ppxscal/embedding_network huggingface dataset:
Discriminability of Real and Virtual Surfaces with Triangular Gratings
Authors: Matthew Kocsis, Hong Z. Tan, Bernard D. Adelstein
Venue: Proceedings of the Second Joint EuroHaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2007)

Human sensitivity to height differences in textured surfaces is on the order of microns. Research on human texture perception requires texture samples with precisely controlled micro-geometry. This can be achieved with an electrical discharge machining (EDM) procedure, but the process is time consuming and labor intensive. An alternative approach is to simulate textured surfaces with a haptic interface with high position resolution. The present study measured the amplitude discrimination thresholds for surfaces with triangular gratings using real EDM textured samples and virtual textures rendered with a highprecision force-feedback device called the ministick. The results indicated that the just noticeable differences for real and virtual textures, respectively 3.69±0.65 and 4.94±0.96 ìm, were of similar magnitude. Therefore, we propose that this device is suitable for the study human perception of surface micro-geometry with features on the scale of human perceptual resolution.
Tool Support for Inspecting the Code Quality of HPC Applications
Authors: Thomas Panas, Dan Quinlan, Richard Vuduc
Venue: ICSEW (2007)

The nature of HPC application development encourages ad hoc design and implementation, rather than formal requirements analysis and design specification as is typical in software engineering. However, we cannot simply expect HPC developers to adopt formal software engineering processes wholesale, even while there is a need to improve software structure and quality to ensure future maintainability. Therefore, we propose tools that HPC developers can use at their discretion to obtain feedback on the structure and quality of their codes. This feedback would come in the form of code quality metrics and analyses, presented when necessary in intuitive and interactive visualizations. This paper summarizes our implementation of just such a tool, which we apply to a standard HPC benchmark as "proofof- concept."
A proposed likelihood transformation for speaker verification
Authors: D. Tran
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

Most of current normalisation methods for speaker verification are based on the ratio of the claimed speaker's and impostors' likelihood functions. As an extension, we propose alternative normalisation methods, which are based on the ratio of functions of the claimed speaker's and impostors' likelihood functions. A likelihood transformation is proposed in this paper to relate current and proposed methods. We also report several significant experimental results performed on the T146, the ANDOSL and the YOHO corpora using these proposed normalisation methods.
Note: On the number of words containing the factor (aba)k
Authors: Ioan Tomescu
Venue: Discrete Applied Mathematics (2007)

In this paper a recurrence relation satisfied by the number L(n) of words of length n over an alphabet A of cardinality m(m>=2) not containing the factor (aba)^k(a"~k(n)/lnn~. Using the properties of the roots of the recurrence satisfied by L(n) it is shown that if limsup"n"->"~k(n)/lnn>1/(3lnm) then this property is false. Moreover, if lim"n"->"~(lnn-3klnm)=@h@?R then lim"n"->"~|W(n,(aba)^k^"^n,A)|/m^n=1-exp(-(1-1/m^3)exp(@h)), where W(n,(aba)^k^"^n,A) denotes the set of words of length n over A containing the factor (aba)^k^"^n.
Backfilling Using System-Generated Predictions Rather than User Runtime Estimates
Authors: Dan Tsafrir, Yoav Etsion, Dror G. Feitelson
Venue: IEEE Transactions on Parallel and Distributed Systems (2007)

The most commonly used scheduling algorithm for parallel supercomputers is FCFS with backfilling, as originally introduced in the EASY scheduler. Backfilling means that short jobs are allowed to run ahead of their time provided they do not delay previously queued jobs (or at least the first queued job). To make such determinations possible, users are required to provide estimates of how long jobs will run, and jobs that violate these estimates are killed. Empirical studies have repeatedly shown that user estimates are inaccurate, and that system-generated predictions based on history may be significantly better. However, predictions have not been incorporated into production schedulers, partially due to a misconception (that we resolve) claiming inaccuracy actually improves performance, but mainly because underprediction is technically unacceptable: Users will not tolerate jobs being killed just because system predictions were too short. We solve this problem by divorcing kill-time from the runtime prediction and correcting predictions adaptively as needed if they are proved wrong. The end result is a surprisingly simple scheduler, which requires minimal deviations from current practices (e.g., using FCFS as the basis) and behaves exactly like EASY as far as users are concerned; nevertheless, it achieves significant improvements in performance, predictability, and accuracy. Notably, this is based on a very simple runtime predictor that just averages the runtimes of the last two jobs by the same user; counterintuitively, our results indicate that using recent data is more important than mining the history for similar jobs. All the techniques suggested in this paper can be used to enhance any backfilling algorithm and are not limited to EASY.
Session Abstract
Venue: Proceedings of the 25th IEEE VLSI Test Symmposium (2007)

Memory devices have been becoming more complex with every generation and this trend will continue. Different kinds of memories present different challenges for board level test applications. This IP session will discuss several of those challenges and will introduce a new test technology proposed as IEEE P1581, offering an elegant solution to many -- if not all -- problems related to the test of the board and system level connectivity at memory device pins.
Interactive presentation: SoftSIMD - exploiting subword parallelism using source code transformations
Authors: Stefan Kraemer, Rainer Leupers, Gerd Ascheid, Heinrich Meyr
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

SIMD instructions are used to speed up multimedia applications in high performance embedded computing. Vendors often use proprietary platforms which are incompatible with others. Therefore, porting software is a very complex and time consuming task. Moreover, lots of existing embedded processors do not have SIMD extensions at all. But they do provide a wide data path which is 32-bit or wider. Usually, multimedia applications work on short data types of 8 or 16-bit. Thus, only the lower bits of the data path are used and therefore only a fraction of the available computing power is exploited for such algorithms. This paper discusses the possibility to make use of the upper bits of the data path by emulating true SIMD instructions. These instructions are implemented purely in software using a high level language such as C. Therefore, the application can be modified by making use of source code transformations which are inherently portable. The benefit of this approach is that the computing resources are used more efficiently without compromising the portability of the code. Experiments have shown that a significant speedup can be obtained by this approach.
Integration and Optimization of Multivariate Polynomials by Restriction onto a Random Subspace
Authors: Alexander Barvinok
Venue: Foundations of Computational Mathematics (2007)

We consider the problem of efficient integration of an n-variate polynomial with respect to the Gaussian measure in &#x211d;n and related problems of complex integration and optimization of a polynomial on the unit sphere. We identify a class of n-variate polynomials f for which the integral of any positive integer power fp over the whole space is well approximated by a properly scaled integral over a random subspace of dimension O(log n). Consequently, the maximum of f on the unit sphere is well approximated by a properly scaled maximum on the unit sphere in a random subspace of dimension O(log n). We discuss connections with problems of combinatorial counting and applications to efficient approximation of a hafnian of a positive matrix.
Signal modeling with non-uniform topology lattice filters
Authors: S. Krstulovic
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 200. on IEEE International Conference - Volume 02 (2001)

This article presents a new class of constrained and specialized autoregressive (AR) processes. They are derived from lattice filters where some reflection coefficients are forced to zero at a priori locations. Optimizing the filter topology allows to build parametric spectral models that have a greater number of poles than the number of parameters needed to describe their location. These NUT (non-uniform topology) models are assessed by evaluating the reduction of modeling error with respect to conventional AR models.
Probabilistic Hierarchical Face Model for Feature Localization
Authors: Feng Tang, Jin Wang, Hai Tao, Qunsheng Peng
Venue: Proceedings of the Eighth IEEE Workshop on Applications of Computer Vision (2007)

Facial feature localization is an important research area in both computer vision and pattern analysis. We present in this paper a hierarchical face model. It unifies both the global and local face appearance together with geometric information for precise feature localization. Face detection is used to obtain the face rough position and scale in the image. A coarse global AAM (Active Appearnce Model) is then applied to obtain the initial position of each part. Local detailed part-level AAM models (like the eyes, mouth) are used to refine the localization. This coarseto- fine scheme constraints the search in the correct space which makes the localization more accurate. In the partlevel localization, we consider the geometric relationship of the local parts and the global face model. The whole procedure is formulated into a Maximum-A-Posteriori(MAP) framework. Experiments demonstrate the effectiveness of our approach.
Time- and VLSI-optimal Sorting on Meshes with Multiple Broadcasting
Authors: D. Bhagavathi, H. Gurla, S. Olariu, J. Schwing, W. Shen, L. Wilson, J. Zhang
Venue: Proceedings of the 1993 International Conference on Parallel Processing - Volume 03 (1993)

In this work, we present a time-and VLSI-optimal sorting algorithm for meshes with multiple broadcasting. Specifically, we show that for every choice of a positive integer constant c, m items \left( {n^{\frac{1} {2} + \frac{1} {{2c}}}\leqslant m \leqslant n} \right) stored in the first \left\lceil {\frac{m} {{\sqrt n }}} \right\rceil columns of a mesh with multiple broadcasting of size \sqrt {n} x \sqrt {n} can be sorted in O({\frac{m} {{\sqrt n }}}) time.
An algebraic approach to reverse engineering with an application to biochemical networks
Authors: Reinhard C. Laubenbacher
Venue:  (2005)

One goal of systems biology is to predict and modify the behavior of biological networks by accurately monitoring and modeling their responses to certain types of perturbations. The construction of mathematical models based on observation of these responses, referred to as reverse engineering, is an important step in elucidating the structure and dynamics of such networks. Continuous models, described by systems of differential equations, have been used to reverse engineer biochemical networks. Of increasing interest is the use of discrete models, which may provide a conceptual description of the network. In this dissertation we introduce a discrete modeling approach, rooted in computational algebra, to reverse-engineer networks from experimental time series data. The algebraic method uses algorithmic tools, including Gr&ouml;bner-basis techniques, to build the set of all discrete models that fit time series data and to select minimal models from this set. The models used in this work are discrete-time finite dynamical systems, which, when defined over a finite field, are described by systems of polynomial functions. We present novel reverse-engineering algorithms for discrete models, where each algorithm is suitable for different amounts and types of data. We demonstrate the effectiveness of the algorithms on simulated networks and conclude with a description of an ongoing project to reverse-engineer a real gene regulatory network in yeast.
A low-overhead high-performance unified buffer management scheme that exploits sequential and looping references
Authors: Jong Min Kim, Jongmoo Choi, Jesung Kim, Sam H. Noh, Sang Lyul Min, Yookun Cho, Chong Sang Kim
Venue: Proceedings of the 4th conference on Symposium on Operating System Design & Implementation - Volume 4 (2000)

In traditional file system implementations, the Least Recently Used (LRU) block replacement scheme is widely used to manage the buffer cache due to its simplicity and adaptability. However, the LRU scheme exhibits performance degradations because it does not make use of reference regularities such as sequential and looping references. In this paper, we present a Unified Buffer Management (UBM) scheme that exploits these regularities and yet, is simple to deploy. The UBM scheme automatically detects sequential and looping references and stores the detected blocks in separate partitions of the buffer cache. These partitions are managed by appropriate replacement schemes based on their detected patterns. The allocation problem among the divided partitions is also tackled with the use of the notion of marginal gains. In both trace-driven simulation experiments and experimental studies using an actual implementation in the FreeBSD operating system, the performance gains obtained through the use of this scheme are substantial. The results show that the hit ratios improve by as much as 57.7% (with an average of 29.2%) and the elapsed times are reduced by as much as 67.2% (with an average of 28.7%) compared to the LRU scheme for the workloads we used.
Curriculum integration at the University of Alabama
Authors: K. Frair
Venue: Proceedings of the Frontiers in Education Conference, on 1995. Proceedings., 1995 - Volume 02 (1995)

The paper describes the call for systemic change in engineering education that has been issued by various groups; how that is being addressed within one Foundation Coalition (FC) member, the University of Alabama; and, in conclusion, the FC strategic planning process that has been used as part of our effort to implement change.
Maintaining bernoulli samples over evolving multisets
Authors: Rainer Gemulla, Wolfgang Lehner, Peter J. Haas
Venue: Proceedings of the twenty-sixth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2007)

Random sampling has become a crucial component of modern data management systems. Although the literature on database sampling is large, there has been relatively little work on the problem of maintaining a sample in the presence of arbitrary insertions and deletions to the underlying dataset. Most existing maintenance techniques apply either to the insert-only case or to datasets that do not contain duplicates. In this paper, we provide a scheme that maintains a Bernoulli sample of an underlying multiset in the presence of an arbitrary stream of updates, deletions, and insertions. Importantly, the scheme never needs to access the underlying multiset. Such Bernoulli samples are easy to manipulate, and are well suited to parallel processing environments. Our method can be viewed as an enhancement of the "counting sample" scheme developed by Gibbons and Matias for estimating the frequency of highly frequent items. We show how the "tracking counters" used by our maintenance scheme can be exploited to estimate population frequencies, sums, and averages in an unbiased manner, with lower variance than the usual estimators based on a Bernoulli sample. The number of distinct items in the multiset can also be estimated without bias. Finally, we discuss certain problems of subsampling and merging that a rise in systems with limited memory resources or distributed processing, respectively.
Bastille: securing Linux at a university
Authors: Jon Lasser
Venue: Proceedings of the 3rd annual conference on Atlanta Linux Showcase - Volume 3 (1999)

This paper presents a case study of a university attempting to reduce Linux-related security incidents through customizing a localized, security-aware Linux distribution based on Red Hat Linux. After describing the university environment and the parameters of the UMBC Linux project, an overview of technical and social aspects of the project is given. Following this, extensive analysis dissects the UMBC Linux 5.2 project's successes and failures, especially the failure to harness the power of the Linux community to improve the project. Finally, future development plans, including the Bastille Linux project, are briefly described.
Track Introduction: Agent Technology, Intelligent Systems and Software Computing in Management Support
Authors: Daniel R. Dolk
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

This year the Decision Technologies Track has adopted a sharper focus by targeting the emerging area of service sciences, management and engineering (SSME) as its primary application domain. SSME is a new interdisciplinary research area that synthesizes work from the reference disciplines of computer science, information sciences, operations research, industrial engineering, business strategy, management science, and social / cognitive sciences, to develop business applications that meet the challenges raised by a services-led (as opposed to a manufacturing-led) economy. Three thematic streams have been identified and implemented in the following Minitracks:
Dependence-Based Complexity Metwircs for Distributed Programs
Authors: Jingde Cheng
Venue: Proceedings of the 1993 International Conference on Parallel Processing - Volume 02 (1993)

This paper proposes some new metrics, which are defined based on various primary program dependences, for measuring complexity of distributed programs. Since different program dependences reflect different attributes of programs, the metrics can be used to measure uarious complexities of a distributed program from various viewpoints.
Dynamical Bias in the Coin Toss
Authors: Persi Diaconis, Susan Holmes, Richard Montgomery
Venue: SIAM Review (2007)

We analyze the natural process of flipping a coin which is caught in the hand. We show that vigorously flipped coins tend to come up the same way they started. The limiting chance of coming up this way depends on a single parameter, the angle between the normal to the coin and the angular momentum vector. Measurements of this parameter based on high-speed photography are reported. For natural flips, the chance of coming up as started is about .51.
Collapsar: a VM-based architecture for network attack detention center
Authors: Xuxian Jiang, Dongyan Xu
Venue: Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 (2004)

The honeypot has emerged as an effective tool to provide insights into new attacks and current exploitation trends. Though effective, a single honeypot or multiple independently operated honeypots only provide a limited local view of network attacks. Deploying and managing a large number of coordinating honeypots in different network domains will not only provide a broader and more diverse view, but also create potentials in global network status inference, early network anomaly detection, and attack correlation in large scale. However, coordinated honeypot deployment and operation require close and consistent collaboration across participating network domains, in order to mitigate potential security risks associated with each honeypot and the non-uniform level of security expertise in different network domains. It is challenging, yet desirable, to provide the two conflicting features of decentralized presence and uniform management in honeypot deployment and operation. To address these challenges, this paper presents Collapsar, a virtual-machine-based architecture for network attack detention. A Collapsar center hosts and manages a large number of high-interaction virtual honeypots in a local dedicated network. These honeypots appear, to potential intruders, as typical systems in their respective production networks. Decentralized logical presence of honeypots provides a wide diverse view of network attacks, while the centralized operation enables dedicated administration and convenient event correlation, eliminating the need for honeypot experts in each production network domain. We present the design, implementation, and evaluation of a Collapsar testbed. Our experiments with several real-world attack incidences demonstrate the effectiveness and practicality of Collapsar.
Experiments in cooperative learning: successes of an engineering novice
Authors: H. Detloff
Venue: Proceedings of the 30th Annual Frontiers in Education - Volume 01 (2000)

The results of two experiments performed over a period of four semesters demonstrate the benefits of active and cooperative classroom activities. The insights and methods provided by Project LEA/RN (Learning Enhancement Action/Resource Network) discussion groups at Iowa State University have demonstrably improved student learning in engineering classrooms. Reversing the typical roles of lecture and preparation by using preparation assignments as first exposure to course material increases student involvement with lectures and provides a means for assessing student interests and individual difficulties. The increased student preparation also raises innumerable questions for subject development; lectures become module-processing events. Other lessons learned include the value of incorporation of students with previous exposure as guides to the unfamiliar expectations of the process. The social context of cooperative learning was also improved with students less inhibited when asking questions of peers and faculty. 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
Powell-Sabin splines with boundary conditions for polygonal and non-polygonal domains
Authors: Hendrik Speleers, Paul Dierckx, Stefan Vandewalle
Venue: Journal of Computational and Applied Mathematics (2007)

Powell-Sabin splines are piecewise quadratic polynomials with a global C^1-continuity, defined on conforming triangulations. Imposing boundary conditions on such a spline leads to a set of constraints on the spline coefficients. First, we discuss boundary conditions defined on a polygonal domain, before we treat boundary conditions on a general curved domain boundary. We consider Dirichlet and Neumann conditions, and we show that a particular choice of the PS-triangles at the boundary can greatly simplify the corresponding constraints. Finally, we consider an application where the techniques developed in this paper are used: the numerical solution of a partial differential equation by the Galerkin and collocation method.