ppxscal/embedding_network huggingface dataset:
Interprocedural analysis of asynchronous programs
Authors: Ranjit Jhala, Rupak Majumdar
Venue: Proceedings of the 34th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages (2007)

An asynchronous program is one that contains procedure calls which are not immediately executed from the callsite, but stored and "dispatched" in a non-deterministic order by an external scheduler at a later point. We formalize the problem of interprocedural dataflow analysis for asynchronous programs as AIFDS problems, a generalization of the IFDS problems for interprocedural dataflow analysis. We give an algorithm for computing the precise meet-over-valid-paths solution for any AIFDS instance, as well as a demand-driven algorithm for solving the corresponding demand AIFDS instances. Our algorithm can be easily implemented on top of any existing interprocedural dataflow analysis framework. We have implemented the algorithm on top of BLAST, thereby obtaining the first safety verification tool for unbounded asynchronous programs. Though the problem of solving AIFDS instances is EXPSPACE-hard, we find that in practice our technique can efficiently analyze programs by exploiting standard optimizations of interprocedural dataflow analyses.
Design of a Framework for Handling Security Issues in Grids
Authors: Sarbjeet Singh, Seema Bawa
Venue: Proceedings of the 9th International Conference on Information Technology (2006)

Grid Computing has emerged as core computing technology in many distributed applications initiated by different organizations all over the world. It aims to enable large scale resource sharing. Security is a big and challenging issue as a grid service may impact number of other services/resources distributed over wide area networks. The dynamic and multiinstitutional nature of grid applications introduces challenging security issues that require new technical approaches. This paper proposes, at an abstract level, a framework for handling security issues in grids. The framework is capable of addressing both, generic as well as application specific security issues of grid services.
Protecting file systems with transient authentication
Authors: Mark D. Corner, Brian D. Noble
Venue: Wireless Networks (2005)

Laptops are vulnerable to theft, greatly increasing the likelihood of exposing sensitive files. Unfortunately, storing data in a cryptographic file system does not fully address this problem. Such systems ask the user to imbue them with long-term authority for decryption, but that authority can be used by anyone who physically possesses the machine. Forcing the user to frequently reestablish his identity is intrusive, encouraging him to disable encryption.This tension between usability and security is eliminated through Transient Authentication, in which a small hardware token continuously authenticates the user's presence to the laptop over a short-range, wireless link. Whenever the laptop needs decryption authority, it acquires it from the token; authority is retained only as long as necessary. With careful key management, ZIA imposes an overhead of less than 7% for representative workloads, though some infrequent operations suffer greater overheads. The largest file cache on our hardware can be re-encrypted within five seconds of the user's departure, and restored in just over six seconds after detecting the user's return. This secures the machine before an attacker can gain physical access, but recovers full performance before a returning user resumes work. Key granularity plays an important role in determining performance; assigning encryption keys on a per-directory basis limits the cost of an exposed key while maintaining acceptable overhead.
Boundary Element Method-Based Scattered Feature Interpolation Algorithm in the Analysis of LV Deformation
Authors: Ping Yan, Albert Sinusas, James S. Duncan
Venue: Proceedings of the 2006 Conference on Computer Vision and Pattern Recognition Workshop (2006)

The quantification of left ventricular (LV) deformation from noninvasive image sequences is an important clinical problem. The accurate estimation of this information is often hindered by the following factors: i.) the imagederived features are found at sparse and unevenly sampled spatial positions; ii.) the currently available algorithms for interpolating features have tradeoffs related to accuracy, lattice density, physical plausibility and computation time. This paper introduces a new interpolation algorithm based on Boundary Element Method (BEM). By Comparing with more standard B-Spline based interpolation method: Free Form Deformation (FFD) with different lattice density, this new algorithm is more accurate and physically plausible, however, doesn't lose the computational efficiency. We then employ the BEM-based interpolation algorithm with the Generalized Robust Point Matching (GRPM) to derive the dense displacement fields from 3D LV image sequences. The approach is evaluated on 4 in-vivo cardiac magnetic resonance image sequences. The results are compared to the displacements found in implanted markers, used as a gold standard.
An image-based calibration technique of spatial domain depth-from-defocus
Authors: Soon-Yong Park
Venue: Pattern Recognition Letters (2006)

Depth-from-defocus (DFD) is useful in 3-D range image acquisition and automatic focusing. However, DFD needs precise calibration of internal camera parameters. Most DFD techniques use well known camera calibration techniques or specially designed vision systems to precisely measure the settings of the lens system of a camera. In this paper, we introduce an image-based defocus calibration technique. Especially we employ the Spatial domain Convolution/Deconvolution Transform Method (STM) which is introduced by Subbarao and Surya [Subbarao, M., Surya, G., 1994. Depth-from-defocus: A spatial domain approach. Internat. J. Comput. Vision 13 (3), 271-294]. STM estimates blur parameters @s"1 and @s"2 of defocused images obtained at two different lens steps of the camera. In STM, the blur difference between two defocused images is considered to be a constant value which is determined by internal camera parameters. We use the blur level of the defocused images to calibrate blur difference and camera parameters. Calibrated parameters yield consistent results in depth estimation. Experimental results of depth measurement using real objects are presented.
A Time-Series Data Analyzing System Using a New Time-Frequency Transform
Authors: Yih-Nen Jeng, You-Chi Cheng
Venue: Proceedings of the First International Conference on Innovative Computing, Information and Control - Volume 1 (2006)

A new time-frequency transform, whose resulting spectrogram has the best frequency resolution among that of existing transforms, is employed to construct a simple system of data acquisition and analysis. The transform employs an iterative and diffusive filter to remove the non-sinusoidal part. The spectrum of the sinusoidal part is evaluated by a strategy involving a Fast Fourier Transform (FFT). By imposing a Gaussian window centered at a given frequency on the spectrum, a band-passed data is obtained which is just the corresponding mode or real part of the transform. Finally, the corresponding amplitude is obtained via the Hilbert transform. A commercial microphone plugged into a notebook computer properly equipped with necessary software and the transform form a complete portable system. Two tests show that the system is a new tool to look into detailed information of a complicated data string formed from a single or multiple sources.
Using packet probes for available bandwidth estimation: a wireless testbed experience
Authors: Mesut Ali Ergin, Marco Gruteser
Venue: Proceedings of the 1st international workshop on Wireless network testbeds, experimental evaluation characterization (2006)

Evaluating available bandwidth estimation methods requires a malleable MAC protocol implementation, precise MAC layer packet timing measurements, and the ability to create control topologies in laboratory setups so that not all nodes are within communication range. To address these challenges,we have exploited IEEE 802.11e-derived features to obtain more control over the MAC layer operation of off-the-shelf radios and implemented a measurement-system that uses CPU timestamp counter and radio hardware timestamps to monitor MAC activity with microsecond resolution. In addition to presenting performance of our available bandwidth estimation method using packet probes, we also discuss solutions and open issues to provide useful information for other testbed cross-layer protocol evaluations, which are likely to face similar challenges.
Commercial applications of agents: lessons, experiences and challenges
Authors: Roxana A. Belecheanu, Steve Munroe, Michael Luck, Terry Payne, Tim Miller, Peter McBurney, Michal Pěchouček
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

As has been argued very eloquently and effectively, there is a chasm that needs to be crossed in the adoption of any new technology [8], and the marketing of such technologies must somehow try to bridge the gap that arises. Many currently see agent technologies in the middle of that chasm period of adoption, where addressing the visionaries as well as the pragmatists (or early adopters) who avoid risks but readily see the advantages of tested technologies [11], is necessary. As part of the needed marketing exercise, we believe that a catalogue of case studies of deployed applications with real quantified business benefit, can help convince those wavering pragmatists. Perhaps more importantly, the lessons that can be drawn from such case studies may also be used to guide the efforts of new commercial agent technology providers, both in developing the technology itself, and in understanding the concerns and constraints of early adopters.
New conditions for global exponential stability of cellular neural networks with delays
Authors: Hongyong Zhao, Jinde Cao
Venue: Neural Networks (2005)

In this paper, we study further a class of cellular neural networks model with delays. By employing the inequality a@?k=1mb"k^q^"^k@?1r@?k=1mq"kb"k^r+1ra^r(a>=0,b"k>=0,q"k>0with@?k=1mq"k=r-1,andr>1), constructing a new Lyapunov functional, and applying the Homeomorphism theory, we derive some new conditions ensuring the existence, uniqueness of the equilibrium point and its global exponential stability for cellular neural networks. These conditions are independent of delays and posses infinitely adjustable real parameters, which are of highly important significance in the designs and applications of networks. In addition, we extend or improve the previously known results.
Prosody-driven Sentence Processing: An Event-related Brain Potential Study
Authors: Ann Pannekamp, Ulrike Toepel, Kai Alter, Anja Hahne, Angela D. Friederici
Venue: Journal of Cognitive Neuroscience (2005)

Four experiments systematically investigating the brain's response to the perception of sentences containing differing amounts of linguistic information are presented. Spoken language generally provides various levels of information for the interpretation of the incoming speech stream. Here, we focus on the processing of prosodic phrasing, especially on its interplay with phonemic, semantic, and syntactic information. An event-related brain potential (ERP) paradigm was chosen to record the on-line responses to the processing of sentences containing major prosodic boundaries. For the perception of these prosodic boundaries, the so-called closure positive shift (CPS) has been manifested as a reliable and replicable ERP component. It has mainly been shown to correlate to major intonational phrasing in spoken language. However, to define this component as exclusively relying on the prosodic information in the speech stream, it is necessary to systematically reduce the linguistic content of the stimulus material. This was done by creating quasi-natural sentence material with decreasing semantic, syntactic, and phonemic information (i. e., jabberwocky sentences, in which all content words were replaced by meaningless words; pseudoword sentences, in which all function and all content words are replaced by meaningless words; and delexicalized sentences, hummed intonation contour of a sentence removing all segmental content). The finding that a CPS was identified in all sentence types in correlation to the perception of their major intonational boundaries clearly indicates that this effect is driven purely by prosody.
A Preliminary Study of Respiratory Variations in the Photoplethysmogram during Lower Body Negative Pressure
Authors: Suzanne Wendelken, Stephen Linder, Sue McGrath
Venue: Proceedings of the 19th IEEE Symposium on Computer-Based Medical Systems (2006)

Previous studies have shown that the photoplethysmogram (PPG) may be a useful tool for the noninvasive detection of hypovolemia. The focus has been on determining if frequency analysis of the respiratory induced variations of the PPG can be used as an indicator of blood volume. In this preliminary study, we evaluate these frequency analysis techniques for two subjects undergoing Lower Body Negative Pressure (LBNP) induced hypovolemia. Using Matlab®-based software the power of the respiratory component and heart rate component were calculated using the periodogram method for spectral estimation. Consistent with other studies our algorithms were able to automatically detect changes in the respiratory variations. We found a significant increase in the respiratory variations in the PPG during simulated hypovolemia. By taking the ratio of the respiratory power to the heart rate power we consistently detected hypovolemia in subjects corresponding to sequestration of approximately 2 liters of blood (LBNP >70 mm Hg). The increase in this ratio occurred before significant change in blood pressure or tachycardia were observed.
Average LCR and AFD for SC Diversity Over Correlated Weibull Fading Channels
Authors: Joy Iong-Zong Chen
Venue: Wireless Personal Communications: An International Journal (2006)

The analytic methods of average LCR (Level Crossing Rate) and AFD (Average Fading Duration) are applied in the analysis for the SC (Selection Combining) diversity, which works over the correlated Weibull statistics channel. The dual branch SC diversity was used to prove the accuracy of the derived theoretical formula in this paper. We adopt different probability density functions (pdf) and cumulate distribution functions (CDF) to show the Moreover, the numerical results obtained from computer are verified to the published researches.
Analysis of Spatially and Temporally Overlapping Events with Application to Image Sequences
Authors: Guillermo Ayala, Rafael Sebastian, Maria Elena Diaz, Ester Diaz, Roberto Zoncu, Derek Toomre
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2006)

Counting spatially and temporally overlapping events in image sequences and estimating their shape-size and duration features are important issues in some applications. We propose a stochastic model, a particular case of the nonisotropic 3D Boolean model, for performing this analysis: the temporal Boolean model. Some probabilistic properties are derived and a methodology for parameter estimation from time-lapse image sequences is proposed using an explicit treatment of the temporal dimension. We estimate the mean number of germs per unit area and time, the mean grain size and the duration distribution. A wide simulation study in order to assess the proposed estimators showed promising results. The model was applied on biological image sequences of in-vivo cells in order to estimate new parameters such as the mean number and duration distribution of endocytic events. Our results show that the proposed temporal Boolean model is effective for obtaining information about dynamic processes which exhibit short-lived, but spatially and temporally overlapping events.
The impact of internet banking on banks: a descriptive and evaluative case study of a large united states bank (lusb)
Authors: Clifford Butler
Venue:  (2006)

Banks have adopted Internet Banking during the past ten years. This descriptive and evaluative case study examined the adoption of Internet banking in six large banks and in one small bank in the northeastern states of U.S. The study surveyed the quality of service (QoS) of the websites of the banks that participated in the study with special emphasis to one large bank (LUSB). This study utilized a positivist methodology to investigate the phenomenon of Internet banking adoption and its impact on the core retail banking business. Internet banking strategies were aligned with the banks' core business based on the data from this study. The data from the study did not support the perception that Internet banking had adverse impact on retail banking. The study further investigated in detail the perception and extent to which Internet banking affected the financial performance, stakeholder value, internal processes, and intangible assets of one large bank. Online security and privacy were important to all banks and collecting of customer information was minimal. The banks in the study operationalized their Internet banking as a bundled centralized service rather than a distributed service. Adoption of emerging technologies such as, wireless and mobile services was still a low priority in both the large and small banks in the study.
Rule interestingness analysis using OLAP operations
Authors: Bing Liu, Kaidi Zhao, Jeffrey Benkler, Weimin Xiao
Venue: Proceedings of the 12th ACM SIGKDD international conference on Knowledge discovery and data mining (2006)

The problem of interestingness of discovered rules has been investigated by many researchers. The issue is that data mining algorithms often generate too many rules, which make it very hard for the user to find the interesting ones. Over the years many techniques have been proposed. However, few have made it to real-life applications. Since August 2004, we have been working on a major application for Motorola. The objective is to find causes of cellular phone call failures from a large amount of usage log data. Class association rules have been shown to be suitable for this type of diagnostic data mining application. We were also able to put several existing interestingness methods to the test, which revealed some major shortcomings. One of the main problems is that most existing methods treat rules individually. However, we discovered that users seldom regard a single rule to be interesting by itself. A rule is only interesting in the context of some other rules. Furthermore, in many cases, each individual rule may not be interesting, but a group of them together can represent an important piece of knowledge. This led us to discover a deficiency of the current rule mining paradigm. Using non-zero minimum support and non-zero minimum confidence eliminates a large amount of context information, which makes rule analysis difficult. This paper proposes a novel approach to deal with all of these issues, which casts rule analysis as OLAP operations and general impression mining. This approach enables the user to explore the knowledge space to find useful knowledge easily and systematically. It also provides a natural framework for visualization. As an evidence of its effectiveness, our system, called Opportunity Map, based on these ideas has been deployed, and it is in daily use in Motorola for finding actionable knowledge from its engineering and other types of data sets.
A new synthetic web server trace generation methodology
Authors: S. Weber, R. Hariharan
Venue: Proceedings of the 2003 IEEE International Symposium on Performance Analysis of Systems and Software (2003)

We propose a new synthetic trace generation methodology for web server performance benchmarking. We discuss the two primary existing approaches to synthetic trace generation in terms of queueing models. We propose a new methodology as the natural combination of these two approaches. This hybrid approach permits natural modeling of client content and server session caching as well as a natural correspondence between the workload model parameters and the statistics of the resulting synthetic trace.
Detail sculpting using cubical marching squares
Authors: Chien-Chang Ho, Cheng-Han Tu, Ming Ouhyoung
Venue: Proceedings of the 2005 international conference on Augmented tele-existence (2005)

The demand for customizing models is increasing rapidly, but the related techniques for sculpting in the volumetric form raise several issues that need to be addressed. These issues include preserving sharp features, inter-cell independency, maintaining consistent topology, and adaptive resolution. These issues affect the quality of resulting shapes and the execution speed while manipulating models. Traditionally, marching cubes algorithm provides satisfactory performance for visualizing volume data in sculpting applications. However, sharp features, which are important characteristics of models, are lost while using marching cubes to visualize the resulting volume data. Furthermore, we need to perform crack patching operations to fill up the gaps between different resolutions in adaptive resolution. In contrast, these issues could be easily fulfilled by replacing the underlying isosurfacing algorithm with cubical marching squares algorithm. In this paper, we propose data structures for storing volume data and methods for Boolean operations to manipulate these data. We archive highly detailed models while sculpting at interactive speed by using proposed data structures and methods in conjunction with cubical marching squares algorithm.
Opportunistic scheduling: generalizations to include multiple constraints, multiple interfaces, and short term fairness
Authors: Sunil Suresh Kulkarni, Catherine Rosenberg
Venue: Wireless Networks (2005)

We consider several scheduling problems for packet based systems with time-varying channel conditions. Designing scheduling mechanisms that take advantage of time-varying channel conditions, which are different for different users, is necessary to improve system performance; however this has to be done in a way that provides some level of fairness among the users. Such scheduling mechanisms are termed opportunistic. We generalize the opportunistic scheduling mechanisms in the literature on three fronts. First, we formulate and solve an opportunistic scheduling problem with multiple general long term QoS constraints and a general system objective function. The solution of this opportunistic scheduling problem is an index policy. Then, we generalize this problem to include multiple interface systems in which several users can be served simultaneously. Apart from the long term QoS constraints specified by each user, multiple interface systems are constrained with other physical limitations imposed by the system. We show that the structure of the optimal opportunistic scheduling policy is carried over to the problem with general constraints and multiple interfaces. We also study the stability of the multiple interface systems and propose a throughput optimal scheduling rule for such systems. We then formulate an opportunistic scheduling problem with short term processor sharing fairness constraints as an optimization problem where fairness is guaranteed over a finite time window. In its most general form, this problem cannot be solved analytically. Hence observing the form of the optimal policies for special cases, we propose a heuristic scheduling policy. We illustrate the effectiveness of the policies via simulation.
Polynomial first integrals via the Poincaré series
Authors: Jaume Giné
Venue: Journal of Computational and Applied Mathematics (2005)

In (Appl. Math. 28 (2001) 17) a method to compute the Poincaré-Liapunov constants for an arbitrary analytic differential system which has a linear center at the origin in function of the coefficients of the system was given. This method also computes the coefficients of the Poincaré series in function of the same coefficients. In this work we use this method to determine polynomial differential systems which have a polynomial first integral.