ppxscal/embedding_network huggingface dataset:
Views as first-class citizens in object-oriented databases
Authors: Reda Alhajj, Faruk Polat, Cem Y&#x00ed;lmaz
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (2005)

Extensibility and dynamic schema evolution are among the attractive features that lead to the wide acceptance of the object-oriented paradigm. Not knowing all class hierarchy details should not prevent a user from introducing new classes when necessary. Naive or professional users may define new classes either by using class definition constructs or as views. However, improper placement of such classes leads to a flat hierarchy with many things duplicated. To overcome this problem, we automated the process in order to help the user find the most appropriate position with respect to her class in the hierarchy regardless of her knowledge of the hierarchy. The system must be responsible for the proper placement of new classes because only the system has complete knowledge of the details of the class hierarchy, especially in a dynamic environment where changes are very frequent. In other published work, we proved that to define a view it is enough to have the set of objects that qualify to be in a view in addition to having message expressions (possible paths) that lead to desired values within those objects. Here, we go further to map a view that is intended to be persistent into a class. Then we investigate the proper position of that class in the hierarchy. To achieve this, we consider current characteristics of a new class in order to derive its relationship with other existing classes in the hierarchy. Another advantage of the presented model is that views that generate new objects are still updatable simply because we based the creation of new objects on existing identities. In other words, an object participates inside view objects by its identity regardless of which particular values from that object are of interest to the view. Values are reachable via message expressions, not violating encapsulation. This way, actual values are present in only one place and can be updated.
Cohen-Macaulay properties of square-free monomial ideals
Authors: Sara Faridi
Venue: Journal of Combinatorial Theory Series A (2005)

In this paper, we study simplicial complexes as higher-dimensional graphs in order to produce algebraic statements about their facet ideals. We introduce a large class of square-free monomial ideals with Cohen-Macaulay quotients, and a criterion for the Cohen-Macaulayness of facet ideals of simplicial trees. Along the way, we generalize several concepts from graph theory to simplicial complexes.
Creating Invariance to "Nuisance Parameters" in Face Recognition
Authors: Simon J. D. Prince, James H. Elder
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

A major goal for face recognition is to identify faces where the pose of the probe is different from the stored face. Typical feature vectors vary more with pose than with identity, leading to very poor recognition performance. We propose a non-linear many-to-one mapping from a conventional feature space to a new space constructed so that each individual has a unique feature vector regardless of pose. Training data is used to implicitly parameterize the position of the multi-dimensional face manifold by pose. We introduce a co-ordinate transform which depends on the position on the manifold. This transform is chosen so that different poses of the same face are mapped to the same feature vector. The same approach is applied to illumination changes. We investigate different methods for creating features which are invariant to both pose and illumination. We provide a metric to assess the discriminability of the resulting features. Our technique increases the discriminability of faces under unknown pose and lighting compared to contemporary methods.
The Effect of Stiffness and Curvature on the Haptic Identification of Surfaces
Authors: Vikram S. Chib, James L. Patton, Kevin M. Lynch, Ferdinando A. Mussa-Ivaldi
Venue: Proceedings of the First Joint Eurohaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2005)

We performed experiments to investigate how humans acquire an internal representation of virtual objects through the execution of reaching movements across the object surface. Subjects were instructed to make reaching movements between points lying on the boundary of a planar virtual surface of varying stiffness. Results suggest two types of internal representation: force perturbations and object boundaries. In the first case, a rectilinear hand movement is enforced by opposing the interaction forces. In the second case, the trajectory is conformed to the object boundary so as to reduce interaction forces. While this dichotomy is evident for very rigid and very soft objects, the likelihood of identifying a surface boundary depended, in a smooth and monotonic way, on the average force experienced in the first movements. This continuum of interactive behaviors suggests that the nervous system uses a weighted combination of two control strategies, one generating a compensatory response, the other a compliant motion.
The Perl debugger
Authors: Daniel Allen
Venue: Linux Journal (2005)

print("hello? Is this thing on?\n ");-or is there a better way?
Variance reduction in sample approximations of stochastic programs
Authors: Matti Koivu
Venue: Mathematical Programming: Series A and B (2005)

This paper studies the use of randomized Quasi-Monte Carlo methods (RQMC) in sample approximations of stochastic programs. In numerical integration, RQMC methods often substantially reduce the variance of sample approximations compared to Monte Carlo (MC). It seems thus natural to use RQMC methods in sample approximations of stochastic programs. It is shown, that RQMC methods produce epi-convergent approximations of the original problem. RQMC and MC methods are compared numerically in five different portfolio management models. In the tests, RQMC methods outperform MC sampling substantially reducing the sample variance and bias of optimal values in all the considered problems.
Rapid Development and Flexible Deployment of Adaptive Wireless Sensor Network Applications
Authors: Chien-Liang Fok, Gruia-Catalin Roman, Chenyang Lu
Venue: Proceedings of the 25th IEEE International Conference on Distributed Computing Systems (2005)

Wireless sensor networks (WSNs) are difficult to program and usually run statically-installed software limiting its flexibility. To address this, we developed Agilla, a new middleware that increases network flexibility while simplifying application development. An Agilla network is deployed with no pre-installed application. Instead, users inject mobile agents that spread across nodes performing application-specific tasks. Each agent is autonomous, allowing multiple applications to share a network. Programming is simplified by allowing programmers to create agents using a high-level language. Linda-like tuple spaces are used for inter-agent communication and context discovery. This preserves each agentýs autonomy while providing a rich infrastructure for building complex applications, and marks the first time mobile agents and tuple spaces are used in a unified framework for WSNs. Our efforts resulted in an implementation for MICA2 motes and the development of several applications. The implementation consumes a mere 41.6KB of code and 3.59KB of data memory. An agent can migrate 5 hops in less than 1.1 seconds with 92% reliability. In this paper, we present Agilla and provide a detailed evaluation of its implementation, an empirical study of its overhead, and a case study demonstrating its use.
Optimization of in-network data reduction
Authors: Joseph M. Hellerstein, Wei Wang
Venue: Proceeedings of the 1st international workshop on Data management for sensor networks: in conjunction with VLDB 2004 (2004)

We consider the in-network computation of approximate "big picture" summaries in bandwidth-constrained sensor networks. First we review early work on computing the Haar wavelet decomposition as a User-Defined Aggregate in a sensor query engine. We argue that this technique can be significantly improved by choosing a function-specific network topology. We generalize this discussion to a loose definition of a 2-level optimization problem that maps from a function to what we call a support graph for the function, and from there to an aggregation tree that is chosen from possible subgraphs of the physical network connectivity. This work is frankly quite preliminary: we raise a number of questions but provide relatively few answers. The intent of the paper is to lay groundwork for discussion and further research.
Reports and Surveys
Authors: Brian H. Rudall,  Prof.
Venue: Robotica (2005)

The importance of verifying safety-critical systems has been highlighted recently when the Embedded Systems Group (SEN2) and the Systems Validation Group (VASY) launched a collaboration agreement. Called SENVA, which represents System Engineering and Validation, this joint research team will add strength to this important area of endeavour. 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
Designing a Value Based Niche Search Engine Using Evolutionary Strategies
Authors: Sourav Sengupta, Bernard J. Jansen
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume I - Volume 01 (2005)

The advent of e-commerce and corporate intranets has led to the growth of organizational repositories containing large, fragmented, and unstructured document collections. Though it is difficult to retrieve relevant documents from such collections, it is relatively less cumbersome to define categories broadly classifying the information contained in the collection. Such categories lend value to the information contained in the collection. This research addresses the issue of improving retrieval accuracy of search engines that retrieve documents from organizational repositories using a value based approach. We test an evolutionary algorithm approach on a document collection. The precision of the search algorithm improved from 40% in generation 1 of the algorithm to nearly 90% in generation 10,000.
Knowledge Representation of Traditional Chinese Acupuncture Points Using the UMLS and a Terminology Model
Authors: Xinxin Zhu, KP Lee, James J. Cimino
Venue: Proceedings of the IDEAS Workshop on Medical Information Systems: The Digital Hospital (2004)

An escalating global interest in Traditional Chinese Acupuncture (TCA) demands easy use and reuse of the medical knowledge associated with TCA points, which in turn require appropriate knowledge representation of TCA. A proper knowledge representation generally involves enumeration of conceptual symbols and arrangement of these symbols into some meaningful structure. This study uses the Unified Medical Language System (UMLS) as the source of conceptual symbols and proposes a terminology model as the structure to arrange terms. The purpose is to systematically capture and represent appropriate TCA knowledge in practice. The initial terminology model is refined in an iterative process. The resulting terminology model captures and represents key aspects of TCA knowledge through properly designed model attributes and relations.
The Splitting Method as a Tool for Multiple Damage Analysis
Authors: Ivo Babuska, Börje Andersson
Venue: SIAM Journal on Scientific Computing (2005)

The paper presents a reliable and efficient method for solving problems on a large set of domains with different geometries. In applications these geometries might be idealizations of a mechanical structure with multiple damage. The method is designed, and used, to analyse large three-dimensional problems. The present paper formulates the method and presents the theory for a simple model problem, i.e., the Laplace equation in two dimensions. In the numerical implementation of the splitting scheme, the p-version of the finite element method and strongly graded meshes are used. This approach provides high accuracy and error control. The exponential rate of convergence of the method is shown and practically exemplified. A numerical example shows the effects of various choices of parameters on the accuracy of the method. A complex problem related to aircraft safety, which was solved using the present method, is used to exemplify the generality and the efficiency of the proposed method.
Assessing differential usage of usenet social accounting meta-data
Authors: A.J. Bernheim Brush, Xiaoqing Wang, Tammara Combs Turner, Marc A. Smith
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2005)

We describe a usage study of NetscanTech, a system that generates and publishes daily a range of social metrics across three dimensions: newsgroup, author, and thread, for a set of approximately 15,000 technical newsgroups in Usenet. We bring together three interlinked datasets: survey data, usage log data and social accounting data from Usenet participation, to triangulate the relationship between various user roles and differential usage of social metrics in NetscanTech. We found our most frequent users focused on information related to individual authors far more than any other information provided. In contrast, users that visited less frequently focused more on information related to newsgroups and viewing newsgroup metrics. Our results suggest features that designers and developers of online communities may wish to include in their interfaces to support the cultivation of different community roles.
Identifying Precursory Cancer Lesions Using Temporal Texture Analysis
Authors: Aldrin Barreto Flores, Leopoldo Altamirano Robles, Rosa Maria Morales Tepalt, Juan D. Cisneros Aragon
Venue: Proceedings of the 2nd Canadian conference on Computer and Robot Vision (2005)

This paper describes a method for the temporal analysis of texture in colposcopy. The objective is to find temporal texture patterns in order to detect precursory cancer lesions analyzing colposcopy video frames. Preprocessing of the frames is necessary in order to deal with patient movement and non uniform illumination. We use a stabilization algorithm based ina homography and to eliminate incorrect transformations between frames. Illumination correction is done using a local pixel transformation based in the mean around a small window. Temporal reaction after acetic acid application in the cervix is evaluated through the use of a co-occurrence matrix in different regions of the cervix. The reaction is plotted and analyzed through time. Different patterns for normal and abnormal regions are found by this temporal texture analysis showing the possibility to detect important lesions. The proposed method uses standard colposcopy equipment and it was tested using sequences obtained from different patients.
Strict Priority versus Weighted Fair Queueing in Switched Ethernet Networks for Time Critical Applications
Authors: Jean-Philippe Georges, Thierry Divoux, Eric Rondeau
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 2 - Volume 03 (2005)

In an industrial or technical context, some of the communications are strongly time-constrained. Our objective is to evaluate the service offered by a switched Ethernet architecture. We have chosen the network calculus theory because it gives a good representation of the exchanges and enables to determine the maximum end to end delays. Previous models implementing a strict priority policy presented in [A formal method to guarantee a deterministic behaviour of switched Ethernet networks for time-critical applications] are improved in order to take into account the Weighted Fair Queueing mechanism which enables to balance the allocation of the network to the different traffics regarding the time contraints they have to respect. This paper also presents the new analytical formulas which upper bound the maximum end-to-end delays of the time-critical messages over the whole network. This enables to determine the optimal bandwith dedicated to both critical and best effort traffics. On an industrial scenario, Strict Priority and Weighted Fair Queueing policies are finally compared.
Identifying link farm spam pages
Authors: Baoning Wu, Brian D. Davison
Venue: Special interest tracks and posters of the 14th international conference on World Wide Web (2005)

With the increasing importance of search in guiding today's web traffic, more and more effort has been spent to create search engine spam. Since link analysis is one of the most important factors in current commercial search engines' ranking systems, new kinds of spam aiming at links have appeared. Building link farms is one technique that can deteriorate link-based ranking algorithms. In this paper, we present algorithms for detecting these link farms automatically by first generating a seed set based on the common link set between incoming and outgoing links of Web pages and then expanding it. Links between identified pages are re-weighted, providing a modified web graph to use in ranking page importance. Experimental results show that we can identify most link farm spam pages and the final ranking results are improved for almost all tested queries.
Edge-Disjoint Isomorphic Multicolored Trees and Cycles in Complete Graphs
Authors: Gregory M. Constantine
Venue: SIAM Journal on Discrete Mathematics (2005)

It is shown that a complete graph with a prime number p,(>2) of vertices can be properly edge-colored with p colors in such a way that the edges can be partitioned into edge-disjoint multicolored Hamitonian cycles. When the number of vertices is $n\,(\geq 8)$, with n a power of two or five times a power of two, a proper edge-coloring of the complete graph exists such that its edges can be partitioned into isomorphic multicolored spanning trees. A subgraph is multicolored if each of its edges carries a different color.
Design, Implementation, and Evaluation of a Repairable Database Management System
Authors: Tzi-cker Chiueh, Dhruv Pilania
Venue: Proceedings of the 21st International Conference on Data Engineering (2005)

Although conventional database management systems are designed to tolerate hardware and to a lesser extent even software errors, they cannot protect themselves against syntactically correct and semantically damaging transactions, which could arise because of malicious attacks or honest mistakes. The lack of fast post-intrusion or post-error damage repair in modern DBMSs results in a longer Mean Time to Repair (MTTR) and sometimes permanent data loss that could have been saved by more intelligent repair mechanisms. In this paper, we describe the design and implementation of Phoenix - a system that significantly improves the efficiency and precision of a database damage repair process after an intrusion or operator error and thus, increases the overall database system availability. The two key ideas underlying Phoenix are (1) maintaining persistent inter-transaction dependency information at run time to allow selective undo of database transactions that are considered "infected" by the intrusion or error in question and (2) exploiting information present in standard database logs for fast selective undo. Performance measurements on a fully operational Phoenix prototype, which is based on the PostgreSQL DBMS, demonstrate that Phoenix incurs a response time and a throughput penalty of less than 5% and 8%, respectively, under the TPC-C benchmark, but it can speed up the post-intrusion database repair process by at least an order of magnitude when compared with a manual repair process.
An Ontology-enabled Service Oriented Architecture for Pervasive Computing
Authors: Qun Ni, Morris Sloman
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

In this paper, we propose a new Ontology-enabled Service Oriented Architecture (OSOA) for Pervasive Computing that is built on Web Services architecture, and incorporates Universal Plug and Play (UPnP). OSOA aims to combine context awareness and human-centric requirements related to ubiquitous computing with a new ontology-based approach to ad-hoc and goal-driven service composition.
Implementing aggregation and broadcast over Distributed Hash Tables
Authors: Ji Li, Karen Sollins, Dah-Yoh Lim
Venue: ACM SIGCOMM Computer Communication Review (2005)

Peer-to-peer (P2P) networks represent an effective way to share information, since there are no central points of failure or bottleneck. However, the flip side to the distributive nature of P2P networks is that it is not trivial to aggregate and broadcast global information efficiently. We believe that this aggregation/broadcast functionality is a fundamental service that should be layered over existing Distributed Hash Tables (DHTs), and in this work, we design a novel algorithm for this purpose. Specifically, we build an aggregation/broadcast tree in a bottom-up fashion by mapping nodes to their parents in the tree with a parent function. The particular parent function family we propose allows the efficient construction of multiple interior-node-disjoint trees, thus preventing single points of failure in tree structures. In this way, we provide DHTs with an ability to collect and disseminate information efficiently on a global scale. Simulation results demonstrate that our algorithm is efficient and robust.
Open-service-platform instrumentation: JMX management over OSGI
Authors: Stéphane Frénot, Dan Stefan
Venue: Proceedings of the 1st French-speaking conference on Mobility and ubiquity computing (2004)

Pervasive computing tries to narrow computer devices to the enduser in order to simplify access to his services. This trends currently visible in game online (Xbox live) or with the convergence between phone/internet/numeric television (freebox) is only made available by independent providers that works at defining closed platforms.Opening those &ldquo; service platforms &rdquo; leads to many problems when considering exploitation of those services by multiple providers. In this article, we will focus on instrumentation and supervision of those open service platforms by providing a standard instrumentation layer above them.
A study of clustering applied to multiple target tracking algorithm
Authors: Pavlina Konstantinova, Milen Nikolov, Tzvetan Semerdjiev
Venue: Proceedings of the 5th international conference on Computer systems and technologies (2004)

In this paper the effectiveness of two Data Association algorithms for Multiple Target Tracking (MTT) based on Global Nearest Neighbor approach are compared. As the time for assignment problem solution increases nonlinearly depending on the problem size, it is useful to divide the whole scenario on small groups of targets called clusters. For each cluster the assignment problem is solved by using-Munkres algorithm. Results reveal that the computational time especially for large scenarios decreases significantly when clustering is used.