ppxscal/embedding_network huggingface dataset:
Distributed, Uncertainty-Aware Access Control for Pervasive Computing
Authors: Urs Hengartner, Ge Zhong
Venue: Proceedings of the Fifth IEEE International Conference on Pervasive Computing and Communications Workshops (2007)

Access control to sensitive resources in pervasive computing needs to take uncertainty into account. Previous research has developed uncertainty-aware access-control models for environments that are managed by a centralized administrator. We demonstrate that environments managed in a distributed way require a more powerful model. Furthermore, we point out additional challenges that need to be considered when deploying uncertainty-aware access control, namely, identifying and authenticating both people and their intended actions, associating uncertainty with time, providing monotonicity, and defending against Sybil attacks. We present an access-control model that addresses these challenges and discuss a sample implementation.
A New Approach for Accelerating the Sparse Matrix-Vector Multiplication
Authors: Pavel Tvrdik, Ivan Simecek
Venue: Proceedings of the Eighth International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (2006)

Sparse matrix-vector multiplication (shortly SpM×V ) is one of most common subroutines in the numerical linear algebra. The problem is that the memory access patterns during the SpM×V are irregular and the utilization of cache can suffer from low spatial or temporal locality. This paper introduces new approach for the acceleration the SpM×V . This approach consists of 3 steps. The first step divides the whole matrix into smaller parts (regions) those can fit in the cache. The second step improves locality during the multiplication due to better utilization of distant references. The last step maximizes machine computation performance of the partial multiplication for each region. In this paper, we describe aspects of these 3 steps in more detail (including fast and time-inexpensive algorithms for all steps). Our measurements proved that our approach gives a significant speedup for almost all matrices arising from various technical areas.
Cha-Cha: a system for organizing intranet search results
Authors: Michael Chen, Marti Hearsty, Jason Hong, James Lin
Venue: Proceedings of the 2nd conference on USENIX Symposium on Internet Technologies and Systems - Volume 2 (1999)

Although search over World Wide Web pages has recently received much academic and commercial attention, surprisingly little research has been done on how to search the web pages within large, diverse intranets. Intranets contain the information associated with the internal workings of an organization. A standard search engine retrieves web pages that fall within a widely diverse range of information contexts, but presents these results uniformly, in a ranked list. As an alternative, the Cha-Cha system organizes web search results in such a way as to reflect the underlying structure of the intranet. In our approach, an "outline" or "table of contents" is created by first recording the shortest paths in hyperlinks from root pages to every page within the web intranet. After the user issues a query, these shortest paths are dynamically combined to form a hierarchical outline of the context in which the search results occur. The system is designed to be helpful for users with a wide range of computer skills. Preliminary user study and survey results suggest that some users find the resulting structure more helpful than the standard retrieval results display for intranet search.
Privacy-aware role based access control
Authors: Qun Ni, Alberto Trombetta, Elisa Bertino, Jorge Lobo
Venue: Proceedings of the 12th ACM symposium on Access control models and technologies (2007)

Privacy has been acknowledged to be a critical requirement for many business (and non-business) environments. Therefore, the definition of an expressive and easy-to-use privacy related access control model, based on which privacy policies can be specified, is crucial. In this work we introduce a family of models (P-RBAC) that extend the well known RBAC model in order to provide full support for expressing highly complex privacy-related policies, taking into account features like purposes and obligations. We also compare our work with access control and privacy policy frameworks such as P3P, EPAL, and XACML.
Fixing races for fun and profit: how to use access(2)
Authors: Drew Dean, Alan J. Hu
Venue: Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 (2004)

It is well known that it is insecure to use the access(2) system call in a setuid program to test for the ability of the program's executor to access a file before opening said file. Although the access(2) call appears to have been designed exactly for this use, such use is vulnerable to a race condition. This race condition is a classic example of a time-of-check-to-time-of-use (TOCTTOU) problem. We prove the "folk theorem" that no portable, deterministic solution exists without changes to the system call interface, we present a probabilistic solution, and we examine the effect of increasing CPU speeds on the exploitability of the attack.
Time-frequency methods for analyzing structural response data
Authors: P. R. White
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 06 (2000)

This paper considers the application of various time-frequency methods to structural response data. It illustrates that by use of time-frequency methods information that is not evident in impulse or frequency responses data is brought to light. The shortcomings of classical bilinear time-frequency representations are discussed. A selection of data adaptive time-frequency methods designed as enhancements to the classical techniques are compared and contrasted for this application. It is shown that many of these algorithms fail to give acceptable results when applied to the comparatively complex data sets considered here.
Using multimedia courseware in engineering education
Authors: A. Azemi
Venue: Proceedings of the 26th Annual Frontiers in Education - Volume 01 (1996)

The paper presents the use of multimedia tools in teaching engineering courses. In particular we discuss the use of "courseware" in conducting classroom teaching for the first electrical engineering circuits course. Some of the questions and/or concerns that have been raised regarding the use of a courseware package and advantages and disadvantages of using such an approach including the developer's comments and students' reactions are included. A brief summary of the steps required to produce courseware is also provided. The results presented are based on an ongoing project that has been partially funded by the Pennsylvania State University and Lenohard Engineering Center of Excellence. The courseware modules are a series of executable files that can be used in a Windows environment. They also provide links to other useful software packages such as PSPICE and MATLAB. Various examples utilizing these programs are included in the package. A working courseware example is also presented.
POCS-based blind array processing in incoherent microwave radiometric image reconstruction
Authors: K. Teramoto
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 05 (1996)

A microwave scanning radiometer is the powerful equipment for obtaining precise data of microwave-radiation however the spatial resolution is larger than many of the objects of interest within the image. If the exact antenna directional pattern and the orbit of the satellite can be known, the image reconstruction can be done exactly. Actually, it is difficult to know the antenna directional pattern or the point spread function (PSF) of the imaging system exactly because the directional pattern of the antenna is changed in space due to thermal stress, mechanical stress or vibrations. Under such a condition, the image reconstruction process is much more sensitive to the PSF changes and additive noise. It is necessary to reduce the instability that is called the 'ill-posed problem in inverse problem'. Therefore, a new blind array processing algorithm based on a conjugate gradient-projection onto convex sets (CG-POCS) for signal recovery and image reconstruction in an incoherent signal is proposed. Its advantages are shown by numerical experiments based on the parametric data of the Advanced Microwave Scanning Radiometer (AMSR) of the Advanced Earth Observing Satellite-II (ADEOS-II).
Stages in Teaching Software Design
Authors: A. J. Cowling
Venue: Proceedings of the 20th Conference on Software Engineering Education & Training (2007)

This paper describes how a staged approach to the development of students' abilities to engineer software systems applies to the specific issue of teaching software design. It evaluates the courses relating to software design in the Software Engineering volume of Computing Curriculum 2001 with a theoretical model that has been developed from a well-established programme in software engineering, from the perspectives of how well the courses support the progressive development of both students' knowledge of software design and their ability to design software systems. This evaluation identifies some topics that would be better taught earlier than recommended, and others that should be deferred until later in the curriculum.
Cascaded Data Mining Methods for Text Understanding, with medical case study
Authors: Roni Romano, Lior Rokach, Oded Maimon
Venue: Proceedings of the Sixth IEEE International Conference on Data Mining - Workshops (2006)

Substantial electronically stored textual data such as clinical narratives reports often need to be retrieved to find relevant information for clinical and research purposes. The context of negation, a negative finding, is of special importance, since many of the most frequently described findings are such. Hence, when searching free-text narratives for patients with a certain medical condition, if negation is not taken into account, many of the documents retrieved will be irrelevant. We present a new cascaded pattern learning method for automatic identification of negative context in clinical narratives re-ports. Studying the training corpuses, the classification errors and patterns selected by the classifier, we noticed that it is possible to create a more powerful ensemble structure than the structure obtained from general-purpose ensemble method (such as Adaboost). We compare the new algorithm to previous methods proposed for the same task of similar medical narratives, and show its advantages: accuracy improvement compared to other machine learning methods, and much faster than manual knowledge engineering techniques with matching accuracy.
Adaptive SSL: Design, Implementation and Overhead Analysis
Authors: C. J. Lamprecht, Aad P. A. van Moorsel
Venue: Proceedings of the First International Conference on Self-Adaptive and Self-Organizing Systems (2007)

Adaptive security is based on the observation that the se- curity requirements of a system or service heavily depend on the environment in which they operate and should therefore be dynamically adjusted to best operate within that envi- ronment as the environment changes. In this paper we are concerned with adapting the choice of cryptographic algo- rithms applied to client-server interactions. To that end, we design and implement an adaptation controller for SSL (Se- cure Socket Layer), called Adaptive SSL.
Multifaceted Hyperimage-Based Organization and Interaction with Bio-Medical Images
Authors: Rahul Singh, Pierre-Yves Corlobe
Venue: Proceedings of the Twentieth IEEE International Symposium on Computer-Based Medical Systems (2007)

abundance of complex media-rich information in state-of-the-art bio-medical sciences underlines the importance of paradigms for organizing, searching, browsing, and assimilating such data. In this context, image-based information, derived from a plethora of biological and medical devices, presents unique challenges. This is partially due to the richness of information expressible through visual media and the complexity of the underlying semantics. There is today a paucity of paradigms that allow organization and browsing of large image collections, in manners that capture the intricacies of image semantics and support experiential factors in information assimilation and user-data interactions. This paper presents our research in designing such an organizational framework. Central to our approach is the philosophy of recognizing and directly capturing the heterogeneity of semantics that may exist even for a single bio-medical image. Using this as a starting point, we extend the notion of image hyperlinking to support multiple semantic associations between bio-medical images. By using these associations, expressed as hyperlinks, image collections can be organized simultaneously from different biological or medical perspectives. We also consider the issues of creating, storing, and managing information in such an organizational paradigm. Finally, we describe a unified presentation-interaction environment that facilitates user interactions including information organization, querying, and exploration. Examples and case studies demonstrate the promise and broad applicability of this research.
Membrane Systems with Peripheral Proteins: Transport and Evolution
Authors: Matteo Cavaliere, Sean Sedwards
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2007)

Transport of substances and communication between compartments are fundamental biological processes, often mediated by the presence of complementary proteins attached to the surfaces of membranes. Within compartments, substances are acted upon by local biochemical rules. Inspired by this behaviour we present a model based on membrane systems, with objects attached to the sides of the membranes and floating objects that can move between the regions of the system. Moreover, in each region there are evolution rules that rewrite the transported objects, mimicking chemical reactions. We first analyse the system, showing that interesting qualitative properties can be decided (like reachability of configurations) and then present a simulator based on a stochastic version of the introduced model and show how it can be used to simulate relevant quantitative biological processes.
Two-dimensional phase retrieval using a window function
Authors: Wooshik Kim
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 03 (1999)

This paper considers two-dimensional phase retrieval using a window function. First, we address the uniqueness and reconstruction of a two-dimensional signal from the Fourier intensities of the three signals: the original signal, the signal windowed by a window w(m,n) and the signal windowed by its complementary window w/sub c/(m,n)=1-w(m,n). Then we consider the phase retrieval without a complementary window. We develop conditions under which a signal can be uniquely specified from the Fourier intensities of the original signal and the windowed signal by w(m,n). We also present a reconstruction algorithm. 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
A class of logarithmically completely monotonic functions and the best bounds in the first Kershaw's double inequality
Authors: Feng Qi
Venue: Journal of Computational and Applied Mathematics (2007)

In the article, the logarithmically complete monotonicity of a class of functions involving Euler's gamma function are proved, a class of the first Kershaw-type double inequalities are established, and the first Kershaw's double inequality and Wendel's inequality are generalized, refined or extended. Moreover, an open problem is posed.
Image segmentation by clustering of spatial patterns
Authors: Yong Xia, (David) Dagan Feng, Tianjiao Wang, Rongchun Zhao, Yanning Zhang
Venue: Pattern Recognition Letters (2007)

This letter describes an approach to perceptual segmentation of images through the means of clustering of spatial patterns. An image is modeled as a set of spatial patterns defined on a rectangular lattice. The distance between a spatial pattern and each cluster is defined as a combination of the Euclidean distance in the feature space and the spatial dissimilarity which reflects how much of the pattern's neighbourhood is occupied by other clusters. Our approach has been compared with the Fuzzy C-Mean (FCM) algorithm, a spatial fuzzy clustering algorithm and a Markov Random Field (MRF) based algorithm by segmenting synthetic images, texture mosaics and natural images. The results of those comparative experiments demonstrate that the proposed approach can segment images more effectively and provide more robust segmentation results.
An Account of Implementing Applicative Term Rewriting
Authors: Muck van Weerdenburg
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2007)

Generation of labelled transition systems from system specifications is highly dependent on efficient rewriting (or related techniques). We give an account of the implementation of two rewriters of the mCRL2 toolset. These rewriters work on open terms and use nonlinear match trees. A comparison is made with other commonly used efficient rewriters.
The Procedure Model and Implementation Technology of VE for Science Education
Authors: Ruwei Yun, Huimin Shi, Yi Li, Zhigeng Pan
Venue: Proceedings of the The First IEEE International Workshop on Digital Game and Intelligent Toy Enhanced Learning (2007)

Experiment is important for science education. Sometime it is hard to do real experiment because of the limitation of time, space and expense etc.. Virtual experiment system is a computer-based 3D virtual environment which allows users to explore as in a real world and carry out experiments effectively. As supplements to real experiments, virtual experiments have attracted great interests of experts in science education. This paper introduces the procedure model and hierarchical analysis of designing a virtual experiment system. Some key implementation technologies are also introduced.
Tailoring quantum architectures to implementation style: a quantum computer for mobile and persistent qubits
Authors: Eric Chi, Stephen A. Lyon, Margaret Martonosi
Venue: Proceedings of the 34th annual international symposium on Computer architecture (2007)

In recent years, quantum computing (QC) research has moved from the realm of theoretical physics and mathematics into real implementations. With many different potential hardware implementations, quantum computer architecture is a rich field with an opportunity to solve interesting new problems and to revisit old ones. This paper presents a QC architecture tailored to physical implementations with highly mobile and persistent quantum bits (qubits). Implementations with qubit coherency times that are much longer than operation times and qubit transportation times that are orders of magnitude faster than operation times lend greater flexibility to the architecture. This is particularly true in the placement and locality of individual qubits. For concreteness, we assume a physical device model based on electron-spin qubits on liquid helium (eSHe). Like many conventional computer architectures, QCs focus on the efficient exposure of parallelism.We present here a QC microarchitecture that enjoys increasing computational parallelism with size and latency scaling only linearly with the number of operations. Although an efficient and high level of parallelism is admirable, quantum hardware is still expensive and difficult to build, so we demonstrate how the software may be optimized to reduce an application's hardware requirements by 25% with no performance loss. Because the majority of a QC's time and resources are devoted to quantum error correction, we also present noise modeling results that evaluate error correction procedures. These results demonstrate that idle qubits in memory need only be refreshedapproximately once every one hundred operation cycles.
A Review of an Optimal Design Problem for a Plate of Variable Thickness
Authors: Julio Mun&tilde;oz, Pablo Pedregal
Venue: SIAM Journal on Control and Optimization (2007)

We revisit a classic design problem for a plate of variable thickness under the model of Kirchhoff. Our main contribution has two goals. One is to provide a rather general existence result under a main assumption on the structure of the tensor of material constants. The other focuses on providing a minimal number of additional design variables for a relaxation of the problem when that assumption on the tensor of elastic constants does not hold. In both situations, the cost functional can be pretty general.
Department of Redundancy Department?
Authors: James Hendler
Venue: IEEE Intelligent Systems (2007)

This issue features a new department: Applications: Homeland Security. Picking the name was no easy matter.
A system for semantic data fusion in sensor networks
Authors: Alex Wun, Milenko Petrovi, Hans-Arno Jacobsen
Venue: Proceedings of the 2007 inaugural international conference on Distributed event-based systems (2007)

Emerging sensor network technologies are expected to substantially augment applications such as environmental monitoring, health-care, and home/commercial automation. However, much of the existing work focuses mainly on collecting and using sensor level data from isolated sensor networks directly, which still burdens applications with the task of interpreting the context and meaning of sensor data. In order to infer high-level phenomena, sensor data needs to be filtered, aggregated, correlated, and translated from many heterogeneous and dispersed sensor networks. In this paper, we present a novel system for decoupling the process of semantic data fusion from application logic based on semantic Content-based Publish/Subscribe techniques. Our main contribution is an integrated system that allows efficient semantic event detection to occur both within and across sensor networks by translating events using ontologies.
An improved variable-size block-matching algorithm
Authors: Haifeng Wang, Qingshan Liu, Hanqing Lu
Venue: Multimedia Tools and Applications (2007)

In this paper, we proposed an improved "bottom---up" variable-size block matching method. Different from previous work, the proposed method does not need any threshold during the matching, and we just keep all the motion vectors leading to the minimum matching error. A Marco-block mode prediction method is put forward to speed up the motion estimation procedure without introducing any loss to the prediction precision. The improved variable-size block matching algorithm can achieve exactly the same prediction precision as full-search based fixed-size block matching algorithm. In order to reduce the effect of illumination change on mode selection, we proposed an illumination removal method, which acts as a post-processing step to prevent the macro-blocks from over-splitting. Experiments show its encouraging performance.