ppxscal/embedding_network huggingface dataset:
Online signature verification using a new extreme points warping technique
Authors: Hao Feng, Chan Choong Wah
Venue: Pattern Recognition Letters (2003)

There are two common methodologies to verify signatures: the functional approach and the parametric approach. In this paper, we propose a new warping technique for the functional approach in signature verification. The commonly used warping technique is dynamic time warping (DTW). It was originally used in speech recognition and has been applied in the field of signature verification with some success since two decades ago. The new warping technique we propose is named as extreme points warping (EPW). It proves to be more adaptive in the field of signature verification than DTW, given the presence of the forgeries. Instead of warping the whole signal as DTW does, EPW warps a set of selected important points. With the use of EPW, the equal error rate is improved by a factor of 1.3 and the computation time is reduced by a factor of 11.
Network capacity allocation for traffic with time priorities
Authors: Xian Liu
Venue: International Journal of Network Management (2003)

The packet switching techniques are undergoing evolution. The conventional 'best effort' approach will no longer be the dominant service. The next generation of IP networks must provide QoS to customers. Inadequacy is obvious when the conventional capacity allocation (CA) models are applied to the new IP architecture. In this paper, we propose several CA models that characterize: (1) the service priority scheme; (2) the service preemption scheme; and (3) the non-Poisson traffic in which the packets follow heavy tailed distributions.
Space-Time Receiver for Multi-Rate CDMA Systems: Multi-Code and VariableSpreading Length Access Methods Comparison
Authors: Jinwen Ma, Hongya Ge
Venue: Wireless Personal Communications: An International Journal (2003)

This work proposed the linear minimum mean square error (LMMSE) space-time receivers for synchronous multi-rate direct sequence code devision multiple access (DS/CDMA) systems. The performance of the proposed receivers is analyzed. The high-rate (HR) LMMSE space-time receiver with combining technique can provide essentially the same performance for low-rate (LR) users as LR LMMSE space-time receiver while eliminate the time delay for the HR users. The performance of the proposed multi-rate LMMSE space-time receivers are studied in the context of two multi-rate access methods: multi-code (MC) access where high data rate users multiplex their information streams onto multiple codes, and variable spreading length (VSL) access where signature sequences of different lengths are assigned to users with different data rates. Through the simulation results, we show that: (a) the proposed multi-rate LMMSE space-time receivers are optimum near-far resistant; (b) the proposed multi-rate LMMSE space-time receivers have a clear performance improvement compared to the time only LMMSE dual rate receiver; (c) there is a performance gain of the proposed multi-rate LMMSE space-time receivers compared to the multi-rate decorrelating space-time receiver when near-far ratio (NFR) is low; (d) The performance difference between MMSE combining and MRC in multi-rate system is much more pronounced than in single-rate system. Simulations also show that the VSL access method is more robust than MC access method considering changing rate-ratio in multi-rate systems.
Coping with ambiguity and unknown words through probabilistic models
Authors: Ralph Weischedel, Richard Schwartz, Jeff Palmucci, Marie Meteer, Lance Ramshaw
Venue: Computational Linguistics (1993)

From spring 1990 through fall 1991, we performed a battery of small experiments to test the effectiveness of supplementing knowledge-based techniques with probabilistic models. This paper reports our experiments in predicting parts of speech of highly ambiguous words, predicting the intended interpretation of an utterance when more than one interpretation satisfies all known syntactic and semantic constraints, and learning caseframe informationfor verbsfrom example uses.From these experiments, we are convinced that probabilistic models based on annotated corpora can effectively reduce the ambiguity in processing text and can be used to acquire lexical informationfrom a corpus, by supplementing knowledge-based techniques.Based on the results of those experiments, we have constructed a new natural language system (PLUM) for extracting data from text, e.g., newswire text.
Cooperation strategies for agent-based P2P systems
Authors: Loris Penserini, Lin Liu, John Mylopoulos, Maurizio Panti, Luca Spalazzi
Venue: Web Intelligence and Agent Systems (2003)

We are interested in peer-to-peer (P2P) computing, where a P2P application consists of a (wireless) network of nodes (peers), and assumes full peer autonomy, no global control, and intermittent connectivity. P2P computing has many advantages over classical client-server and web-based distributed architectures. However, the P2P computing model also has a number of limitations in the mechanisms it supports for data management and interchange. To overcome some of these, we propose an agent-based P2P model whose nodes are software agents (peer agents). This paper uses the i* modeling framework to analyze and evaluate peer agent cooperation strategies using three possible evaluation criteria.
Modal operators and the formal dual of Birkhoff's completeness theorem
Authors: Steve Awodey, Jesse Hughes
Venue: Mathematical Structures in Computer Science (2003)

We present the dual to Birkhoff's variety theorem in terms of predicates over the carrier of a cofree coalgebra (that is, in terms of &lsquo;coequations&rsquo;). We then discuss the dual to Birkhoff's completeness theorem, showing how closure under deductive rules dualises to yield two modal operators acting on coequations. We discuss the properties of these operators and show that they commute. We prove as our main result the invariance theorem, which is the formal dual of Birkhoff's completeness theorem.
Conceptualising tangibles to support learning
Authors: Paul Marshall, Sara Price, Yvonne Rogers
Venue: Proceedings of the 2003 conference on Interaction design and children (2003)

We present a new way of conceptualising tangibles for learning. This scheme adopts Heidegger's analysis of the ways a user can treat a tool: either as 'ready-to-hand' or 'present-at-hand'. It also proposes two types of activity a learner can engage in when using a tangible: either exploratory or expressive activity. Finally, two types of models that a user can explore are proposed: theoretical and practical models.Examples from the literature are described in terms of this framework and an example is given from our own work of an attempt to use this conceptualisation in design.
Building and evaluating an intelligent pedagogical agent to improve the effectiveness of an educational game
Authors: Cristina Conati, Xiaohong Zhao
Venue: Proceedings of the 9th international conference on Intelligent user interfaces (2004)

Electronic educational games can be highly entertaining, but studies have shown that they do not always trigger learning. To enhance the effectiveness of educational games, we propose intelligent pedagogical agents that can provide individualized instruction integrated with the entertaining nature of the games. In this paper, we describe one such agent, that we have developed for Prime Climb, an educational game on number factorization. The Prime Climb agent relies on a probabilistic student model to generate tailored interventions aimed at helping students learn number factorization through the game. After describing the functioning of the agent and the underlying student model, we report the results of an empirical study that we performed to test the agent's effectiveness.
An overview of positioning by diffusion
Authors: Michael Spratt
Venue: Wireless Networks (2003)

Positioning by Diffusion is a method by which mobile and static devices can calculate their positions, by means of exchanging information over short range wireless links. It is intended for deployment within shopping malls, corporate buildings, theme parks, etc. The implementation is in software, and does not impose extra hardware requirements on mobile or static devices. Another objective is to minimize the system administration and deployment costs, by minimizing the required number of devices which have their position programmed into them - devices we define as Access Points - for the system to operate. The positioning system works instead by a seamless inter-working of the algorithm across Access Points, static devices which learn their position rather than having it pre-programmed, and mobile devices. Positioning by Diffusion is being adopted by the Bluetooth Local Positioning Working Group as its positioning algorithm.
Metadata-Driven Middleware for Web Services
Authors: Francisco Curbera, Nirmal Mukhi
Venue: Proceedings of the Fourth International Conference on Web Information Systems Engineering (2003)

Service metadata plays a central role in Service Oriented Architecture (SOA)s. Explicit service metadata makes possible the decoupling of applications and supports dynamic selection and binding. Moreover it extends the basic interoperability model beyond the implicit agreement to use a set of common protocols, making possible advanced collaboration models based on the dynamic discovery of partner capabilities. Web services provide the beginning of an XML based instantiation of the SOA model, with major middleware vendors providing implementations on top of their current platforms. In this paper, we discuss how the use ofmiddleware metadata in SOA environments leads to optimized interaction and increase application decoupling.
Indexing of network constrained moving objects
Authors: Dieter Pfoser, Christian S. Jensen
Venue: Proceedings of the 11th ACM international symposium on Advances in geographic information systems (2003)

With the proliferation of mobile computing, the ability to index efficiently the movements of mobile objects becomes important. Objects are typically seen as moving in two-dimensional (x,y) space, which means that their movements across time may be embedded in the three-dimensional (x,y,t) space. Further, the movements are typically represented as trajectories, sequences of connected line segments. In certain cases, movement is restricted, and specifically in this paper, we aim at exploiting that movements occur in transportation networks to reduce the dimensionality of the data. Briefly, the idea is to reduce movements to occur in one spatial dimension. As a consequence, the movement data becomes two-dimensional (x,t). The advantages of considering such lower-dimensional trajectories are the reduced overall size of the data and the lower-dimensional indexing challenge. Since off-the-shelf systems typically do not offer higher-dimensional indexing, this reduction in dimensionality allows us to use such DBMSes to store and index trajectories. Moreover, we argue that, given the right circumstances, indexing these dimensionality-reduced trajectories can be more efficient than using a three-dimensional index. This hypothesis is verified by an experimental study that incorporates trajectories stemming from real and synthetic road networks.
Imaging technologies in JAVA
Authors: Anupama Akre, Sabin Tabirca
Venue: Proceedings of the 2nd international conference on Principles and practice of programming in Java (2003)

Digital imaging in Java has been supported since its first release, through the java.awt and java.awt.image class packages. Now there are three distinct java imaging APIs namely, the basic AWT imaging API, Java 2D API and Java Advance Imaging (JAI) API. This paper firstly summarizes and compares important features of AWT, Java2D and JAI APIs. Then the Java2D and JAI technologies are compared based on practical results obtained by evaluation of convolution.
New key management protocol for SSL/TLS
Authors: Ibrahim Hajjeh, Ahmed Serhrouchni, Frédérique Tastet
Venue: Network control and engineering for Qos, security and mobility II (2003)

In 1998, the IETF adopted ISAKMP (Internet Security association and key management protocol) as the standard key management protocol for IPSEC. ISAKMP was conceived to be a generic protocol, its features and capabilities were intended to provide a standard framework for the negotiation of security parameters for any security protocol. However, since then, ISAKMP has never been used outside the IPSEC framework. In this paper, we give a new dimension for ISAKMP by establishing a secure session for the SSL/TLS protocol. The main objective of this integration is to exploit the unused functionalities of ISAKMP and extend the work of SSL/TLS to support new services. We also analysé and discuss the recent successors to the ISAKMP protocol.
Exposing resource tradeoffs in region-based communication abstractions for sensor networks
Authors: Matt Welsh
Venue: ACM SIGCOMM Computer Communication Review (2004)

We argue that communication abstractions for wireless sensor networks should expose the tradeoff between accuracy and resource usage, allowing applications to adapt to changing network conditions and tune energy and bandwidth requirements. We describe abstract regions, a family of spatial operators that capture local communication with regions of the network, which may be defined in terms of radio connectivity, geographic location, or other properties of nodes. Abstract regions provide feedback on the quality of collective operations, and expose an interface for tuning resource consumption. We present the implementation of abstract regions in the TinyOS programming environment, as well as preliminary results demonstrating their use of building adaptive sensor network applications.
An adaptive energy-efficient MAC protocol for wireless sensor networks
Authors: Tijs van Dam, Koen Langendoen
Venue: Proceedings of the 1st international conference on Embedded networked sensor systems (2003)

In this paper we describe T-MAC, a contention-based Medium Access Control protocol for wireless sensor networks. Applications for these networks have some characteristics (low message rate, insensitivity to latency) that can be exploited to reduce energy consumption by introducing an activesleep duty cycle. To handle load variations in time and location T-MAC introduces an adaptive duty cycle in a novel way: by dynamically ending the active part of it. This reduces the amount of energy wasted on idle listening, in which nodes wait for potentially incoming messages, while still maintaining a reasonable throughput.We discuss the design of T-MAC, and provide a head-to-head comparison with classic CSMA (no duty cycle) and S-MAC (fixed duty cycle) through extensive simulations. Under homogeneous load, T-MAC and S-MAC achieve similar reductions in energy consumption (up to 98%) compared to CSMA. In a sample scenario with variable load, however, T-MAC outperforms S-MAC by a factor of 5. Preliminary energy-consumption measurements provide insight into the internal workings of the T-MAC protocol.
Measuring the potential for IT convergence at macrolevel: a definition based on platform penetration and CRM potential
Authors: Margherita Pagani
Venue: Technologies & methodologies for evaluating information technology in business (2003)

In this chapter, the author sets out to define what convergence is and to measure it in Europe. It begins by proposing that the concept of digital convergence, as it is commonly expressed, is taken to refer to three possible axes of alignment: convergence of devices, convergence of networks, and convergence of content. Although there is evidence in digital environments of limited alignment in some of these areas, there are considerable physical, technical, and consumer barriers in each case. In fact, rather than convergence, the transition from analog to digital is often accompanied by a process of fragmentation. A better way of looking at convergence may lie in the degree to which two-way digital networks facilitate cross-platform management of customer relationships, regardless of the type of networks those customers use. In the chapter, a definition of convergence based on penetration of digital platforms and the potential for cross-platform Customer Relationship Management (CRM) strategies is argued for before going on to develop a convergence index according to different European territories that can be compared.
A Color Vision-Based Lane Tracking System for Autonomous Driving on Unmarked Roads
Authors: Miguel Angel Sotelo, Francisco Javier Rodriguez, Luis Magdalena, Luis Miguel Bergasa, Luciano Boquete
Venue: Autonomous Robots (2004)

This work describes a color Vision-based System intended to perform stable autonomous driving on unmarked roads. Accordingly, this implies the development of an accurate road surface detection system that ensures vehicle stability. Although this topic has already been documented in the technical literature by different research groups, the vast majority of the already existing Intelligent Transportation Systems are devoted to assisted driving of vehicles on marked extra urban roads and highways. The complete system was tested on the BABIECA prototype vehicle, which was autonomously driven for hundred of kilometers accomplishing different navigation missions on a private circuit that emulates an urban quarter. During the tests, the navigation system demonstrated its robustness with regard to shadows, road texture, and weather and changing illumination conditions.
Ontology modeling tool with concept dictionary
Authors: Yoichi Hiramatsu, Seiji Koide
Venue: Proceedings of the 9th international conference on Intelligent user interfaces (2004)

The usefulness of ontology is strongly dependent on the knowledge representation policy and its maintenance. The subject of knowledge representation and modeling tool has been one of the exciting themes among ontology scientists. Some ontology editing tools were born and grew up in the field of expert system and others designed originally by ontology research groups. Key features of the newly implemented tool are: reference to the concept dictionary to find out semantics of the words, and use of inference algorithm provided by Schank's Memory Organization Package. Satisfactory results were obtained in the application of ontology modeled by the present tool. This paper describes the implementation of the tool and its effectiveness in solving some actual problems of enterprise integration.
Zeros of Reliability Polynomials and f-vectors of Matroids
Authors: David G. Wagner
Venue: Combinatorics, Probability and Computing (2000)

For a finite multigraph G, the reliability function of G is the probability RG(q) that if each edge of G is deleted independently with probability q then the remaining edges of G induce a connected spanning subgraph of G; this is a polynomial function of q. In 1992, Brown and Colbourn conjectured that, for any connected multigraph G, if q &isin; &Copf; is such that RG(q) = 0 then &#x2223;q&#x2223; &le; 1. We verify that this conjectured property of RG(q) holds if G is a series-parallel network. The proof is by an application of the Hermite&ndash;Biehler theorem and development of a theory of higher-order interlacing for polynomials with only real nonpositive zeros. We conclude by establishing some new inequalities which are satisfied by the f-vector of any matroid without coloops, and by discussing some stronger inequalities which would follow (in the cographic case) from the Brown&ndash;Colbourn conjecture, and are hence true for cographic matroids of series-parallel networks.
Models of Infection: Person to Person
Authors: Dianne P. O'Leary
Venue: Computing in Science and Engineering (2004)

When faced with a spreading infection, public health workers want to predict its path and severity to make decisions about vaccination strategies, quarantine policy, and the use of public health resources. This is true whether the pathogen's dispersion is natural (for example, the spread of influenza in 1918) or deliberate (for example, the spread of anthrax via terrorism). Effective mathematical models can help us test a public health policy's potential outcome and arrive at an effective response. In this issue, we focus on a simplified model of the spread of an infection and develop some tools that lend insight into its behavior.
Design and Implementation of a Cache-Conscious Index Manager for the Tachyon, a Main Memory DBMS
Authors: Kyung-Tae Lee, Inbum Jung, Chang-Yeol Choi, Wan Choi, Sang-Wook Kim
Venue: Proceedings of the 27th Annual International Conference on Computer Software and Applications (2003)

The main memory DBMS(MMDBMS) efficientlysupports various database applications that require high performance since it employs main memoryrather than disk as a primary storage. In thispaper, we discuss the cache-conscious index manager of the Tachyon, a next generationMMDBMS. The index manager is an essentialsub-component of a DBMS used to speed up the retrieval of objects from a large volume of adatabase in response to a certain search condition.Recently, the gap between the CPU processing and main memory access times is becoming much widerdue to rapid advance of CPU technology. Bydevising data structures and algorithms that utilize the behavior of the cache in CPU, we are able toenhance the overall performance of MMDBMSsconsiderably. In this paper, we address the practical implementation issues and our solutionsfor them obtained in developing the cache-consciousindex manager of the Tachyon. The main issues touched are (1) consideration of the cachebehavior, (2) compact representation of an indexentry, (3) support of variable-length keys, (4) support of multiple-attribute keys, (5) support ofduplicated keys, and (6) definition of the systemcatalog for indexes. We also show the effectiveness of our approach through extensiveexperiments.
Automated index management for distributed web search
Authors: Rinat Khoussainov, Nicholas Kushmerick
Venue: Proceedings of the twelfth international conference on Information and knowledge management (2003)

Distributed heterogeneous search systems are an emerging phenomenon in Web search, in which independent topic-specific search engines provide search services, and metasearchers distribute user's queries to only the most suitable search engines. Previous research has investigated methods for engine selection and merging of search results (i.e. performance improvements from the user's perspective). We focus instead on performance from the service provider's point of view (e.g, income from queries processed vs. resources used to answer them). We consider a scenario in which individual search engines compete for user queries by choosing which documents (topics) to index. The difficulty here stems from the fact that the utilities of local engine actions should depend on the uncertain actions of competitors. Thus, naive strategies (e.g, blindly indexing lots of popular documents) are ineffective. We model the competition between search engines as a stochastic game, and propose a reinforcement learning approach to managing search index contents. We evaluate our approach using a large log of user queries to 47 real search engines.