ppxscal/embedding_network huggingface dataset:
Wireless LAN architecture for mobile operators
Authors: Juha Ala-Laurila, Henry Haverinen, Jouni Mikkonen, Jyri Rinnemaa
Venue: Wireless local area networks: the new wireless revolution (2002)

The evolution of Internet- or IP-based office applications has created a strong demand for public broadband wireless access offering capacity beyond current cellular systems. A wireless LAN is able to support broadband data rates in indoor environments but does not include support for operator-driven public access. In addition, most commercial public wireless LAN solutions only provide modest authentication and roaming capability compared with traditional cellular networks. This chapter describes a new wireless LAN system architecture that combines the wireless LAN radio access technology with the mobile operators' SIM-based subscriber management functions and roaming infrastructure. In the defined system, wireless LAN access is authenticated and charged with the GSM SIM, which is a widely deployed mobility platform. This solution supports roaming between cellular and wireless LAN access networks and is one step toward an all-IP network architecture. The first release of the system has been implemented and verified in an actual mobile operator network.
Embedded self-testing checkers for low-cost arithmetic codes
Authors: Steffen Tarnick, Albrecht P. Stroele
Venue: Proceedings of the 1998 IEEE International Test Conference (1998)

In highly reliable systems, error detecting codes are employed and errors caused by faultyhardware are indicated on-line by code checkers. Wepresent two novel architectures of embedded self-testingcheckers for low-cost arithmetic codes, one based oncode word generators and adders, the other based oncode word accumulators. In these schemes, the codechecker receives all possible code words but one, irrespective of the number of different code words that areproduced by the circuit under check (CUC). So anycode checker can be employed that is self-testing forall or a particular subset of code words, and the structure of the code checker need not be tailored to the setof code words produced by the CUC. The proposed codeword generators and accumulators are built from simple standard hardware structures, counters and end-around-carry adders. They can also be utilized in anoff-line BIST environment as pattern generators andtest response compactors.
Communication Patterns As Determinants of Organizational Identification in a Virtual Organization
Authors: Batia M. Wiesenfeld, Sumita Raghuram, Raghu Garud
Venue: Organization Science (1999)

Recent advances in information technologies provide employees the freedom to work from any place and at any time. Such temporal and spatial dispersion, however, weakens the ties that bind organizations and their members. We suggest that organizational identification may be the critical glue linking virtual workers and their organizations. We explore the role that information technologies play in the creation and maintenance of a common identity among decoupled organization members.
Feature subset selection using a new definition of classifiability
Authors: Ming Dong, Ravi Kothari
Venue: Pattern Recognition Letters (2003)

The performance of most practical classifiers improves when correlated or irrelevant features are removed. Machine based classification is thus often preceded by subset selection--a procedure which identifies relevant features of a high dimensional data set. At present, the most widely used subset selection technique is the so-called "wrapper" approach in which a search algorithm is used to identify candidate subsets and the actual classifier is used as a "black box" to evaluate the fitness of the subset. Fitness evaluation of the subset however requires cross-validation or other resampling based procedure for error estimation necessitating the construction of a large number of classifiers for each subset. This significant computational burden makes the wrapper approach impractical when a large number of features are present.In this paper, we present an approach to subset selection based on a novel definition of the classifiability of a given data. The classifiability measure we propose characterizes the relative ease with which some labeled data can be classified. We use this definition of classifiability to systematically add the feature which leads to the most increase in classifiability. The proposed approach does not require the construction of classifiers at each step and therefore does not suffer from as high a computational burden as a wrapper approach. Our results over several different data sets indicate that the results obtained are at least as good as that obtained with the wrapper approach.
Distributing CORBA views from an OODBMS
Authors: Eric Viara, Guy Vaysseix, Emmanuel Barillot
Venue: Proceedings of the 2002 International Symposium on Database Engineering & Applications (2002)

The need to distribute objects on the Internet and to offer views from databases has found a solution with the advent of CORBA. Most database management systems now offer CORBA interfaces which are generally simple mapping of the database schema to the CORBA world. This approach does not address all the problem of database interoperation because (i) such a view is static (ii) its semantic is completely bound to the semantic of the schema and it is not possible to re-model it (iii) only one view per database can be offered (iv) access may be limited to reading and no mechanism is given to write in the database through the view.To solve these problems, we have designed a language, the Interface Mapping Definition Language (IMDL) and some tools, grouped in the Interface Mapping Service (IMS). IMDL is used to define CORBA views from OODBMS, while IMS generates an IDL construct and a full CORBA implementation from an IMDL construct and a database schema.
Upwind Schemes with Exact Conservation Property for One-Dimensional Open Channel Flow Equations
Authors: Senka Vukovic, Luka Sopta
Venue: SIAM Journal on Scientific Computing (2002)

In this paper we present an application and extension of the upwind schemes with source terms decomposed, developed by Bermúdez, Vázquez, Hubbard, and Garcia-Navarro, to the one-dimensional open channel flow equations with general, i.e., nonprismatic and nonrectangular, geometries. Our specific numerical approximations for terms that appear in these equations and are related to the channel's geometrical properties are quite straightforward and natural, and at the same time respect the balancing of the flux gradient and the source term. As a consequence, the resulting upwind schemes have the exact conservation property. In several test problems we illustrate the achieved improvement, particularly significant for applications to natural watercourses due to their irregular riverbed geometries.
On producing join results early
Authors: Jens-Peter Dittrich, Bernhard Seeger, David Scot Taylor, Peter Widmayer
Venue: Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2003)

Support for exploratory interaction with databases in applications such as data mining requires that the first few results of an operation be available as quickly as possible. We study the algorithmic side of what can and what cannot be achieved for processing join operations. We develop strategies that modify the strict two-phase processing of the sort-merge paradigm, intermingling join steps with selected merge phases of the sort. We propose an algorithm that produces early join results for a broad class of join problems, including many not addressed well by hash-based algorithms. Our algorithm has no significant increase in the number of I/O operations needed to complete the join compared to standard sort-merge algorithms.
Space-varying regression models: specifications and simulation
Authors: Dani Gamerman, Ajax R. B. Moreira, Håvard Rue
Venue: Computational Statistics Data Analysis (2003)

Space-varying regression models are generalizations of standard linear models where the regression coefficients are allowed to change in space. The spatial structure is specified by a multivariate extension of pairwise difference priors, thus enabling incorporation of neighboring structures and easy sampling schemes. Bayesian inference is performed by incorporation of a prior distribution for the hyperparameters. This approach leads to an untractable posterior distribution. Inference is approximated by drawing samples from the posterior distribution. Different sampling schemes are available and may be used in an MCMC algorithm. They basically differ in the way they handle blocks of regression coefficients. Approaches vary from sampling each location-specific vector of coefficients to complete elimination of all regression coefficients by analytical integration. These schemes are compared in terms of their computation, chain auto-correlation, and resulting inference. Results are illustrated with simulated data and applied to a real dataset. Related prior specifications that can accommodate the spatial structure in different forms are also discussed. The paper concludes with a few general remarks.
Identification problem for the wave equation with Neumann data input and Dirichlet data observations
Authors: Xiaobing Feng, Suzanne Lenhart, Vladimir Protopopescu, Lizabeth Rachele, Brian Sutton
Venue: Nonlinear Analysis: Theory, Methods Applications (2003)

We seek to identify the dispersive coefficient in a wave equation with Neumann boundary conditions in a bounded space-time domain from imprecise observations of the solution on the boundary of the spatial domain (Dirichlet data). The problem is regularized and solved by casting it into an optimal control setting. By letting the "cost of the control" tend to zero, we obtain the limit of the corresponding control sequence, which we identify with the sought dispersive coefficient. The corresponding solution of the wave equation is interpreted as the possibly nonunique projection of the observation vector onto the range of the Neumann-to-Dirichlet maps corresponding to a single input Neumann data, as the dispersive coefficient is varied. Several numerical examples illustrate the merits and limitations of the procedure.
Using semantic and phonetic term similarity for spoken document retrieval and spoken query processing
Authors: Fabio Crestani
Venue: Technologies for constructing intelligent systems: Tasks (2002)

In classical Information Retrieval systems a relevant document will not be retrieved in response to a query if the document and query representations do not share at least one term. This problem is known as "term mismatch". A similar problem can be found in spoken document retrieval and spoken query processing, where terms misrecognized by the speech recognition process can hinder the retrieval of potentially relevant documents. I will call this problem "term misrecognition", by analogy to the term mismatch problem.This paper presents two classes of retrieval models that attempt to tackle both the term mismatch and the term misrecognition problems at retrieval time using term similarity information. The models make effective use of complete or partial knowledge of semantic and phonetic term similarity evaluated using statistical methods for the corpus.
Evaluation of a novel technique for measuring reaeration in rivers
Authors: P. A. Mackinnon, T. Elliot, Y. Q. Zhao, J. L. Murphy, R. M. Kalin
Venue: Development and application of computer techniques to environmental studies (2002)

Depletion of dissolved oxygen (DO) is one of the most common forms of river pollution. In extreme cases, it can result in fish kills, foul odours and can prohibit the use of water for drinking and other purposes. Regulatory authorities therefore place great importance on their ability to predict depletion of DO in waters which receive wastewater discharges and agricultural runoff.To date, predictive water quality models have relied almost totally on empirical methods to estimate the overall controlling factor for mass transfer of oxygen from the atmosphere into water bodies, the reaeration coefficient (K2). However, this coefficient varies from one river to another and changes with changing hydraulic conditions within a reach. Poor estimates have often led to inaccurate predictions of water quality.This paper describes the development of a novel method for the direct measurement of the reaeration coefficient in any river. This direct approach utilises two tracers - one volatile, one conservative - but, unlike previous tracer studies reported by other authors, it does not rely on the use of radioactive materials to achieve sensitive and precise measurement. Instead both tracers used are generally deemed 'environmentally friendly': the inert gas, Krypton, and the recognised fluorescent water tracer, Rhodamine WT, are used to quantify the reaeration coefficient. The adopted method is based on highly sensitive measurements of these substances using Gas Chromatography Mass Spectrometry (GC-MS) and fluorimetry techniques respectively.The outcome of field tests in a major river in Northern Ireland is reported. Issues affecting the precision of the method are addressed and the practicalities of applying it are discussed.
A Staggered Ordering Policy for One-Warehouse, Multiretailer Systems
Authors: Fangruo Chen, Rungson Samroengraja
Venue: Operations Research (2000)

We consider a one-warehouse,N-identical-retailer model. Random demands occur at the retailers with complete backlogging. The retailers replenish their inventories from the warehouse, which in turn orders from an outside supplier with unlimited stock. Each retailer places an order everyN periods according to a base-stock policy, and the reorder intervals of the retailers are staggered so that only one retailer places an order in each period. The warehouse orders according to an ( s, S) policy based on its own inventory position. We consider two allocation policies, past priority allocation (PPA) and current priority allocation (CPA), which specify how the retailer orders are filled at the warehouse. For the PPA model, we provide an exact procedure for computing the long-run average total cost. Based on the exact procedure, we develop an approximate model that can be used to determine near-optimal control parameters for both the PPA and the CPA model. We conduct a computational study to test the effectiveness of the approximate model and to compare the performance of the two allocation policies.
Corporate Championing and Antagonism as Forms of Political Behavior: An R&D Perspective
Authors: Stephen K. Markham
Venue: Organization Science (2000)

Individuals in general management, marketing, production, and customer service undertake corporate political roles of championing and antagonism in support of or opposition to research and development (R&D) projects. R&D personnel see these champions acting politically because they favor projects that align more closely with the firm's business interests than with its specific technologies. Champions find resources and protect their projects from termination; however, they are equally likely to support high and low performing projects. These results contradict many of the commonly held beliefs in research literature about champions. Antagonists, in a role of friendly opposition, appear to react to the presence of champions and do not appear to affect resources or project termination.
Order-based fitness functions for genetic algorithms applied to relevance feedback
Authors: Cristina López-Pujalte, Vicente P. Guerrero-Bote, Félix de Moya-Anegón
Venue: Journal of the American Society for Information Science and Technology (2003)

Recently there have been appearing new applications of genetic algorithms to information retrieval, most of them specifically to relevance feedback. The evolution of the possible solutions are guided by fitness functions that are designed as measures of the goodness of the solutions. These functions are naturally the key to achieving a reasonable improvement, and which function is chosen most distinguishes one experiment from another. In previous work, we found that, among the functions implemented in the literature, the ones that yield the best results are those that take into account not only when documents are retrieved, but also the order in which they are retrieved. Here, we therefore evaluate the efficacy of a genetic algorithm with various order-based fitness functions for relevance feedback (some of them of our own design), and compare the results with the Ide dec-hi method, one of the best traditional methods.
Perception differences of software success: provider and user views of system metrics
Authors: James J. Jiang, Gary Klein, Richard Discenza
Venue: Journal of Systems and Software (2002)

The success of information systems (ISs) is normally defined as a composite of such performance measures as cost, time, and savings. With few systems being completed on time and within budget, application developers and users have moved to other perspectives that reflect value to organizations. Sometimes these other approaches include feedback from peers, subordinates and various other stakeholders instead of the traditional superior-subordinate performance evaluation models. Noticing the need to improve existing IS success measures for providers and users, common instruments were used to measure difference in perception over the distinct stakeholder groups of IS users and IS staff. Based on confirmatory factor analysis (CFA), the data support significant differences in perceptions between IS users and IS staff on the indicators of IS service, user satisfaction and IS staff job performance. The findings suggest efforts should be made to establish partnerships with all stakeholders to provide a more complete control process for IS development. This may include spelling out the requirements, metrics to be used, an the expectations of the deliverables and the current state of technology. Software metrics of success depend on where an individual is in the organization. Agreeing on the system success cannot occur until there is a mutual understanding of objectives and the purpose of the software.
Commutativity Analysis: A Technique for Automatically Parallelizing Pointer-Based Computations
Authors: Martin C. Rinard, Pedro C. Diniz
Venue: Proceedings of the 10th International Parallel Processing Symposium (1996)

This paper introduces an analysis technique, commutativity analysis, for automatically parallelizing computations that manipulate dynamic, pointer-based data structures. Commutativity analysis views computations as composed of operations on objects. It then analyzes the program to discover when operations commute, i.e. leave the objects in the same state regardless of the order in which they execute. If all of the operations required to perform a given computation commute, the compiler can automatically generate parallel code. Commutativity analysis eliminates many of the limitations that have prevented existing compilers, which use data dependence analysis, from successfully parallelizing pointer-based applications. It enables compilers to parallelize computations that manipulate graphs and eliminates the need to analyze the data structure construction code to extract global properties of the data structure topology. This paper shows how to use symbolic execution and expression manipulation to statically determine that operations commute and how to exploit the extracted commutativity information to generate parallel code. It also presents performance results that demonstrate that commutativity analysis can be used to successfully parallelize the Barnes-Hut hierarchical N-body solver, an important scientific application that manipulates a complex pointer-based data structure.
Robust Polyphonic Music Retrieval with N-grams
Authors: Shyamala Doraisamy, Stefan Rüger
Venue: Journal of Intelligent Information Systems (2003)

In this paper we investigate the retrieval performance of monophonic and polyphonic queries made on a polyphonic music database. We extend the n-gram approach for full-music indexing of monophonic music data to polyphonic music using both rhythm and pitch information. We define an experimental framework for a comparative and fault-tolerance study of various n-gramming strategies and encoding levels. For monophonic queries, we focus in particular on query-by-humming systems, and for polyphonic queries on query-by-example. Error models addressed in several studies are surveyed for the fault-tolerance study. Our experiments show that different n-gramming strategies and encoding precision differ widely in their effectiveness. We present the results of our study on a collection of 6366 polyphonic MIDI-encoded music pieces.
Dimensions: why do we need a new data handling architecture for sensor networks?
Authors: Deepak Ganesan, Deborah Estrin, John Heidemann
Venue: ACM SIGCOMM Computer Communication Review (2003)

An important class of networked systems is emerging that involve very large numbers of small, low-power, wireless devices. These systems offer the ability to sense the environment densely, offering unprecedented opportunities for many scientific disciplines to observe the physical world. In this paper, we argue that a data handling architecture for these devices should incorporate their extreme resource constraints - energy, storage and processing - and spatio-temporal interpretation of the physical world in the design, cost model, and metrics of evaluation. We describe DIMENSIONS, a system that provides a unified view of data handling in sensor networks, incorporating long-term storage, multi-resolution data access and spatio-temporal pattern mining.
Dealing with imprecise inputs in a fuzzy rule-based system using an implication-based rule model
Authors: Lluís Godo, Sandra Sandri
Venue: Technologies for constructing intelligent systems: Tasks (2002)

We discuss the means to efficiently propagate imprecise (but crisp) inputs in fuzzy control-like rule based systems in which fuzzy rules are chained in several levels. We consider a genuine implication-based model, in contrast to most of classical fuzzy control systems, using Rescher-Gaines implication to model the gradual relation between premises and conclusion of rules. The result of each inference is a crisp interval and we propose an efficient and sound method that provides with the tightest output intervals at one reasoning level, propagate them as input in the next level, and only pick a precise value at the very last level.
Access services in the 21st century
Authors: Merilyn Burke
Venue: Building a virtual library (2003)

Information technologies have transformed libraries in ways that most academic librarians could not have imagined twenty years ago. Traditional services, such as interlibrary loan and document delivery, have changed dramatically with the advent of technology and new telecommunications protocols. Electronic access to a myriad of databases, the proliferation of Internet sites, and patron expectations of speedy service have forced academic libraries to re-examine how they function. Higher education is no longer campus bound. Where librarians once served as the gatekeepers to information, that role is less important, as patrons now find information without the use of an intermediary.Thus, the questions for those librarians working in access services areas become those of service and resource provision. This chapter will examine interlibrary loan, electronic reserves, licenses and contracts, and the impact of distance learning on access to electronic resources and services.