ppxscal/embedding_network huggingface dataset:
Tip-to-Tail Scramjet Simulation with Plasma-Assisted Control
Authors: Datta V. Gaitonde, Eswar Josyula
Venue: Proceedings of the 2004 Users Group Conference (2004)

A prominent pacing item in the quest for sustained hypersonic flight, and affordable access-to-space capability, is the development of an efficient air-breathing propulsion system. Key barriers of fluid dynamic origin includes, high thermal loads, shock/boundary layer interactions (SBLI) and fuel-air mixing at high-speeds, among other, all of which significantly degrade propulsion efficiency. One approach towards alleviating or eliminating these andother problems, and to provide a crucial energy management function, is to employ electromagnetic fields to control the relatively high temperature, low pressure environment encountered in proposed flight envelopes. To this end, several aspects of magnetogasdynamic (MGD) assisted scramjet flowpaths have been simulated using three-dimensional, integrated, multidisciplinary models requiring the large-scale resources available through the High Performance Computing Modernization Program (HPCMP). In this paper, we describe the complex flow field encountered in a scramjet and its control at various electromagnetic parameters. Among the key conclusions derived from these high-fidelity simulations are the limiting nature of separation and vortical structure formation on MGD generator operation and the deleterious effects of Hall currents, which induce non-intuitive system level asymmetries. Efforts have also focused on obtaining computationally intensive first-principles solutions for various high-temperature effects where phenomenological models have failed. Results from one of these, the modeling of detailed state-to-state kinetics of oxygen and nitrogen mixtures, is described, with emphasis on the derived insight into the phenomenon of vibrational freezing in nozzles, which is a key factor in loss of scramjet propulsion efficiency.
A Corrected Proof of the Stochastic Verification Theorem within the Framework of Viscosity Solutions
Authors: Fausto Gozzi, Andrzej Swiech, Xun Yu Zhou
Venue: SIAM Journal on Control and Optimization (2005)

We present a full and corrected proof of the stochastic verification theorem that was first obtained by Zhou, Yong, and Li [SIAM J. Control Optim., 35 (1997), pp. 243--253].
Algebraic Power Analysis by Abstract Interpretation
Authors: Isabella Mastroeni
Venue: Higher-Order and Symbolic Computation (2004)

In this paper we design abstract domains for power analysis. These domains are conceived to discover properties of the following type: "The variable X at a given program point is the power of c with the exponent having a given property ¿," where c and ¿ are automatically determined. This construction is general and includes different algebraic entities, such as numerical and polynomial (with rational coefficients), as bases. Several families of domains are presented, some of these consider that the exponent can be any natural or integer value, the others also include the analysis of properties of the exponent set. Relevant lattice-theoretic properties of these domains are proved such as the absence of infinite ascending chain and the structure of their meet-irreducible elements. The numerical domains are applied in the analysis of integer powers of imperative programs and in the analysis of probabilistic concurrent programming, with probabilistic non-deterministic choice. Moreover we use the numerical power domains in order to analyze the factorization of integer variables, i.e., invariant properties of factors and of their exponents. In this way we are able to statically detect information hidden in prime factorization, which can be used in software watermarking.
An approach of composing near optimal invalidation reports
Authors: Meng Su, Chih-Fang Wang, Wen-Chi Hou
Venue: Proceedings of the 6th international conference on Mobile data management (2005)

Caching can reduce expensive data transfers and improve the performance of mobile computing. In order to reuse caches after short disconnections, invalidation reports are broadcast to clients to identify outdated items. Detailed reports may not be desirable because they can consume too much bandwidth. On the other hand, false invalidations may set in if the accurate timing of updates is not provided. In this research, we aim to reduce the false invalidation rates of cached items. Based on our analysis, false invalidation rates are closely related to clients' reconnection patterns (i.e., the distribution of the time spans between disconnections and reconnections). We show that in theory for any given reconnection pattern, a report with a minimal false invalidation rate can be derived. For practical uses, we propose to capture the reconnection pattern by sampling and develop a method to compose a near-optimal invalidation report. This method is simple and fast. Experimental results have confirmed that our method is indeed more effective in reducing the false invalidation rate than others.
Databases in Virtual Organizations: a collective interview and call for researchers
Authors: Marianne Winslett
Venue: ACM SIGMOD Record (2005)

When the Databases in Virtual Organizations (DIVO) workshop convened after SIGMOD 2004 in Paris, many of us attending weren't sure what a virtual organization was, much less what relevance it could have to database research. Five hours later, as the lights snapped off in the rest of the building and the maintenance crew hovered patiently outside our meeting room, we had become a group with a mission: to let the database research community know what an incredible idea generator and testbed virtual organizations could be for research on information integration and data security.
IMAX: Incremental Maintenance of Schema-Based XML Statistics
Authors: Maya Ramanath, Lingzhi Zhang, Juliana Freire, Jayant R. Haritsa
Venue: Proceedings of the 21st International Conference on Data Engineering (2005)

Current approaches for estimating the cardinality of XML queries are applicable to a static scenario wherein the underlying XML data does not change subsequent to the collection of statistics on the repository. However, in practice, many XML-based applications are dynamic and involve frequent updates to the data. In this paper, we investigate efficient strategies for incrementally maintaining statistical summaries as and when updates are applied to the data. Specifically, we propose algorithms that handle both the addition of new documents as well as random insertions in the existing document trees. We also show, through a detailed performance evaluation, that our incremental techniques are significantly faster than the naive recomputation approach; and that estimation accuracy can be maintained even with a fixed memory budget.
EUFID description: Systems Development Corporation
Authors: Margie Templeton
Venue: Issue 79 (January 1982) (1982)

EUFID (End User Friendly Interface to Database) is designed to be used as an independent front end to diverse database and data management systems. The main EUFID modules are application and data management system (DMS) independent. The analyzer parses the English question using a dictionary that is specific to the database. The dictionary defines the underlying concept of the English words in terms of the other words in the sentence and the location of the word with respect to the other words. The parsing is done using the semantic dictionary plus English syntax rules which are built into the analyzer. The analyzer builds a concept tree which is sent to the mapper. The mapper maps the concept tree, which contains concepts in the user's view of the database, into the groups and fields of the database. The mapper produces a query in Intermediate Language (IL) which is a relational language. The IL query for any DMS will be identical. A specific translator for a DMS then translates the IL into the query language for the data management system. Currently, translators exist for INGRES, a relational DMS, and WWDMS, a network DMS with procedural queries. Three different applications have been developed, one which runs under WWDMS and two which run under INGRES.
Robust Information Dissemination in Uncooperative Environments
Authors: Seung Jun, Mustaque Ahamad, Jun (Jim) Xu
Venue: Proceedings of the 25th IEEE International Conference on Distributed Computing Systems (2005)

The open nature of peer-to-peer systems has played an important role in their growing popularity. The current file-sharing applications, for instance, have been widely used largely because they allow anyone to participate in them. This openness, however, brings up new issues because selfish, malicious, faulty, compromised, or resource-constrained peers may degrade a system. We explore the case for large-scale information dissemination through the design of the Trust-Aware Multicast (TAM) protocol. Nodes in TAM can exhibit uncooperative behavior such as delaying, discarding, modifying, replaying, and fabricating messages. While detecting such behaviors, TAM computes a level of trust for each node and adapts the underlying multicast tree according to trustworthiness of nodes, which leads to performance improvement in the system. The results from our simulation and PlanetLab experiments show that even with a significant portion of nodes being uncooperative, TAM is able to build a stable dissemination tree that provides lower message delay to well-behaved nodes.
Compliant grasping with passive forces
Authors: Cai-Hua Xiong, Michael Yu Wang, Yong Tang, You-Lun Xiong
Venue: Journal of Robotic Systems (2005)

Because friction is central to robotic grasp, developing an accurate and tractable model of contact compliance, particularly in the tangential direction, and predicting the passive force closure are crucial to robotic grasping and contact analysis. This paper analyzes the existence of the uncontrollable grasping forces (i.e., passive contact forces) in enveloping grasp or fixturing, and formulates a physical model of compliant enveloping grasp. First, we develop a locally elastic contact model to describe the nonlinear coupling between the contact force with friction and elastic deformation at the individual contact. Further, a set of &ldquo;compatibility&rdquo; equations is given so that the elastic deformations among all contacts in the grasping system result in a consistent set of displacements of the object. Then, combining the force equilibrium, the locally elastic contact model, and the &ldquo;compatibility&rdquo; conditions, we formulate the natural compliant model of the enveloping grasp system where the passive compliance in joints of fingers is considered, and investigate the stability of the compliant grasp system. The crux of judging passive force closure is to predict the passive contact forces in the grasping system, which is formulated into a nonlinear least square in this paper. Using the globally convergent Levenberg-Marquardt method, we predict contact forces and estimate the passive force closure in the enveloping grasps. Finally, a numerical example is given to verify the proposed compliant enveloping grasp model and the prediction method of passive force closure. &copy; 2005 Wiley Periodicals, Inc.
More Web Services Notifications
Authors: Steve Vinoski
Venue: IEEE Internet Computing (2004)

In the March/April issue of IEEE Internet Computing, I wrote about several Web Services specifications that define facilities and approaches required to support notification-based and event-driven systems. I had not intended to write a two-part column series. However, just after I finished that column, a group of companies, including Hewlett-Packard and IBM,published their WS-Notification specifications. Since then, several readers have asked why I didn't include these new specifications, so I've decided to cover them here.
LAD: Localization Anomaly Detection forWireless Sensor Networks
Authors: Wenliang Du, Lei Fang, Peng Ning
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Papers - Volume 01 (2005)

In wireless sensor networks (WSNs), sensors' locations play a critical role in many applications. Having a GPS receiver on every sensor node is costly. In the past, a number of location discovery (localization) schemes have been proposed. Most of these schemes share a common feature: they use some special nodes, called beacon nodes, which are assumed to know their own locations (e.g., through GPS receivers or manual configuration). Other sensors discover their locations based on the reference information provided by these beacon nodes. Most of the beacon-based localization schemes assume a benign environment, where all beacon nodes are supposed to provide correct reference information. However, when the sensor networks are deployed in a hostile environment, where beacon nodes can be compromised, such an assumption does not hold anymore. In this paper, we propose a general scheme to detect localization anomalies that are caused by adversaries. Our scheme is independent from the localization schemes. We formulate the problem as an anomaly intrusion detection problem, and we propose a number of ways to detect localization anomalies. We have conducted simulations to evaluate the performance of our scheme, including the false positive rates, the detection rates, and the resilience to node compromises.
Convertible Undeniable Partially Blind Signatures
Authors: Zhenjie Huang, Zhixiong Chen, Yumin Wang
Venue: Proceedings of the 19th International Conference on Advanced Information Networking and Applications - Volume 1 (2005)

This paper extends the concept of partially blind signature to the convertible undeniable partially blind signature, in which only the signer can verify and confirm the validity of given signatures and convert given signatures into universally verifiable signatures, along with a formal definition for it and a practical scheme that implements it. The proposed scheme is efficient and secure, in which its unforgeability is the same as that of the Schnorrýs signature scheme and its untransferability relies on the hardness of Decision Diffie-Hellman Problem.
Extending the ONESAF Testbed into a C4ISR Testbed
Authors: Joseph A. Giampapa, Katia Sycara, Sean Owens, Robin Glinton, Young-Woo Seo, Bin Yu, Charles E. Grindle, Michael Lewis
Venue: Simulation (2004)

This article describes how the modeling and simulation environment of the OneSAF Testbed Baseline (OTB) v1.0 has been extended to enable the testing of heterogeneous algorithms that are being designed for real-world C4ISR applications. This has been accomplished by building an architecture that extends functional and logical components of the OTB system in the following ways: the use of the OTB Compact Terrain Database for terrain analysis and preliminary threat assessment, the addition of the RETSINA-OTB Bridge for the real-time query and control of OTB entities, and the addition of new DIS-based sensor entities for interoperation with Command and Control algorithms, to name a few. This article illustrates how to make a few small but general extensions to a modeling and simulation system to create a larger testbed system with minimum impact on the native system and with great potential for the range of applications that can exploit it.
Face Recognition Based on Frontal Views Generated from Non-Frontal Images
Authors: Volker Blanz, Patrick Grother, P. Jonathon Phillips, Thomas Vetter
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

This paper presents a method for face recognition across large changes in viewpoint. Our method is based on a Morphable Model of 3D faces that represents face-specific information extracted from a dataset of 3D scans. For non-frontal face recognition in 2D still images, the Morphable Model can be incorporated in two different approaches: In the first, it serves as a preprocessing step by estimating the 3D shape of novel faces from the non-frontal input images, and generating frontal views of the reconstructed faces at a standard illumination using 3D computer graphics. The transformed images are then fed intostate-of-the-art face recognition systems that are optimized for frontal views. This method was shown to be extremely effective in the Face Recognition Vendor Test FRVT 2002. In the process of estimating the 3D shape of a face from an image, a set of model coefficients are estimated. In the second method, face recognition is performed directly from these coefficients. In this paper we explain the algorithm used to preprocess the images in FRVT 2002, present additional FRVT 2002 results, and compare these results to recognition from the model coefficients.
MER-DIMES: A Planetary Landing Application of Computer Vision
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

During the Mars Exploration Rover (MER) landings, the Descent Image Motion Estimation System (DIMES) was used for horizontal velocity estimation. The DIMES algorithm combined measurements from a descent camera, a radar altimeter, and an inertial measurement unit. To deal with large changes in scale and orientation between descent images, the algorithm used altitude and attitude measurements to rectify images to a level ground plane. Feature selection and tracking were employed in the rectified images to compute the horizontal motion between images. Differences of consecutive motion estimates were then compared to inertial measurements to verify correct feature tracking. DIMES combined sensor data from multiple sources in a novel way to create a low-cost, robust, and computationally efficient velocity estimation solution, and DIMES was the first use of computer vision to control a spacecraft during planetary landing. This paper presents the detailed implementation of the DIMES algorithm and the results from the two landings on Mars.
Optimizing Linux(R) Performance: A Hands-On Guide to Linux(R) Performance Tools
Authors: Phillip G. Ezolt
Venue:  (2005)

The first comprehensive, expert guide for end-to-end Linux application optimization Learn to choose the right tools-and use them together to solve real problems in real production environmentsSuperior application performance is more crucial than ever-and in today's complex production environments, it's tougher to ensure, too. If you use Linux, you have extraordinary advantages: complete source code access, plus an exceptional array of optimization tools. But the tools are scattered across the Internet. Many are poorly documented. And few experts know how to use them together to solve real problems. Now, one of those experts has written the definitive Linux tuning primer for every professional: Optimizing Linux® Performance.Renowned Linux benchmarking specialist Phillip Ezolt introduces each of today's most important Linux optimization tools, showing how they fit into a proven methodology for perfecting overall application performance. Using realistic examples, Ezolt shows developers how to pinpoint exact lines of source code that are impacting performance. He teaches sysadmins and application developers how to rapidly drill down to specific bottlenecks, so they can implement solutions more quickly. You'll discover how to: Identify bottlenecks even if you're not familiar with the underlying system Find and choose the right performance tools for any problem Recognize the meaning of the events you're measuring Optimize system CPU, user CPU, memory, network I/O, and disk I/O-and understand their interrelationships Fix CPU-bound, latency-sensitive, and I/O-bound applications, through case studies you can easily adapt to your own environmentInstall and use oprofile, the advanced systemwide profiler for Linux systemsIf you're new to tuning, Ezolt gives you a clear and practical introduction to all the principles and strategies you'll need. If you're migrating to Linux, you'll quickly master Linux equivalents to the tools and techniques you already know. Whatever your background or environment, this book can help you improve the performance of all your Linux applications-increasingbusiness value and user satisfaction at the same time.© Copyright Pearson Education. All rights reserved.
Sub-document queries over XML with XSQirrel
Authors: Arnaud Sahuguet, Bogdan Alexe
Venue: Proceedings of the 14th international conference on World Wide Web (2005)

This paper describes XSQirrel, a new XML query language that transforms a document into a sub-document, i.e. a tree where the root-to-leaf paths are a subset of the root-to-leaf paths from the original document.We show that this type of queries is extremely useful for various applications (e.g. web services) and that the currently existing query languages are poorly equipped to express, reason and evaluate such queries. In particular, we emphasize the need to be able to compose such queries. We present the XSQirrel language with its syntax, semantics and two language specific operators, union and composition.For the evaluation of the language, we leverage well established query technologies by translating XSQirrel expressions into XPath programs, XQuery queries or XSLT stylesheets.We provide some experimental results that compare our various evaluation strategies. We also show the runtime benefits of query composition over sequential evaluation.
Distributed caching of multi-dimensional data in mobile environments
Authors: Bin Liu, Wang-Chien Lee, Dik Lun Lee
Venue: Proceedings of the 6th international conference on Mobile data management (2005)

Caching has been an important technique for saving network traffic and reducing response time, especially in mobile environments where bandwidth is often a scarce resource. In this paper, we propose a novel approach for caching multidimensional data in a cluster of mobile devices. In particular, we focus on the most common types of multi-dimensional queries, namely range and k-nearest neighbor queries, by computing a cacheable region for every query, caching the result at the client, and indexing it in an R*-tree at the cluster gateway. Subsequent queries are first issued to the R*-tree and only remainder queries or queries that cannot be guaranteed exact answers are sent to the remote data server. To the best of our knowledge, our work is the first to study caching results from complex multi-dimensional queries (e.g., kNN query) and propose to build an R*-tree on previously fetched query results in a cluster of mobile devices. Rigorous experiments show that our approach significantly reduces network traffic and response time.
Pressure Correction Algebraic Splitting Methods for the Incompressible Navier-Stokes Equations
Authors: F. Saleri, A. Veneziani
Venue: SIAM Journal on Numerical Analysis (2005)

In this paper we present a new family of methods for the effective numerical solution of the incompressible unsteady Navier--Stokes equations. These methods resort to an algebraic splitting of the discretized problem based on inexact LU block factorizations of the corresponding matrix (following [A. Quarteroni, F. Saleri, and A. Veneziani, Comput. Methods Appl. Mech. Engrg., 188 (2000), pp. 505--526]. In particular, we will start from inexact algebraic factorizations of algebraic Chorin--Temam and Yosida type and introduce a pressure correction step aimed at improving the time accuracy. One of the schemes obtained in this way (the algebraic Chorin--Temam pressure correction method) resembles a method previously introduced in the framework of differential projection schemes (see [L. Timmermans, P. Minev, and F. V. de Vosse, Internat. J. Numer. Methods Fluids, 22 (1996), pp. 673--688], [A. Prohl, Projection and Quasi-Compressibility Methods for Solving the Incompressible Navier--Stokes Equations, Teubner, Stuttgart, 1997]. The stability and the dependence of splitting error on the time step of the new methods is investigated and tested on several numerical cases.