ppxscal/embedding_network huggingface dataset:
Behavioral synthesis of combinational logic using spectral-based heuristics
Authors: M. A. Thornton, V. S. S. Nair
Venue: ACM Transactions on Design Automation of Electronic Systems (TODAES) (1999)

A prototype system developed to convert a behavioral representation of a Boolean function in OBDD form into an initial structural representation is described and experimental results are given. The system produces a multilevel circuit using heuristic rules based on properties of a subset of spectral coefficients. Since the behavioral description is in OBDD form, efficient methods are used to quickly compute the small subset of spectral coefficients needed for the application of the heuristics. The heuristics guide subsequent decompositions of the OBDD, resulting in an iterative construction of the structural form. At each stage of the translation, the form of the decomposition is chosen in order to achieve optimization goals.
Performance Analysis for Dual Band PCS Networks
Authors: Yi-Bing Lin, Wei-Ru Lai, Rong-Jaye Chen
Venue: IEEE Transactions on Computers (2000)

In a dual band personal communications services (PCS) network, heavy traffic areas are covered by microcells which overlay macrocells. In such a network, microcells and macrocells utilize different frequency bands. We propose an analytic model to study the performance of a dual band PCS architecture. Our model assumes that a PCS subscriber has a general residence time distribution in a microcell and the macrocell residence time distribution is derived from the microcell residence time distribution. An iterative algorithm is used to compute the overflow traffic from a microcell to its overlaid macrocell. Then, the call incompletion probability is computed by a macrocell model based on the overflow traffic. Our study indicates that the variance of the microcell residence time distribution and the number of microcells covered by a macrocell have significant effects on the call incompletion probability.
Coproducts and the cd-Index
Authors: Richard Ehrenborg, Margaret Readdy
Venue: Journal of Algebraic Combinatorics: An International Journal (1998)

The linear span of isomorphism classes of posets, {\cal P} , has a Newtonian coalgebra structure. We observe that the ab-index is a Newtonian coalgebra map from the vector space {\cal P} to the algebra of polynomials in the noncommutative variables a and b. This enables us to obtain explicit formulas showing how the cd-index of the face lattice of a convex polytope changes when taking the pyramid and the prism of the polytope and the corresponding operations on posets. As a corollary, we have new recursion formulas for the cd-index of the Boolean algebra and the cubical lattice. Moreover, these operations also have interpretations for certain classes of permutations, including simsun and signed simsun permutations. We prove an identity for the shelling components of the simplex. Lastly, we show how to compute the ab-index of the Cartesian product of two posets given the ab-indexes of each poset.
The traveling shutter wave analyses non-linear compliance during mechanical ventilation
Authors: Georg Mols, Volker Kessler, Albert Benzing, Matthias Schneider, Lioba Kühne, Klaus Geiger, Josef Guttmann
Venue: Technology and Health Care (1999)

Mechanical ventilation is an important, often life-saving component of modern intensive care medicine. However, it may further aggravate pulmonary pathology by endinspiratory overdistension of the alveoli or by their endexpiratory collapse. To prevent both the ventilator may be adjusted based on the slope of the pressure-volume curve, named as compliance, which is often determined by a stepwise inflation of the lungs. This maneuver gained no widespread clinical acceptance because of being cumbersome and invasive. Therefore, we developed a modification of the well known interrupter technique - the Traveling Shutter Wave. A wave of short-term (300 ms) occlusions travels over the tidal volume range. Differential compliance is calculated by division of volume and pressure differences between two adjacent occlusion maneuvers. The technique is well suited for the clinical setting because the ventilatory pattern does not need to be changed. This manuscript describes the realization of the Traveling Shutter Wave as well as its application in two patients.
Moving Mesh Strategy Based on a Gradient Flow Equation for Two-Dimensional Problems
Authors: Weizhang Huang, Robert D. Russell
Venue: SIAM Journal on Scientific Computing (1999)

In this paper we introduce a moving mesh method for solving PDEs in two dimensions. It can be viewed as a higher-dimensional generalization of the moving mesh PDE (MMPDE) strategy developed in our previous work for one-dimensional problems [W. Huang, Y. Ren, and R. D. Russell, SIAM J. Numer. Anal., 31 (1994), pp. 709--730]. The MMPDE is derived from a gradient flow equation which arises using a mesh adaptation functional in turn motivated from the theory of harmonic maps. Geometrical interpretations are given for the gradient equation and functional, and basic properties of this MMPDE are discussed. Numerical examples are presented where the method is used both for mesh generation and for solving time-dependent PDEs. The results demonstrate the potential of the mesh movement strategy to concentrate the mesh points so as to adapt to special problem features and to also preserve a suitable level of mesh orthogonality.
Forging a discipline: An outline history of software engineering education
Authors: James E. Tomayko
Venue: Annals of Software Engineering (1999)

Software engineering education has a 30&dash;year history. It is a story of academics struggling to fulfill industry needs with almost no support from computer science curriculum designers. It is a story of industry finally winning over some of academia to teach software engineering rather than vanilla computer science. It is a story of a discipline still incomplete, but having made great strides in the last decade. This paper discusses the succeeding eras of software engineering education, from lone teachers to master&rsquo;s curricula to undergraduate degree programs. Even though the maturity of the discipline is as yet unattained, it will achieve adult status through practice, not by waiting for academia to glacially catch up.
An empirical study of regression test application frequency
Authors: Jung-Min Kim, Adam Porter, Gregg Rothermel
Venue: Proceedings of the 22nd international conference on Software engineering (2000)

Regression testing is an expensive maintenance process used to revalidate modified software. Regression test selection (RTS) techniques try to lower the cost of regression testing by selecting and running a subset of the existing test cases. Many such techniques have been proposed and initial studies show that they can produce savings. We believe, however, that issues such as the frequency with which testing is done have a strong effect on the behavior of these techniques. Therefore, we conducted an experiment to assess the effects of test application frequency on the costs and benefits of regression test selection techniques. Our results expose essential tradeoffs that should be considered when using these techniques over a series of software releases.
A Bernoulli Cell-Based Investigation of the Non-Linear Dynamics in Log-Domain Structures
Authors: E. M. Drakakis, A. J. Payne
Venue: Analog Integrated Circuits and Signal Processing (2000)

This paper presents a low-level treatment of the non-linear dynamics encountered in log-domain structures, by means of a non-linear circuit element termed a Bernoulli Cell. This cell comprises an npn BJT and an emitter-connected grounded capacitor, and its dynamic behavior is determined by a differential equation of the Bernoulli form. The identification of the Bernoulli Cell leads to the creation of a system of linear differential equations which describe the dynamics of the derived log-domain state-variables. Furthermore, it is shown that the Bernoulli Cell has a memristive type dynamic behavior. The approach aids the analysis of log-domain circuits, and allows the internal non-linear currents to be conveniently expressed in closed analytical form. A worked example for a specific topology with confirming simulation results in both frequency and time-domain is presented. The celebrated Hodgkin-Huxley nerve axon membrane dynamics are also successfully simulated as a characteristic example of memristive behavior.
Modeling design constraints and biasing in simulation using BDDs
Authors: Jun Yuan, Kurt Shultz, Carl Pixley, Hillel Miller, Adnan Aziz
Venue: Proceedings of the 1999 IEEE/ACM international conference on Computer-aided design (1999)

Constraining and input biasing are frequently used techniques in functional verification methodologies based on randomized simulation generation. Constraints confine the simulation to a legal input space, while input biasing, which can be considered as a probabilistic constraint, makes it easier to cover interesting &ldquo;corner&rdquo; cases. In this paper, we propose to use constraints and biasing to form a simulation environment instead of using an explicit testbench in hierarchical functional verification. Both constraints and input biasing can depend on the state of the design and thus are very expressive in modeling the environment. We present a novel method that unifies the handling of constraints and biasing via the use of Binary Decision Diagrams (BDDs). The distribution of input vectors under the effect of constraints and input biasing are determined by what we refer to as the constrained probabilities. A BDD representing the constraints is first built, then an algorithm is applied to bias the branching probabilities in the BDD. During simulation, this annotated BDD is used to generate input vectors whose distribution match their predetermined constrained probabilities. The simulation generation is a one-pass process, i.e., no backtracking or retry is needed. Also, we describe a partitioning method to minimize the size of BDDs used in simulation generation. Our techniques were used in the verification of a set of commercial designs; experimental results demonstrated their effectiveness.
Performance Evaluation and Analysis of Monocular Building Extraction From Aerial Imagery
Authors: Jefferey A. Shufelt
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1999)

Research in monocular building extraction from aerial imagery has neglected performance evaluation in three areas: unbiased metrics for quantifying detection and delineation performance, an evaluation methodology for applying these metrics to a representative body of test imagery, and an approach for understanding the impact of image and scene content on building extraction algorithms. This paper addresses these areas with an end-to-end performance evaluation of four existing monocular building extraction systems, using image space and object space-based metrics on 83 test images of 18 sites. This analysis is supplemented by an examination of the effects of image obliquity and object complexity on system performance, as well as a case study on the effects of edge fragmentation. This widely applicable performance evaluation approach highlights the consequences of various traditional assumptions about camera geometry, image content, and scene structure, and demonstrates the utility of rigorous photogrammetric object space modeling and primitive-based representations for building extraction.
Dimension of Projections in Boolean Functions
Authors: Ramamohan Paturi, Francis Zane
Venue: SIAM Journal on Discrete Mathematics (1998)

A projection is a subset of {0,1}n given by equations of the form xi = xj, xi = \bar{x}j, xi = 0, and xi = 1, where for $1\leq i \leq n$, xi are Boolean variables and $\bar{x}i are their complements. We study monochromatic projections in 2-colorings of an n-dimensional Boolean cube. We also study the dimension of the largest projection contained in a set specified by its density. We prove almost matching lower and upper bounds on the density of a set required to guarantee the existence of a d-dimensional projection. We also prove almost tight upper and lower bounds on the dimension of monochromatic projections in arbitrary Boolean functions. We then prove almost tight upper and lower bounds on the dimension of monochromatic projections in Boolean functions represented by low degree GF(2) polynomials. It follows from these lower bounds that low-degree GF(2) polynomials can define Boolean functions which are close to being extremal with respect to the property of having no large dimensional monochromatic projections.
Use and perceived value of computer-based information systems in supporting the decision making of German managers
Authors: George E. Vlahos, Thomas W. Ferratt, Georg Knoepfle
Venue: Proceedings of the 2000 ACM SIGCPR conference on Computer personnel research (2000)

This study surveyed a sample of German managers to investigate the amount of information technology (IT) these managers used and their perceived value and satisfaction with their existing computer-based information systems (CBIS) in providing helpful information for making successful and effective decisions. A detailed analysis of the responses produced the following findings: (1) The German sample of managers was predominantly male, older, had several college computer courses, and was comprised mainly of middle and top level managers. (2) The German managers used IT rather heavily, approximately 10 hours per week. This result was similar to those reported in several previous studies. (3) First-line managers were the heaviest users of IT and perceived the greatest value of CBIS for decision making. Top level managers were the lightest users of IT but perceived greater value of CBIS than middle managers. From the functional areas, managers in information systems and accounting/finance were the heaviest users of IT and perceived the greatest value of CBIS. For the overall sample, there was a significant correlation between amount of use of IT and perceived value of CBIS. (4) The majority of the respondents were confident that the information they were getting from their CBIS was not compromised due to lack of adequate security. (5) About half of the responding managers reported that they helped specify more than sixty percent (60%) of the content or format of the information presented to them by CBIS. (6) Eighty four percent (84%) of the respondents rated their corporation's amount of investment in IT to support managerial needs as adequate or better.
A Quantile Regression Approach to Generating Prediction Intervals
Authors: James W. Taylor, Derek W. Bunn
Venue: Management Science (1999)

Exponential smoothing methods do not involve a formal procedure for identifying the underlying data generating process. The issue is then whether prediction intervals should be estimated by a theoretical approach, with the assumption that the method is optimal in some sense, or by an emp irical procedure. In this paper we present an alternative hybrid approach which applies quantile regression to the empirical fit errors to produce forecast error quantile models. These models are functions of the lead time, as suggested by the theoretical variance expressions. In addition to avoiding the optimality assumption, the method is nonparametric, so there is no need for the common normality assumption. Application of the new approach to simple, Holt's, and damped Holt's exponential smoothing, using simulated and real data sets, gave encouraging results.
Composite model-checking: verification with type-specific symbolic representations
Authors: Tevfik Bultan, Richard Gerber, Christopher League
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (2000)

There has been a surge of progress in automated verification methods based on state exploration. In areas like hardware design, these technologies are rapidly augmenting key phases of testing and validation. To date, one of the most successful of these methods has been symbolic model-checking, in which large finite-state machines are encoded into compact data structures such as Binary Decision Diagrams (BDDs), and are then checked for safety and liveness properties. However, these techniques have not realized the same success on software systems. One limitation is their inability to deal with infinite-state programs, even those with a single unbounded integer. A second problem is that of finding efficient representations for various variable types. We recently proposed a model-checker for integer-based systems that uses arithmetic constraints as the underlying state representation. While this approach easily verified some subtle, infinite-state concurrency problems, it proved inefficient in its treatment of boolean and (unordered) enumerated types&mdash;which are not efficiently representable using arithmetic constraints. In this article we present a new technique that combines the strengths of both BDD and arithmetic constraint representations. Our composite model merges multiple type-specific symbolic representations in a single model-checker. A system's transitions and fixpoint computations are encoded using both BDD (for boolean and enumerated types) and arithmetic constraints (for integers) representations, where the choice depends on the variable types. Our composite model-checking strategy can be extended to other symbolic representations provided that they support operations such as intersection, union, complement, equivalence checking, and relational image computation. We also present conservative approximation techniques for composite representations to address the undecidability of model-checking on infinite-state systems. We demonstrate the effectiveness of our approach by analyzing two example software specifications which include a mixture of booleans, integers, and enumerated types. One of them is a requirements specification for the control software of a nuclear reactor's cooling system, and the other one is a protocol specification.
Single display groupware: a model for co-present collaboration
Authors: Jason Stewart, Benjamin B. Bederson, Allison Druin
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

We introduce a model for supporting collaborative work between people that are physically close to each other. We call this model Single Display Groupware (SDG). In this paper, we describe the model, comparing it to more traditional remote collaboration, We describe the requirements that SDG places on computer technology, and our understanding of the benefits and costs of SDG systems. Finally, we describe a prototype SDG system that we built and the results of a usability test we ran with 60 elementary school children.
Solving two application problems
Authors: Kenneth S. Schneider
Venue: International Journal of Network Management (1997)

In this article application stories illustrate two rather uncommon network remodelings&mdash;one for a semiconductor fabrication plant, the other for a supermarket&mdash;in which recently developed hardware is applied to redesign and optimize the networks. &copy; 1997 John Wiley Sons, Ltd.
Coarse-Grid Correction for Nonelliptic and Singular Perturbation Problems
Authors: Irad Yavneh
Venue: SIAM Journal on Scientific Computing (1998)

The suitability of coarse-grid correction operators for multigrid solution of discretized nonelliptic partial differential equations is studied. It is found that the requirements for the orders of intergrid transfers and the order of approximation of the coarse-grid operators differ in an important way from the well-known "rules" pertaining to elliptic operators. Both Galerkin coarsening and coarsening schemes based on the differential operator are examined, and new coarse-grid correction strategies are suggested in light of this analysis.
A call admission and control scheme for quality-of-service (QoS) provisioning in next generation wireless networks
Authors: S. K. Das, R. Jayaram, N. K. Kakani, Sanjoy K. Sen
Venue: Wireless Networks (2000)

We propose a framework for quality&dash;of&dash;service &lpar;QoS&rpar; provisioning for multimedia services in next generation wireless access networks. This framework aims at providing a differentiated treatment to multimedia traffic flows at the link layer, which can be broadly classified as real&dash;time &lpar;or delay&dash;sensitive&rpar; and non&dash;real&dash;time &lpar;or delay&dash;tolerant&rpar;. Various novel schemes are proposed to support the differential treatment and guarantee QoS. These schemes include bandwidth compaction, channel reservation and degradation, with the help of which a call admission and control algorithm is developed. The performance of the proposed framework is captured through analytical modeling and simulation experiments. Analytically, the average carried traffic and the worst case buffer requirements for real&dash;time and non&dash;real&dash;time calls are estimated. Simulation results show up to 21% improvement in the admission probability of real&dash;time calls and up to 17% improvement in the admission probability of non&dash;real&dash;time calls, when various call control techniques like bandwidth compaction are employed. Using our channel reservation technique, we observe a 12% improvement in the call admission probability compared to another scheme proposed in the literature.
Cost-based query optimization for metadata repositories
Authors: Martin Staudt, René Soiron, Christoph Quix, Matthias Jarke
Venue: ACM SIGAPP Applied Computing Review (1999)

Query optimization strategies for repository systems must take into account the rich and often unpredictable structure of metadata, as well as supporting complex analysis of relationships between those structures. This paper describes rationale, design, and system integration of a cost-based query optimizer offered in ConceptBase, a metadata manager that supports these capabilities by a deductive object-oriented data model. In contrast to most implemented DBMS, the optimizer is not based on the concept of join selectivity, but on detailed distribution information about object and literal fan-out, with heavy exploitation of materialized views and end-biased histograms. Experiences from two real-world applications in software configuration management and cooperative design demonstrate the practical advantages but also point to some lessons for further improvement.
Numerical Calculation of Three-Dimensional Interfacial Potential Flows Using the Point Vortex Method
Authors: David J. Haroldsen, Daniel I. Meiron
Venue: SIAM Journal on Scientific Computing (1998)

An application of the point vortex method to the singular Biot--Savart integrals used in water wave calculations is presented. The error for this approximation is shown to be a series in odd powers of h. A method for calculating the coefficients in the series is presented.