ppxscal/embedding_network huggingface dataset:
Connectivity in semialgebraic sets (abstract only)
Authors: Robert Quinn, Hoon Hong
Venue: ACM Communications in Computer Algebra (2008)

A semialgebraic set is a subset of real space defined by polynomial equations and inequalities. A semialgebraic set is a union of finitely many maximally connected components. In this talk, we consider the problem of deciding whether two given points in a semialgebraic set are connected, that is, whether the two points lie in the same connected component. In particular, we consider the semialgebraic set defined by f not equal 0 where f is a given bivariate polynomial. The motivation comes from the observation that many important/non-trivial problems in science and engineering can be often reduced to that of connectivity. Due to its importance, there has been intense research effort on the problem. We will describe a method based on gradient fields and provide a sketch of the proof of correctness based on the Morse complex. The method seems to be more efficient than the previous methods in practice.
Detecting Well-Harmonized Homeostasis in Heart Rate Fluctuations
Authors: Yuo-Hsien Shiau
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

Analyzing heart rate variability from electrocardiographic recordings has been an important method for assessing cardiovascular autonomic regulation. Researchers have conducted extensive analyses on normal as well as pathological hearts,however, it is still unclear whether increasing or decreasing the complexity of heart rate variability is a characteristic of healthy systems. In this study, we find the existence of well-harmonized homeostasisin heart rate fluctuations, in particular, the evidence is verified amongdifferent individuals including healthy subjects (n=25) and ICU patients (n=25). The methodology we used is composed of two parts, in which one is the consideration of reduction of cardiorespiratory fluctuations inherited in the original R-R intervals and the other is based upon the concept of nonlinear dynamics to construct the low-dimensional trajectory in the angle plot.In addition, we report thatthe cross-correlation measure between the theoretical angle map and the numerically derived angle trajectory can well separaterecovery (0.73$\pm$0.13) from deterioration (0.25$\pm$0.08) of ICU patients.Our results suggest that the prognostic homeostasis indexcould be valuable for clinical applications.
Temporal aggregation of equity return time-series models
Authors: W. S. Chan, S. H. Cheung, L. X. Zhang, K. H. Wu
Venue: Mathematics and Computers in Simulation (2008)

With large volatility observed in stock markets around the world over the last few years, many actuaries are now being urged to employ stochastic models to measure the solvency risk generated from insurance products with equity-linked guarantees. There are a large number of potential stochastic models for equity returns. Insurance regulators, both in Europe and North America, normally do not restrict the use of any stochastic model that reasonably fits the historical baseline data. However, in the U.S. and Canada, the final model must be calibrated to some specified distribution percentiles. The emphasis of the calibration process remains on the tails of the equity return distribution over different holding periods. In this paper, we examine the effect of temporal aggregation on classes of stochastic equity return models that are commonly used in actuarial practice. The advantages of choosing a closed (under temporal aggregation) class of processes for modelling asset returns and equity-linked guarantees are discussed. Actuarial applications of temporal aggregation using S&P500 data are given.
Synchronizer - A Web-Based Application to Enhance Capabilities of NEESCentral Web Portal
Authors: Thuy T. Le, Syeda Naema Hashmi, Kurt McMullin
Venue: Proceedings of the Seventh IEEE/ACIS International Conference on Computer and Information Science (icis 2008) (2008)

This paper discusses the development of a web-based application named Synchronizer to enhance the capability of the NEESCentral Web Portal. The NEESCentral Web Portal is a cyberinfrastructure tool available to all NEES participants and is designed to provide a simple way for researchers to share and archive their project data with NEES Repository. Synchronizer has been developed to assist multi-member projects in organizing and sharing local data with NEES Data Repository frequently. Synchronizer allows project members to connect to NEES Data Repository to download and upload data in bulk where the application automatically checks for updated files with options to replace, rename, or to keep them all. The application also allows the project administrator to put different restrictions on each project member in accessing the files and sub-directories. Synchronizer uses Mozilla Fire Fox for obtaining “GAsession ID” cookie and Internet Explorer for executing the application. The code has been developed with HTML embedded scripting language PHP, MySql open-source database, Microsoft Window Software Development Kit (Microsoft Platform SDK), GNU Wget, and Adobe Macromedia Dreamweaver web design and development tool. Users from the Pathways project have given Synchronizer very good comments.
Geometrical position tolerance assignment in reverse engineering
Authors: G. J. Kaisarlis, S. C. Diplaris, M. M. Sfantsikopoulos
Venue: International Journal of Computer Integrated Manufacturing (2008)

Geometric dimensioning and tolerancing constitutes the dominant approach for design and manufacture of mechanical parts that control inevitable dimensional and geometric deviations within appropriate limits. Position tolerance is a critical geometric tolerance very frequently used in industry. Its designation requires size data in conjunction with appropriate datums and location coordinates for the position. In reverse engineering, where typically relevant engineering information does not exist, conventional, human-based, trial and error approach for the allocation of positional tolerances requires much effort and time and offers no guarantee for the generation of the best results. This is mainly due to the large number of possible data combinations and the applicable relationships that have to be developed and processed. A methodology that aims towards the systematic solution of this problem in reasonable computing time and provides realistic and industry approved results is presented, demonstrated and discussed in the paper.
On obstructions in relation to a fixed viewpoint
Authors: K. Mulmuley
Venue: Proceedings of the 30th Annual Symposium on Foundations of Computer Science (1989)

108 Efficient, randomized algorithms are given for the following problems: (1) construction of levels of order 1 to k in an arrangement of hyperplanes in any dimension; (2) construction of higher order Voronoi diagrams of order 1 to k in any dimension; (3) hidden surface removal for completely general scenes (intersecting and curved faces are allowed). A combinatorial tool in the form of a mathematical series called a theta series is associated with a configuration of polytopes in R/sup d/. It is used to study the combinatorial, as well as algorithmic, complexity of the geometric problems under consideration.
Rank minimization via online learning
Authors: Raghu Meka, Prateek Jain, Constantine Caramanis, Inderjit S. Dhillon
Venue: Proceedings of the 25th international conference on Machine learning (2008)

Minimum rank problems arise frequently in machine learning applications and are notoriously difficult to solve due to the non-convex nature of the rank objective. In this paper, we present the first online learning approach for the problem of rank minimization of matrices over polyhedral sets. In particular, we present two online learning algorithms for rank minimization - our first algorithm is a multiplicative update method based on a generalized experts framework, while our second algorithm is a novel application of the online convex programming framework (Zinkevich, 2003). In the latter, we flip the role of the decision maker by making the decision maker search over the constraint space instead of feasible points, as is usually the case in online convex programming. A salient feature of our online learning approach is that it allows us to give provable approximation guarantees for the rank minimization problem over polyhedral sets. We demonstrate the effectiveness of our methods on synthetic examples, and on the real-life application of low-rank kernel learning.
A Dynamic Voltage Scaling Algorithm for Dynamic Workloads
Authors: Albert Mo Cheng, Yan Wang
Venue: Journal of Signal Processing Systems (2008)

Dynamic Voltage Scaling (DVS) is a promising method to achieve energy saving by slowing down the processor into multiple frequency levels in battery-operated embedded systems. However, the worst case execution time (WCET) of the tasks scheduled by DVS must be known ahead of time to ensure their schedulability. In reality, a system's workloads may change significantly without satisfying any prediction. In other words, a task's WCET may not provide useful information about its future real execution time (RET). This paper presents a novel Dynamic-Mode EDF scheduling algorithm when workloads change significantly. One of the Single-Mode, Dual-Mode, and Three-Mode frequency setting formats can be applied, based on the RET and the accumulated slack at run-time. Only one combination of the number of modes/speeds, speed-switching transition points, and the frequency scaling factor for each mode can lead to the best energy saving. Experimental results show that, given an RET pattern, our Dynamic-Mode DVS algorithm achieves an average 15% energy savings over the traditional two-mode DVS scheme on hard real-time systems. Additionally, we also consider speed-switching or energy transition overhead, and implement a preliminary test of our proposed algorithm. With a less aggressive voltage scaling strategy (fewer speed changes for each job), deadlines can still be strictly satisfied and an average of 14% energy consumption saving over a non-DVS scheme is observed.
Development of an Electroporation System for Preclinical Use
Authors: Jeong Han Yi, Hyung Sik Kim, Hong Bae Kim, Saeyoung Ahn, Youn-Suk Choi
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

Electroporation is a technique, which use micro tomilliseconds electric pulses in medicine. This pulsetechnique is based on the temporary increase of themembrane permeability due to reversible electricalbreakdown of the plasma membrane upon applicationof external high-intensity field pulses of very shortduration. Membrane charging and permeabilizationcaused by strong electric field generated by highvoltagepulses are preceded and accompanied bytransient electrode formation forces, which lead to anelongation of the cells in low-conductivity media, thusaffecting the membrane area of electropermeabilizationin response to a breakdown pulse.This paper describes a design and development ofan electroporation system with a micro-bio-chipapplicator. We have conducted electroporationexperiments in vitro using a developed system andhave found permeabilization in cell mem
Rule reduction for efficient inferencing in similarity based reasoning
Authors: Balasubramaniam Jayaram
Venue: International Journal of Approximate Reasoning (2008)

The two most important models of inferencing in approximate reasoning with fuzzy sets are Zadeh's Compositional Rule of Inference (CRI) and Similarity Based Reasoning (SBR). It is known that inferencing in the above models is resource consuming (both memory and time), since these schemes often consist of discretisation of the input and output spaces followed by computations in each point. Also an increase in the number of rules only exacerbates the problem. As the number of input variables and/or input/output fuzzy sets increases, there is a combinatorial explosion of rules in multiple fuzzy rule based systems. In this paper, given a fuzzy if-then rule base that is used in an SBR inference mechanism, we propose to reduce the number of rules by combining the antecedents of the rules that have the same consequent. We also present some sufficient conditions on the operators employed in SBR inference schemes such that the inferences obtained using the original rule base and the reduced rule base obtained as above are identical. Subsequently, these conditions are investigated and many solutions are presented for some specific SBR inference schemes.
Simulation and Measurement of On-Chip Supply Noise in Multi-Gigabit I/O Interfaces
Authors: Hai Lan, Ralf Schmitt, Chuck Yuan
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

Characteristics of the on-chip power supply noise in a 6.4Gbps serial link interface test system are analyzed by both simulation and measurement techniques. Pre- and post-layout simulation methodologies are discussed with different on-chip power grid modeling approaches proposed and supply current profile extraction method established. An on-chip supply noise measurement technique is introduced to allow monitoring both the statistics and dynamics of supply noise. Good agreement between simulation results and measurement results from the test system transmitting PRBS7 data pattern at 6.4Gbps are observed in time and frequency domain.
Location tracking of test vehicles using accelerometers
Authors: Joshua D. Jackson, Dale W. Callahan, Percy F. Wang
Venue: Proceedings of the 5th WSEAS International Conference on Circuits, Systems, Electronics, Control & Signal Processing (2006)

This paper proposes a cost effective solution to localized mobile positioning with high accuracy requirements when high grade GPS is cost excessive or unavailable. Specifically this solution is targeted for accurate position determination of test vehicles on a known stretch of bridge.
A novel knowledge discovering model for mining fuzzy multi-level sequential patterns in sequence databases
Authors: Yen-Liang Chen, Tony Cheng-Kui Huang
Venue: Data Knowledge Engineering (2008)

Items sold in a store can usually be organized into a concept hierarchy according to a taxonomy. Based on the hierarchy, sequential patterns can be found not only at the leaf nodes (individual items) of the hierarchy, but also at higher levels of the hierarchy; this is called multiple-level sequential pattern mining. In previous research, taxonomies had crisp relationships between the categories in one level and the categories in another level. In real life, however, crisp taxonomies cannot handle the uncertainties and fuzziness inherent in the relationships among items and categories. For example, the book Alice's Adventures in Wonderland can be classified into the Children's Literature category, but can also be related to the Action &Adventure category. To deal with the fuzzy nature of taxonomy, we apply fuzzy set techniques to concept taxonomies so that the relationships from one level to another can be represented by a value between 0 and 1. Accordingly, a fuzzy multiple-level mining algorithm, the fuzzy multi-level sequential mining algorithm (FMSM), is proposed to extract fuzzy multiple-level sequential patterns from databases. In addition, another algorithm, named the CROSS-FMSM algorithm, is developed to discover fuzzy cross-level sequential patterns. Experiments using synthetic datasets show the algorithms' computational efficiency and scalability, and a real dataset is used to prove the patterns' effectiveness.
Social dynamics in the age of the web
Authors: Bernardo Huberman
Venue: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia (2008)

The past decade has witnessed a momentous transformation in the way people interact and exchange information. Content is now coactively produced, shared, classified, and rated on the Web by millions of people, while attention has become an ephemeral and valuable resource that everyone seeks to acquire. This talk will describe our research on the interplay between popularity, novelty and collective attention in the Web, as well as a study of the dynamics of online opinion formation.
A topic map based framework for managing medical data in dermatology domain
Authors: Georgios Grammatikopoulos, Christos Manavis, Georgios Chaidemenos
Venue: Proceedings of the 4th WSEAS International Conference on Telecommunications and Informatics (2005)

In the context of this paper we discuss the potential use of topic maps to manage medical information, make a brief review of related attempts and consequently propose a web-based framework that incorporates topic maps technology for managing medical data in the dermatology domain. A key factor, in order to profit from the application of web technology in healthcare, it is essential to represent the way medical data is expressed and perceived in electronic form. Topic Maps as a new technology of semantic web, seems to subscribe to the satisfaction of this requirement, as they were introduced in order to build a bridge between knowledge representation and information management.
An adaptive window mechanism for image smoothing
Authors: Ardeshir Goshtasby, Martin Satter
Venue: Computer Vision and Image Understanding (2008)

Image smoothing using adaptive windows whose shapes, sizes, and orientations vary with image structure is described. Window size is increased with decreasing gradient magnitude, and window shape and orientation are adjusted in such a way as to smooth most in the direction of least gradient. Rather than performing smoothing isotropically, smoothing is performed in preferred orientations to preserve region boundaries while reducing random noise within regions. Also, instead of performing smoothing uniformly, smoothing is performed more in homogeneous areas than in detailed areas. The proposed adaptive window mechanism is tested in the context of median, mean, and Gaussian filtering, and experimental results are presented using synthetic and real images and compared with a state-of-the-art method.
Modeling korean clinical records as a simple temporal constraint satisfaction problem
Authors: Heekyong Park, Jinwook Choi
Venue: Proceedings of the 8th ACM/IEEE-CS joint conference on Digital libraries (2008)

Temporal information is especially crucial in medical text processing. The simple temporal constraint satisfaction problem (STP) has been evaluated as sufficient to represent most English clinical temporal assertions. We aimed to test expressive power of STP in representing Korean clinical documents and to find out any encoding issues dependent on Korean language. This paper shows that STP is sufficient. Some distinctive characteristics were found but they did not affect the encoding work.
Multi-dimensional limiting process for three-dimensional flow physics analyses
Authors: Sung-Hwan Yoon, Chongam Kim, Kyu-Hong Kim
Venue: Journal of Computational Physics (2008)

The present paper deals with an efficient and accurate limiting strategy for multi-dimensional compressible flows. The multi-dimensional limiting process (MLP) which was successfully proposed in two-dimensional case [K.H. Kim, C. Kim, Accurate, efficient and monotonic numerical methods for multi-dimensional compressible flows. Part II: Multi-dimensional limiting process, J. Comput. Phys. 208 (2) (2005) 570-615] is modified and refined for three-dimensional application. For computational efficiency and easy implementation, the formulation of MLP is newly derived and extended to three-dimensional case without assuming local gradient. Through various test cases and comparisons, it is observed that the newly developed MLP is quite effective in controlling numerical oscillation in multi-dimensional flows including both continuous and discontinuous regions. In addition, compared to conventional TVD approach, MLP combined with improved flux functions does provide remarkable increase in accuracy, convergence and robustness in steady and unsteady three-dimensional compressible flows.
On the difference approximation of the delay control system
Authors: S. Otakulov
Venue: Automation and Remote Control (2008)

Consideration was given to the difference approximation of the control system obeying a differential inclusion with retarded argument. Approximation of an ensemble of the trajectories of a differential inclusion by a sequence of ensembles of the trajectories of the corresponding difference (discrete) inclusions was investigated. Estimates enabling one to judge whether the approximating sequences converge were obtained. The possibility of applying the results obtained to one minimax problem of optimal control of the system under consideration was demonstrated.
Securing Grid Workflows with Trusted Computing (Extended Abstract)
Authors: Po-Wah Yau, Allan Tomlinson, Shane Balfe, Eimear Gallery
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

We propose a novel scheme that uses Trusted Computing technology to secure Grid workflows. This scheme allows the selection of trustworthy resource providers based on their platform states. The integrity and confidentiality of workflow jobs are provided using cryptographic keys that can only be accessed when resource provider platforms are in trustworthy states. In addition, platform attestation is used to detect potential workflow execution problems,and the information collected can be used for process provenance.
Register allocation for software pipelined multidimensional loops
Authors: Hongbo Rong, Alban Douillet, Guang R. Gao
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (2008)

This article investigates register allocation for software pipelined multidimensional loops where the execution of successive iterations from an n-dimensional loop is overlapped. For single loop software pipelining, the lifetimes of a loop variable in successive iterations of the loop form a repetitive pattern. An effective register allocation method is to represent the pattern as a vector of lifetimes (or a vector lifetime using Rau's terminology [Rau 1992]) and map it to rotating registers. Unfortunately, the software pipelined schedule of a multidimensional loop is considerably more complex and so are the vector lifetimes in it. In this article, we develop a way to normalize and represent the vector lifetimes, which captures their complexity, while exposing their regularity that enables a simple solution. The problem is formulated as bin-packing of the multidimensional vector lifetimes on the surface of a space-time cylinder. A metric, called distance, is calculated either conservatively or aggressively to guide the bin-packing process, so that there is no overlapping between any two vector lifetimes, and the register requirement is minimized. This approach subsumes the classical register allocation for software pipelined single loops as a special case. The method has been implemented in the ORC compiler and produced code for the IA-64 architecture. Experimental results show the effectiveness. Several strategies for register allocation are compared and analyzed.
Distance learning education using the web
Authors: Shakil Akhtar, Mudasser F. Wyne
Venue: Proceedings of the 10th WSEAS International Conference on APPLIED MATHEMATICS (2006)

This paper discusses the various distance learning techniques for the web. The fundamental concepts of distance learning and relevant technologies, such as videoconferencing, audio conferencing, online courses, web conferencing, and print media are discussed. Implementation examples using Internet for distance education are highlighted thru examples.