ppxscal/embedding_network huggingface dataset:
Non-negative mixed finite element formulations for a tensorial diffusion equation
Authors: K. B. Nakshatrala, A. J. Valocchi
Venue: Journal of Computational Physics (2009)

We consider the tensorial diffusion equation, and address the discrete maximum-minimum principle of mixed finite element formulations. In particular, we address non-negative solutions (which is a special case of the maximum-minimum principle) of mixed finite element formulations. It is well-known that the classical finite element formulations (like the single-field Galerkin formulation, and Raviart-Thomas, variational multiscale, and Galerkin/least-squares mixed formulations) do not produce non-negative solutions (that is, they do not satisfy the discrete maximum-minimum principle) on arbitrary meshes and for strongly anisotropic diffusivity coefficients. In this paper, we present two non-negative mixed finite element formulations for tensorial diffusion equations based on constrained optimization techniques. These proposed mixed formulations produce non-negative numerical solutions on arbitrary meshes for low-order (i.e., linear, bilinear and trilinear) finite elements. The first formulation is based on the Raviart-Thomas spaces, and the second non-negative formulation is based on the variational multiscale formulation. For the former formulation we comment on the effect of adding the non-negative constraint on the local mass balance property of the Raviart-Thomas formulation. We perform numerical convergence analysis of the proposed optimization-based non-negative mixed formulations. We also study the performance of the active set strategy for solving the resulting constrained optimization problems. The overall performance of the proposed formulation is illustrated on three canonical test problems.
Supporting Exploration Awareness in Information Visualization
Authors: Yedendra Babu Shrinivasan, Jarke van Wijk
Venue: IEEE Computer Graphics and Applications (2009)

When users want to continue an analysis performed in the past, done by themselves or by a collaborator, they need an overview of what has been done and found so far. Such an overview helps them to gain a shared knowledge about each others&#x2019; analysis strategy and continue the analysis. We aim to support users in this process, and thereby support their exploration awareness. We present an information visualization framework with three linked processes: overview, search and retrieve for this purpose. First, we present a user&#x2019;s information interest model that captures key aspects of the exploration process. Exploration overview, and keyword and similarity based search mechanisms are designed based on these key aspects. A metadata view is used to visualize the search results and help users to retrieve specific visualizations from past analysis. Finally, we present three case studies and discuss the support offered by the framework for developing exploration awareness.
Workshop Organizers' Message
Authors: Dickson K. Chiu, Yi Zhuang
Venue: Database Systems for Advanced Applications: DASFAA 2009 International Workshops: BenchmarX, MCIS, WDPP, PPDA, MBC, PhD, Brisbane, Australia, April 20 - 23, 2009 (2009)

The recent advancement of workflow technologies and adoption of the Service-Oriented Architecture (SOA) has much facilitated the automation of business collaboration within and across organizations to increase their competiveness and responsiveness to the fast evolving global economic environment. The widespread of mobile technologies has further resulted in an increasing demand for the support of Mobile Business Collaboration (MBC) across multiple platforms anytime and anywhere. Examples include supply-chain logistics, group calendars, and dynamic human resources planning. As mobile devices become more powerful, the adoption of mobile computing is imminent. However, mobile business collaboration is not merely porting the software with an alternative user interface, but rather involves a wide range of new requirements, constraints, and technical challenges.
Creating Community through the Use of a Class Wiki
Authors: Kirsten A. Johnson, Jamie Bartolino
Venue: Proceedings of the 3d International Conference on Online Communities and Social Computing: Held as Part of HCI International 2009 (2009)

This study examines the use of a class wiki in a course offered to incoming freshmen at a college in central Pennsylvania. The wiki was used to supplement instruction in a classroom-based course. The study shows that the wiki was helpful in building community among incoming students, and also helped them to grow academically in the course. The class wiki also helped foster positive feelings toward the course as well as students' first semester at the college.
Study on Advanced Processing of Coking Wastewater Using Different Coagulants
Authors: Zheng Yi, Zhang Zhuo, Zhang Haiying, Hu Hongtao, Wei Xialiang
Venue: Proceedings of the 2009 International Conference on Environmental Science and Information Application Technology - Volume 01 (2009)

In this study, coking wastewater was treated using different coagulants to make it meet requirements of the secondary standard described in “Integrated wastewater discharge standard”. Coagulation using PFS and PACrespectively was performed to study effect of coagulant dosage, and pH on removal ratios of colority, CODcr and turbidity. It is found that optimum dosage and pH are 50 mg/L and 6 for PFS, and 75 mg/L and 8 for PAC. All effluent quality after coagulation at the optimum conditions meet requirements of the secondary standard described in “Integrated wastewater discharge standard”. Coagulation using PAC at the optimum conditions are recommended for advanced treatment of coking wastewater.
Studying feature generation from various data representations for answer extraction
Authors: Dan Shen, Geert-Jan M. Kruijff, Dietrich Klakow
Venue: Proceedings of the ACL Workshop on Feature Engineering for Machine Learning in Natural Language Processing (2005)

In this paper, we study how to generate features from various data representations, such as surface texts and parse trees, for answer extraction. Besides the features generated from the surface texts, we mainly discuss the feature generation in the parse trees. We propose and compare three methods, including feature vector, string kernel and tree kernel, to represent the syntactic features in Support Vector Machines. The experiment on the TREC question answering task shows that the features generated from the more structured data representations significantly improve the performance based on the features generated from the surface texts. Furthermore, the contribution of the individual feature will be discussed in detail.
A comparison of hedged and non-hedged NLG texts
Authors: Saad Mahamood, Ehud Reiter, Chris Mellish
Venue: Proceedings of the Eleventh European Workshop on Natural Language Generation (2007)

We assess the use of hedge phrases in "affective" NLG texts. A simple experiment suggests non-native speakers prefer texts that contain hedge phrases, but native speakers prefer texts that do not contain hedge phrases.
Perceptron training for a wide-coverage lexicalized-grammar parser
Authors: Stephen Clark, James R. Curran
Venue: Proceedings of the Workshop on Deep Linguistic Processing (2007)

This paper investigates perceptron training for a wide-coverage CCG parser and compares the perceptron with a log-linear model. The CCG parser uses a phrase-structure parsing model and dynamic programming in the form of the Viterbi algorithm to find the highest scoring derivation. The difficulty in using the perceptron for a phrase-structure parsing model is the need for an efficient decoder. We exploit the lexicalized nature of CCG by using a finite-state supertagger to do much of the parsing work, resulting in a highly efficient decoder. The perceptron performs as well as the log-linear model; it trains in a few hours on a single machine; and it requires only a few hundred MB of RAM for practical training compared to 20 GB for the log-linear model. We also investigate the order in which the training examples are presented to the online perceptron learner, and find that order does not significantly affect the results.
Contemporary technologies for 3D digitization of Maori and Pacific Island artifacts
Authors: Nanda K. Surendran, Xun W. Xu, Oliver Stead, Heather Silyn-Roberts
Venue: International Journal of Imaging Systems and Technology (2009)

Three-dimensional (3D) digitization is a key aspect in the preservation and exhibition of museum artifacts. The objective of this article is to investigate contemporary technologies for creating accurate 3D digital models of artifacts from the Maori and Pacific heritage and to establish a generic digitization methodology so that the 3D models can be archived and exhibited both over the internet and within museum displays. This process involves procedures for selecting artifacts that are suitable for laser scanning and then setting up the artifact for scanning. This is followed by the actual scanning and postprocessing stages. To achieve this, the Polhemus FastSCAN laser scanner has been used to collect raw point cloud surface data from artifacts of various sizes, shapes, textures, colors, and materials. The article explains the generic steps developed for postprocessing of raw scan data in the form of a cloud of geometric data points to a completely rendered 3D model with colors mapped on to the model. These generic steps involve removal of background noise, enhancement of texture, filling of holes, merging of separate scans, and color mapping. The results from the scanning and postprocessing of a wahaika, (a Maori club-like weapon) and a Polynesian stone pounder reveal that it is important to use a scanner that is flexible enough to capture all the surface information irrespective of the artifact's geometry, and one with the capability of capturing color information with high accuracy. &copy; 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 244&ndash;259, 2009
Relations Among Privacy Notions
Authors: Jens-Matthias Bohli, Andreas Pashalidis
Venue: Financial Cryptography and Data Security: 13th International Conference, FC 2009, Accra Beach, Barbados, February 23-26, 2009. Revised Selected Papers (2009)

This paper presents a hierarchy of privacy notions that covers multiple anonymity and unlinkability variants. The underlying definitions, which are based on the idea of indistinguishability between two worlds, provide new insights into the relation between, and the fundamental structure of, different privacy notions. We apply our definitions to group signatures and anonymous communication systems, and show how they relate to existing definitions.
Intelligent Agents for Training On-Board Fire Fighting
Authors: Karel Bosch, Maaike Harbers, Annerieke Heuvelink, Willem Doesburg
Venue: Proceedings of the 2nd International Conference on Digital Human Modeling: Held as Part of HCI International 2009 (2009)

Simulation-based training in complex decision making often requires ample personnel for playing various roles (e.g. team mates, adversaries). Using intelligent agents may diminish the need for staff. However, to achieve goal-directed training, events in the simulation as well as the behavior of key players must be carefully controlled. We propose to do that by using a director agent (DA). A DA can be seen as a supervisor, capable of instructing agents and steering the simulation. We explain and illustrate the concept in the context of training in on-board fire fighting.
A Detailed Analysis of Two Metaheuristics for the Team Orienteering Problem
Authors: Pieter Vansteenwegen, Wouter Souffriau, Dirk Oudheusden
Venue: Proceedings of the Second International Workshop on Engineering Stochastic Local Search Algorithms. Designing, Implementing and Analyzing Effective Heuristics (2009)

This paper presents different techniques that can be used to improve the metaheuristic design and insight in the problem at hand. The presented techniques are applied to analyse the performance of two different metaheuristics for the team orienteering problem. Furthermore, the parameter setting problem is discussed and the parameter "sensitivity" is analysed.
SWAT-MP: the SemEval-2007 systems for task 5 and task 14
Authors: Phil Katz, Matthew Singleton, Richard Wicentowski
Venue: Proceedings of the 4th International Workshop on Semantic Evaluations (2007)

In this paper, we describe our two SemEval-2007 entries. Our first entry, for Task 5: Multilingual Chinese-English Lexical Sample Task, is a supervised system that decides the most appropriate English translation of a Chinese target word. This system uses a combination of Na&iuml;ve Bayes, nearest neighbor cosine, decision lists, and latent semantic analysis. Our second entry, for Task 14: Affective Text, is a supervised system that annotates headlines using a predefined list of emotions. This system uses synonym expansion and matches lemmatized unigrams in the test headlines against a corpus of hand-annotated headlines.
An Immune Approach to Recognition of Handwritten Words
Authors: Andrzej Chmielewski, Slawomir T. Wierzchon
Venue: Proceedings of the 2009 International Conference on Biometrics and Kansei Engineering (2009)

This paper presents an immune-based approach to recognition of handwritten words, or more generally, to binary classification. It is inspired by the negative selection mechanism attending the discrimination between self and nonself molecules in living organisms.Our approach incorporates two types of detectors: binary and real-valued. Relatively short binary detectors are used for primary detection, while the real valued detectors are used to resolve eventual doubts. Such a hybrid solution is much more economical in comparison with "pure" approaches. The binary detectors are faster than real-valued ones with respect to the number of operations needed to compare two items. Thus, we gain simplicity and speed of comparisons.
k-Subgraph Isomorphism on AC_0 Circuits
Authors: Kazuyuki Amano
Venue: Proceedings of the 2009 24th Annual IEEE Conference on Computational Complexity (2009)

Recently, Rossman [STOC '08] established a lower bound of $\omega(n^{k/4})$ on the size of constant-depth circuits for the $k$-clique function on $n$-vertex graphs, which is the first lower bound that does not depend on the depth of circuits in the exponent of $n$. He showed, in fact, a stronger statement: Suppose $f_n:\{0,1\}^{n \choose 2} \rightarrow \{0,1\}$ is a sequence of functions computed by constant-depth circuits of size $O(n^t)$. For any positive integer $k$ and $0
Intensive Tillage Effects on Wheat Production on a Steep Hillslope in the Sichuan Basin, China
Authors: Xiaojun Nie, Jianhui Zhang, Zhengan Su
Venue: Proceedings of the 2009 International Conference on Environmental Science and Information Application Technology - Volume 01 (2009)

Two treatments (5- and 15-tillage operations) were conducted to assess intensive tillage effects on wheat production in the Sichuan Basin, China. After intensive tillage, wheat grain yields were 55% and 41% in areas of soil loss lower than those in areas of soil accumulation by 5- and 15-tillage operations, respectively. The redistribution pattern in soil depth affected wheat production with a logarithmic correlation between them, resulting in wheat aboveground biomass and grain yield increased along the downslope transect. A much larger decline in production with loss of soil depth than the increase in production with increase in depth was found. Therefore, fields subject to these patterns of soil redistribution could be expected to be subject to decline in average yield. The variations suggest that over time crop production reduction would gradually become serious in areas of soil loss by tillage.
Future Ability Requirements for Human Operators in Aviation
Authors: Catrin Hasse, Carmen Bruder, Dietrich Grasshoff, Hinnerk Eißfeldt
Venue: Proceedings of the 8th International Conference on Engineering Psychology and Cognitive Ergonomics: Held as Part of HCI International 2009 (2009)

The present study addresses the optimal fit between technical innovations in aviation and aircraft operators. Because of the increase in computerization, an accurate and efficient monitoring of the automation poses a key challenge to future operators. As the German Aerospace Center's Department of Aviation and Space Psychology is responsible for personnel selection of pilots and air traffic controllers, our objective for the selection of future personnel is to distinguish good monitoring operators from bad operators. In order to identify good monitoring behavior we developed a simulation tool that represents tasks of pilots and controllers within a dynamic air traffic flow. Participants have either to monitor the automatic process or to control the dynamic traffic manually. Monitoring behavior is measured by recording eye movement parameters. The identification of accurate monitoring behavior enables us to adapt selection profiles to future ability requirements.
Comparison of String Distance Metrics for Lemmatisation of Named Entities in Polish
Authors: Jakub Piskorski, Marcin Sydow, Karol Wieloch
Venue: Human Language Technology. Challenges of the Information Society: Third Language and Technology Conference, LTC 2007, Poznan, Poland, October 5-7, 2007, Revised Selected Papers (2009)

This paper presents the results of recent experiments on application of string distance metrics to the problem of named entity lemmatisation in Polish. It extends of our work in [1] by introducing new results for organisation names. Furthermore, the results presented here and in [2,3] centering around the same topic were used to make a comparative study of the average usefulness of the numerous examined string distance metrics to lemmatisation of Polish named-entities of various types. In particular, we focus on lemmatisation of country names, organisation names and person names.
Type Analysis for JavaScript
Authors: Simon Holm Jensen, Anders Møller, Peter Thiemann
Venue: Proceedings of the 16th International Symposium on Static Analysis (2009)

JavaScript is the main scripting language for Web browsers, and it is essential to modern Web applications. Programmers have started using it for writing complex applications, but there is still little tool support available during development.We present a static program analysis infrastructure that can infer detailed and sound type information for JavaScript programs using abstract interpretation. The analysis is designed to support the full language as defined in the ECMAScript standard, including its peculiar object model and all built-in functions. The analysis results can be used to detect common programming errors --- or rather, prove their absence, and for producing type information for program comprehension.Preliminary experiments conducted on real-life JavaScript code indicate that the approach is promising regarding analysis precision on small and medium size programs, which constitute the majority of JavaScript applications. With potential for further improvement, we propose the analysis as a foundation for building tools that can aid JavaScript programmers.
Probabilistic Granule-Based Inside and Nearest Neighbor Queries
Authors: Sergio Ilarri, Antonio Corral, Carlos Bobed, Eduardo Mena
Venue: Proceedings of the 13th East European Conference on Advances in Databases and Information Systems (2009)

The development of location-based services and advances in the field of mobile computing have motivated an intensive research effort devoted to the efficient processing of location-dependent queries. In this context, it is usually assumed that location data are expressed at a fine geographic precision. Adding support for location granules means that the user is able to use his/her own terminology for locations (e.g., GPS, cities, states, provinces, etc.), which may have an impact in the semantics of the query, the way the results are presented, and the performance of the query processing.Along with its advantages, the management of the so-called location granules introduces new challenges for query processing. In this paper, we analyze two popular location-dependent constraints, inside and nearest neighbors, and enhance them with the possibility to specify location granules. In this context, we study the problem that arises when the locations of the objects are subject to some imprecision.
Design and Simulation of an Enhanced Handover Scheme in Heterogeneous Mobile IPv6 Networks
Authors: Xinyi Wu, Gang Nie
Venue: Proceedings of the 2009 Asia-Pacific Conference on Information Processing - Volume 02 (2009)

Mobile IPv6 provides IPv6 nodes with the ability to use home address to keep the connection while roaming between different subnet. The handover performance of mobile IPv6 is one of the key factors which guarantee the QoS of mobile Internet. In this paper, we propose an enhanced handover scheme in a heterogeneous mobile environment with the support of the Media Independent Handover (MIH)Services and Advance Duplicate Address Detection (A-DAD).The proposed scheme can reduce the handover latency in Mobile IPv6 greatly. We perform a simulation on handover between WiMAX and WLAN IEEE 802.11b with the proposed scheme in Mobile IPv6 to get handover performance in terms of handover latency.
Finding My Needle in the Haystack: Effective Personalized Re-ranking of Search Results in Prospector
Authors: Florian König, Lex Velsen, Alexandros Paramythis
Venue: Proceedings of the 10th International Conference on E-Commerce and Web Technologies (2009)

This paper provides an overview of Prospector, a personalized Internet meta-search engine, which utilizes a combination of ontological information, ratings-based models of user interests, and complementary theme-oriented group models to recommend (through re-ranking) search results obtained from an underlying search engine. Re-ranking brings "closer to the top" those items that are of particular interest to a user or have high relevance to a given theme. A user-based, real-world evaluation has shown that the system is effective in promoting results of interest, but lags behind Google in user acceptance, possibly due to the absence of features popularized by said search engine. Overall, users would consider employing a personalized search engine to perform searches with terms that require disambiguation and / or contextualization.
How to Encipher Messages on a Small Domain
Authors: Ben Morris, Phillip Rogaway, Till Stegers
Venue: Proceedings of the 29th Annual International Cryptology Conference on Advances in Cryptology (2009)

We analyze the security of the Thorp shuffle, or, equivalently, a maximally unbalanced Feistel network. Roughly said, the Thorp shuffle on N cards mixes any N 1 ¿ 1/r of them in $O(r\lg N)$ steps. Correspondingly, making O(r) passes of maximally unbalanced Feistel over an n-bit string ensures CCA-security to 2 n(1 ¿ 1/r) queries. Our results, which employ Markov-chain techniques, enable the construction of a practical and provably-secure blockcipher-based scheme for deterministically enciphering credit card numbers and the like using a conventional blockcipher.