ppxscal/embedding_network huggingface dataset:
A statistical approach to spoken dialog systems design and evaluation
Authors: David Griol, Lluís F. Hurtado, Encarna Segarra, Emilio Sanchis
Venue: Speech Communication (2008)

In this paper, we present a statistical approach for the development of a dialog manager and for learning optimal dialog strategies. This methodology is based on a classification procedure that considers all of the previous history of the dialog to select the next system answer. To evaluate the performance of the dialog system, the statistical approach for dialog management has been extended to model the user behavior. The statistical user simulator has been used for the evaluation and improvement of the dialog strategy. Both the user model and the system model are automatically learned from a training corpus that is labeled in terms of dialog acts. New measures have been defined to evaluate the performance of the dialog system. Using these measures, we evaluate both the quality of the simulated dialogs and the improvement of the new dialog strategy that is obtained with the interaction of the two modules. This methodology has been applied to develop a dialog manager within the framework of the DIHANA project, whose goal is the design and development of a dialog system to access a railway information system using spontaneous speech in Spanish. We propose the use of corpus-based methodologies to develop the main modules in the dialog system.
Hierarchy-Driven Approach for Attack Patterns in Software Security Education
Authors: Joshua James Pauli, Patrick Henry Engebretson
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

We propose a hierarchy-driven approach to facilitate student learning and foster a deeper understanding of the importance of attack patterns in computer, network, and software security. This is a fundamental point in computer and software security education because the “patch and pray” mentality of software security is insufficient. The importance and significance of our approach is justified by accentuating the deficiencies in previous ad-hoc approaches to teaching attack patterns. Because of the vast amount of information in attack pattern repositories, it is unrealistic to expect students to fully comprehend attack pattern fundamentals and its place in computer, network, and software security.
Using Dynamic Condor-Based Services for Classifying Schizophrenia in Diffusion Tensor Images
Authors: Simon Caton, Matthan Caan, Sílvia Olabarriaga, Omer Rana, Bruce Batchelor
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

Diffusion Tensor Imaging (DTI) provides insight into the white matter of the human brain, which is affected by Schizophrenia. By comparing a patient group to a control group, the DTI-images are on average expected to be different for white matter regions. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) are used to classify the groups. In this work, the number of principal components is optimised for obtaining the minimal classification error. A robust estimate of this error is computed in a cross-validation framework, using different compositions of the data into a training and a testing set. Previously, sequential runs were performed in MATLAB, resulting in long execution times. In this paper we describe an experiment where this application was run on a grid with minimal modifications and user effort. We have adopted a service-based approach that autonomously launches Image Analysis Services onto a campus-wide Condor pool comprising of volunteer resources. This allows high throughput analysis of our data in a dynamic resource pool. The challenge in adopting such an approach comes from the nature of the resources, which change randomly with time and thus require fault tolerance. Through this approach we have reduced the computation time of each dataset from 90 minutes to less than 10. A minimal classification error of 22\% was obtained, using 15 principal components.
Analysis of the relationship between spatial pattern and spectral detectability of areas burned in southern Africa using satellite data
Authors: A. C. L. Sá, J. M. C. Pereira, R. H. Gardner
Venue: International Journal of Remote Sensing (2007)

Fires in Africa affect atmospheric emissions and carbon sequestration, landscape patterns, and regional and global climatic conditions. Studies of these effects require accurate estimation of the extent of measurable fire events. The goal of this study was to assess the influence of burned area spatial patterns on the spectral detectability of burned areas. Six Landsat-7 ETM+ images from the southern Africa were used for burned area mapping and spatial pattern analysis, while contemporaneous MODIS 500 m spatial resolution images were used to measure the spectral detectability of burned areas. Using a 15 by 15 km sample quadrats analysis, we showed that above a burned area proportion threshold of approximately 0.5 the spectral detectability of burned areas increase due to the decrease in the number of mixed pixels. This was spatially related to the coalescence of burned patches and the decrease in the total burned area perimeter. Simple burned area shapes were found at the Botswana site, where the absence of tree cover and the presence of bright surfaces (soil and dry grass) enhanced the spectral contrast of the burned surfaces, thus enabling better estimates of burned area extent. At the Zambia and Congo sites, landscape fragmentation due to human activity and the presence of a tree vegetation layer, respectively, contribute to the presence of small burned area patches, which may remain undetectable using moderate spatial resolution satellite imagery, leading to less accurate burned area extent estimates.
Dimension Reduction and Expansion: Distributed Source Coding in a Noisy Environment
Authors: Anna N. Kim, Fredrik Hekland
Venue: Proceedings of the Data Compression Conference (2008)

We studied the problem of distributed coding and transmission of inter-correlated sources with memory. Different from the conventional distributed source coding structure which relies on design of effective channel codes to model the inter-correlation and quantizer, the proposed system utilizes distributed compressed sensing [DCS06] for signal dimension reduction through linearmatrix operations and dimension expansion for protection against channel noise through a hybrid scalar quantizer linear coder [Coward00]. The proposed system is optimized for minimum end-to-end distortion under a transmission energy constraint. Itsperformance is verified through simulation and can serve as a good starting point for designing similar analogue based dimension reduction-expansion schemes for applications in sensor networks.
A simple method for representing some univariate frequency distributions, with particular application in Monte Carlo-based simulation
Authors: John C. Tipper
Venue: Computers Geosciences (2008)

Introduced in this paper is a simple yet effective method for representing some of the types of univariate frequency distribution that commonly are required in Monte Carlo-based simulation. To use the method, an appropriate parent distribution is first chosen; then this distribution is modified by blending a constant value into the density function; the particular value used is the ordinate of the density function at its mode. The advantages of the method are (1) that a wide variety of forms of distribution can be represented, (2) that the number of parameters is low, (3) that the parameters can be varied continuously to let sets of systematically related distributions be constructed, and (4) that the resulting distribution functions are straightforward to invert numerically, thereby letting random deviates be generated quickly and efficiently. The method is potentially of particular value in Monte Carlo-based simulation, because it allows distributions of greatly differing forms to be represented within a single, flexible framework. The paper describes the method, provides the necessary equations for parameter estimation, and gives an example of a simulation exercise in which the method proved valuable. A demonstration program is provided that allows experimentation with the method.
The LiteOS Operating System: Towards Unix-Like Abstractions for Wireless Sensor Networks
Authors: Qing Cao, Tarek Abdelzaher, John Stankovic, Tian He
Venue: Proceedings of the 7th international conference on Information processing in sensor networks (2008)

This paper presents LiteOS, a multi-threaded operating system that provides Unix-like abstractions for wireless sensor networks. Aiming to be an easy-to-use platform, LiteOS offers a number of novel features, including: (1) a hierarchical file system and a wireless shell interface for user interaction using UNIX-like commands; (2) kernel support for dynamic loading and native execution of multithreaded applications; and (3) online debugging, dynamic memory, and file system assisted communication stacks. LiteOS also supports software updates through a separation between the kernel and user applications, which are bridged through a suite of system calls. Besides the features that have been implemented, we also describe our perspective on LiteOS as an enabling platform. We evaluate the platform experimentally by measuring the performance of common tasks, and demonstrate its programmability through twenty-one example applications.
A New Framework for Theory-Based Interaction Design Applied to Serendipitous Information Retrieval
Authors: Oscar De Bruijn, Robert Spence
Venue: ACM Transactions on Computer-Human Interaction (TOCHI) (2008)

The activities of opportunistic and involuntary browsing offer the potential for many of a user's latent problems to be resolved serendipitously, with negligible cognitive effort. In this article, we demonstrate how the design of two novel artifacts to support such behavior was based on a set of Design Actions which were derived from a model of browsing behavior in combination with a cognitive model of human visual information processing. We propose the concept of Design Actions as a way of avoiding the need for an interaction designer associated with these and similar artifacts to understand the cognitive theories underlying them.
Schedulability issues for EDZL scheduling on real-time multiprocessor systems
Authors: Yi-Hsiung Chao, Shun-Shii Lin, Kwei-Jay Lin
Venue: Information Processing Letters (2008)

EDZL (Earliest Deadline first until Zero Laxity) is an efficient and practical scheduling algorithm on multiprocessor systems. It has a comparable number of context switch to EDF (Earliest Deadline First) and its schedulable utilization seems to be higher than that of EDF. Previously, there was a conjecture that the utilization bound of EDZL is 3m/4=0.75m for m processors. In this paper, we disprove this conjecture and show that the utilization bound of EDZL is no greater than m(1-1/e)~0.6321m, where e~2.718 is the Euler's number.
Color mixing property of a projector-camera system
Authors: Xinli Chen, Xubo Yang, Shuangjiu Xiao, Meng Li
Venue: Proceedings of the 5th ACM/IEEE International Workshop on Projector camera systems (2008)

In this paper, we investigate the property of how color channels of a projector-camera system interact with each other, which is also called color mixing of the system. We propose a method to describe this property with a single color mixing matrix for the system, rather than a different matrix for every surface point. The matrix is independent of projection surface and ambient light. It can be measured just like response functions of projector-camera system. The matrix is helpful for color sensitive applications like radiometric compensation and scene reconstruction. By decoupling color channels with the matrix of the system, color images can be processed on each channel separately just like gray images. As most projector-camera systems have broad overlap color channels, it's improper to neglect their interactions. We will show the validity of describing color mixing of the system with a single matrix. In the end, some experiments are designed to verify our method. The result is convincing.
Towards Comprehensive Requirement Analysis for Data Warehouses: Considering Security Requirements
Authors: Emilio Soler, Veronika Stefanov, Jose-Norberto Mazon, Juan Trujillo, Eduardo Fernandez-Madina, Mario Piattini
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

Data warehouse (DW) systems integrate data from heterogeneous sources and are used by decision makers to analyze the status and the development of an organization. Traditionally, requirement analysis approaches for DWs have focused purely on information needs of decision makers, without considering other kinds of requirements such as security or performance. But modeling these issues in the early stages of the development is a cornerstone for building a DW that satisfies user expectations. In this paper, we define the two kinds of requirements for data warehousing as information and quality-of-service requirements and combine them in a comprehensive approach based on MDA (Model Driven Architecture). This allows a separation of concerns to model requirements without losing the connection between information and quality-of-service, also in the following conceptual or logical design stages. Finally, in this paper, we introduce a security requirement model for data warehousing, and a three-step process for modeling security requirements, thus illustrating the applicability of our approach with an example.
An improvement of the crossing number bound
Authors: Bernard Montaron
Venue: Journal of Graph Theory (2005)

The crossing number cr(G) of a simple graph G with n vertices and m edges is the minimum number of edge crossings over all drawings of G on the ℝ2 plane. The conjecture made by Erd&otilde;s in 1973 that cr(G) &ge; Cm3-n2 was proved in 1982 by Leighton with C = 1-100 and this constant was gradually improved to reach the best known value C = 1-31.08 obtained recently by Pach, Radoicčić, Tardos, and T&oacute;th [4] for graphs such that m &ge; 103n-16. We improve this result with values for the constant in the range 1-31.08 &le; C < 1-15 where C depends on m-n2. For example, C > 1-25 for graphs with m-n2 > 0.291 and n > 22, and C > 1-20 for dense graphs with m-n2 e 0.485. &copy; 2005 Wiley Periodicals, Inc. J Graph Theory
Treatment of the initial value in Time-Memory-Data Tradeoff attacks on stream ciphers
Authors: Orr Dunkelman, Nathan Keller
Venue: Information Processing Letters (2008)

Time-Memory Tradeoff (TMTO) attacks on stream ciphers are a serious security threat and the resistance to this class of attacks is an important criterion in the design of a modern stream cipher. TMTO attacks are especially effective against stream ciphers where a variant of the TMTO attack can make use of multiple data to reduce the off-line and the on-line time complexities of the attack (given a fixed amount of memory). In this paper we present a new approach to TMTO attacks against stream ciphers using a publicly known initial value (IV): We suggest not to treat the IV as part of the secret key material (as done in current attacks), but rather to choose in advance some IVs and apply a TMTO attack to streams produced using these IVs. We show that while the obtained tradeoff curve is identical to the curve obtained by the current approach, the new technique allows to mount the TMTO attack in a larger variety of settings. For example, if both the secret key and the IV are of length n, it is possible to mount an attack with data, time, and memory complexities of 2^4^n^/^5, while in the current approach, either the time complexity or the memory complexity is not less than 2^n.
A note on Ramsey numbers for books
Authors: Vladimir Nikiforov, Cecil C. Rousseau
Venue: Journal of Graph Theory (2005)

The book with n pages Bn is the graph consisting of n triangles sharing an edge. The book Ramsey number r(Bm,Bn) is the smallest integer r such that either Bm&thinsp;&sub;&thinsp;G or Bn&thinsp;&sub;&thinsp; <ovbar>G</ovbar> for every graph G of order r. We prove that there exists a positive constant c such that r(Bm,Bn)&thinsp;=&thinsp;2n&thinsp;+&thinsp;3 for all n&thinsp;&ge;&thinsp;cm. Our proof is based mainly on counting; we also use a result of Andr&aacute;sfai, Erd&odblac;s, and S&oacute;s stating that triangle-free graphs of order n and minimum degree greater than 2n-5 are bipartite. &copy; 2005 Wiley Periodicals, Inc. J Graph Theory
A Theoretical Analysis of Data Reduction Using the Weber Quantizer
Authors: Julius Kammerl, Peter Hinterseer, Subhasis Chaudhuri, Eckehard Steinbach
Venue: Proceedings of the Data Compression Conference (2008)

We present a theoretical analysis of a perceptual coding approach, the so called Weber quantizer. It is based on Weber's Law and can be used in haptic data communication to eliminate changes which cannot be perceived by a human being. The main advantage of the Weberquantizer is that it minimizes the number of samples or packets to be processed and transmitted. Basic properties like the resulting sample rate of the proposed Weber quantizer are derived analytically and proven correct by simulation for the case of an independently and identically distributed (i.i.d.) input sequence. The contributions in this paper are a step towards the understanding of the relationship between the Weber quantizer and its update rate savings.
Dissolution point and isolation robustness: Robustness criteria for general cluster analysis methods
Authors: Christian Hennig
Venue: Journal of Multivariate Analysis (2008)

Two robustness criteria are presented that are applicable to general clustering methods. Robustness and stability in cluster analysis are not only data dependent, but even cluster dependent. Robustness is in the present paper defined as a property of not only the clustering method, but also of every individual cluster in a data set. The main principles are: (a) dissimilarity measurement of an original cluster with the most similar cluster in the induced clustering obtained by adding data points, (b) the dissolution point, which is an adaptation of the breakdown point concept to single clusters, (c) isolation robustness: given a clustering method, is it possible to join, by addition of g points, arbitrarily well separated clusters? Results are derived for k-means, k-medoids (k estimated by average silhouette width), trimmed k-means, mixture models (with and without noise component, with and without estimation of the number of clusters by BIC), single and complete linkage.
Creating and sharing multi-media packages using large situated public displays and mobile phones
Authors: Andrew Maunder, Gary Marsden, Richard Harper
Venue: Proceedings of the 9th international conference on Human computer interaction with mobile devices and services (2007)

This paper will describe a novel interaction technique that allows mobile phone users to create and share contextualised media packages between their personal, BlueTooth enabled camera phones, and situated public displays. Unlike other solutions to this problem, the one presented in this paper does not require any specialist software or hardware on the user's handset. We believe this technique has the potential to revolutionise how people donate and retrieve digital media files without incurring any direct cost.
Speed-up of memory failure shape analysis
Authors: Jyh-Ming Jang, Hsing-Chung Liang, Hwang-Cherng Chow
Venue: Proceedings of the 9th International Conference on Circuits (2005)

A failure shape analysis system is developed to quickly analyze the defect distribution of memories. Compared to the original system, the newer one consists of several programs feasible both on workstations and PCs. These programs transform and grasp the required data for further failure analysis. The complete system is highly reliable and fault tolerant for the entire manufacture and test procedure. It can achieve the similar defect distribution as the original one but with only 11% and 6% of run time on workstations and PCs, respectively.
An algorithmic approach to constructing mixed-level orthogonal and near-orthogonal arrays
Authors: Nam-Ky Nguyen, Min-Qian Liu
Venue: Computational Statistics Data Analysis (2008)

Due to run size constraints, near-orthogonal arrays (near-OAs) and supersaturated designs, a special case of near-OA, are considered good alternatives to OAs. This paper shows (i) a combinatorial relationship between a mixed-level array and a non-resolvable incomplete block design (IBD) with varying replications (and its dual, a resolvable IBD with varying block sizes); (ii) the relationship between the criterion E(d^2) proposed by Lu and Sun [Lu, X., Sun, Y., 2001. Supersaturated designs with more than two levels. Chinese Ann. Math. B 22, 183-194] or E(f"""N"""O"""D) proposed by Fang et al. [Fang, K.T., Lin, D.K.J., Liu, M.Q., 2003b. Optimal mixed-level supersaturated design. Metrika 58, 279-291] used in the (near-) OA construction and the (M,S)-optimality criterion used in the IBD construction; (iii) the derivation of a tighter bound for E(d^2); (iv) how to modify the IBD algorithm of Nguyen [Nguyen, N.-K., 1994. Construction of optimal incomplete block designs by computer. Technometrics 36, 300-307] to obtain efficient (near-) OA algorithms. Some new (near-) OAs are presented and some near-OAs are compared with arrays constructed by other authors. Examples showing the use of the constructed arrays are given.
Artificial institutions: a model of institutional reality for open multiagent systems
Authors: Nicoletta Fornara, Francesco Viganò, Mario Verdicchio, Marco Colombetti
Venue: Artificial Intelligence and Law (2008)

Software agents' ability to interact within different open systems, designed by different groups, presupposes an agreement on an unambiguous definition of a set of concepts, used to describe the context of the interaction and the communication language the agents can use. Agents' interactions ought to allow for reliable expectations on the possible evolution of the system; however, in open systems interacting agents may not conform to predefined specifications. A possible solution is to define interaction environments including a normative component, with suitable rules to regulate the behaviour of agents. To tackle this problem we propose an application-independent metamodel of artificial institutions that can be used to define open multiagent systems. In our view an artificial institution is made up by an ontology that models the social context of the interaction, a set of authorizations to act on the institutional context, a set of linguistic conventions for the performance of institutional actions and a system of norms that are necessary to constrain the agents' actions.