffic pattern, and then modify the connectivity to reach the target topology. The key idea of our approach is to adapt the underlying optical connectivity by measuring the actual traffic load on lightpaths continuously (periodically based on a measurement period) and reacting promptly to the load imbalances caused by fluctuations on the traffic, by either adding or deleting one or more lightpath at a time. When a load imbalance is encountered, it is corrected either by tearing down a lightpath that is lightly loaded or by setting up a new lightpath when congestion occurs. We introduce high and low watermark parameters on lightpath loads to detect any over- or underutilized lightpath, and to trigger an adaptation step. We formulate an optimization problem which determines whether or not to add or delete lightpaths at the end of a measurement period, one lightpath at a time, as well as which lightpath to add or delete. This optimization problem turns out to be a mixed-integer linear program. Simulation experiments employing the adaptation algorithm on realistic network scenarios reveal interesting effects of the various system parameters (high and low watermarks, length of the measurement period, etc.). Specifically, we find that this method adapts very well to the changes in the offered traffic.