ppxscal/embedding_network huggingface dataset:
A cost model for query processing in high dimensional data spaces
Authors: Christian Böhm
Venue: ACM Transactions on Database Systems (TODS) (2000)

During the last decade, multimedia databases have become increasingly important in many application areas such as medicine, CAD, geography, and molecular biology. An important research topic in multimedia databases is similarity search in large data sets. Most current approaches that address similarity search use the feature approach, which transforms important properties of the stored objects into points of a high-dimensional space (feature vectors). Thus, similarity search is transformed into a neighborhood search in feature space. Multidimensional index structures are usually applied when managing feature vectors. Query processing can be improved substantially with optimization techniques such as blocksize optimization, data space quantization, and dimension reduction. To determine optimal parameters, an accurate estimate of index-based query processing performance is crucial. In this paper we develop a cost model for index structures for point databases such as the R*-tree and the X-tree. It provides accurate estimates of the number of data page accesses for range queries and nearest-neighbor queries under a Euclidean metric and a maximum metric and a maximum metric. The problems specific to high-dimensional data spaces, called boundary effects, are considered. The concept of the fractal dimension is used to take the effects of correlated data into account.
An efficient algorithm to integrated scheduling and allocation in high-level test synthesis
Authors: T. Yang, Z. Peng
Venue: Proceedings of the conference on Design, automation and test in Europe (1998)

This paper presents a high-level test synthesis algorithm for operation scheduling and data path allocation. Contrary to other works in which scheduling and allocation are performed independently, our approach integrates these two tasks by performing them simultaneously so that the effects of scheduling and allocation on testability are exploited more effectively. The approach is based on an algorithm which applies a sequence of semantics-preserving transformations to a design to generate an efficient RT level implementation from a VHDL behavioral specification. Experimental results show the advantages of the proposed algorithm.
A proposal for input-output conventions in ALGOL 60
Authors: D. E. Knuth
Venue: Communications of the ACM (1964)

The ALGOL 60 language as first defined made no explicit reference to input and output processes. Such processes appeared to be quite dependent on the computer used, and so it was difficult to obtain agreement on those matters. As time has passed, a great many ALGOL compilers have come into use, and each compiler has incorporated some input-output facilities. Experience has shown that such facilities can be introduced in a manner which is compatible and consistent with the ALGOL language, and which (more importantly) is almost completely machine-independent. However, the existing implementations have taken many different approaches to the subject, and this has hampered the interchange of programs between installations. The ACM ALGOL committee has carefully studied the various proposals in an attempt to define a set of conventions for doing input and output which would be suitable for use on most computers. The present report constitutes the recommendations of that committee.
On the Eigenvalues of the Volume Integral Operator of Electromagnetic Scattering
Authors: Jussi Rahola
Venue: SIAM Journal on Scientific Computing (1999)

The volume integral equation of electromagnetic scattering can be used to compute the scattering by inhomogeneous or anisotropic scatterers. In this paper we compute the spectrum of the scattering integral operator for a sphere and the eigenvalues of the coefficient matrices that arise from the discretization of the integral equation. For the case of a spherical scatterer, the eigenvalues lie mostly on a line in the complex plane, with some eigenvalues lying below the line. We show how the spectrum of the integral operator can be related to the well-posedness of a modified scattering problem. The eigenvalues lying below the line segment arise from resonances in the analytical series solution of scattering by a sphere. The eigenvalues on the line are due to the branch cut of the square root in the definition of the refractive index. We try to use this information to predict the performance of iterative methods. For a normal matrix the initial guess and the eigenvalues of the coefficient matrix determine the rate of convergence of iterative solvers. We show that when the scatterer is a small sphere, the convergence rate for the nonnormal coefficient matrices can be estimated but this estimate is no longer valid for large spheres.
An efficient procedure for the generation of closed subsets
Authors: William M. Waite
Venue: Communications of the ACM (1967)

An efficient algorithm is described for generating subsets of a set S which satisfy constraints of the form: &ldquo;If si is a member of the subset, then sj must also be a member of the subset.&rdquo; The algorithm has been programmed in the WISP language and successfully run on the IBM 7094 in connection with a routine to detect feedback in multidimensional iterative networks.
Region representation: quadtrees from boundary codes
Authors: Hanan Samet
Venue: Communications of the ACM (1980)

An algorithm is presented for constructing a quadtree for a region given its boundary in the form of a chain code. Analysis of the algorithm reveals that its execution time is proportional to the product of the perimeter and the log of the diameter of the region.
Going wireless: behavior practice of new mobile phone users
Authors: Leysia Palen, Marilyn Salzman, Ed Youngs
Venue: Proceedings of the 2000 ACM conference on Computer supported cooperative work (2000)

We report on the results of a study in which 19 new mobile phone users were closely tracked for the first six weeks after service acquisition. Results show that new users tend to rapidly modify their perceptions of social appropriateness around mobile phone use, that actual nature of use frequently differs from what users initially predict, and that comprehension of service-oriented technologies can be problematic. We describe instances and features of mobile telephony practice. When in use, mobile phones occupy multiple social spaces simultaneously, spaces with norms that sometimes conflict: the physical space of the mobile phone user and the virtual space of the conversation.
Knowledge in multiagent systems: initial configurations and broadcast
Authors: Alessio R. Lomuscio, Ron van der Meyden, Mark Ryan
Venue: ACM Transactions on Computational Logic (TOCL) (2000)

The semantic framework for the modal logic of knowledge due to Halpern and Moses provides a way to ascribe knowlegde to agents in distributed and multiagent systems. In this paper we study two special cases of this framework: full systems and hypercubes. Both model static situtations in which no agents has any information about another agent's state. Full systems and hypercubes are an appropriate model for the initial configurations of many systems of interest. We establish a correspondence between full systems and hypercube systems and certain classes of Kripke frames. We show that these classes of systems correspond to the same logic. Moreover, this logic is also the same as that generated by the larger class of weakly directed frames. We provide a sound and complete axiomatization, S5WDn of this logic, and study its computational complexity. Finally, we show that under certain natural assumptions, in a model where knowledge evolves over time, S5WDn characteristics the properties of knowledge not just at the initial configuration, but also at all later configurations. In this particular, this holds for homogeneous broadcast systems, which capture settings in which agents are intially ignorant of each others local states, operate synchronously, have perfect recall, and can communicate only by broadcasting.
Detecting Salient Motion by Accumulating Directionally-Consistent Flow
Authors: L. Wixson
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2000)

Motion detection can play an important role in many vision tasks. Yet image motion can arise from ¿uninteresting¿ events as well as interesting ones. In this paper, salient motion is defined as motion that is likely to result from a typical surveillance target (e.g., a person or vehicle traveling with a sense of direction through a scene) as opposed to other distracting motions (e.g., the scintillation of specularities on water, the oscillation of vegetation in the wind). We propose an algorithm for detecting this salient motion that is based on intermediate-stage vision integration of optical flow. Empirical results are presented that illustrate the applicability of the proposed methods to real-world video. Unlike many motion detection schemes, no knowledge about expected object size or shape is necessary for rejecting the distracting motion.
The IUSR project and the common industry reporting format
Authors: Emile L. Morse
Venue: Proceedings on the 2000 conference on Universal Usability (2000)

For 3 years, the National Institute of Standards and Technology (NIST) has been leading the Industry USability Reporting (IUSR) project. The purpose of the project is to increase the visibility of software usability. Participants are from major software suppliers and customer organizations This poster presents an overview of the IUSR project. Major emphasis is placed on the Common Industry Format (CIF) for reporting the results of usability tests. The current focus of the group centers around Pilot Testing to validate the use of the CIF. Additional information about the IUSR project can be found at: iusr@nist.gov.
Incremental Design of a Data Warehouse
Authors: Dimitri Theodoratos, Timos Sellis
Venue: Journal of Intelligent Information Systems (2000)

A data warehouse (DW) can be seen as a set of materialized views defined over remote base relations. When a query is posed, it is evaluated locally, using the materialized views, without accessing the original information sources. The DWs are dynamic entities that evolve continuously over time. As time passes, new queries need to be answered by them. Some of these queries can be answered using exclusively the materialized views. In general though new views need to be added to the DW.In this paper we investigate the problem of incrementally designing a DW when new queries need to be answered and possibly extra space is allocated for view materialization. Based on an AND/OR dag representation of multiple queries, we model the problem as a state space search problem. We design incremental algorithms for selecting a set of new views to additionally materialize in the DW that: (a) fits in the extra space, (b) allows a complete rewriting of the new queries over the materialized views, and (c) minimizes the combined new query evaluation and new view maintenance cost. Finally, we discuss methods for pruning the search space so that efficiency is improved.
B-trees re-examined
Authors: Gerald Held, Michael Stonebraker
Venue: Communications of the ACM (1978)

The B-tree and its variants have, with increasing frequency, been proposed as a basic storage structure for multiuser database applications. Here, three potential problems which must be dealt with in such a structure that do not arise in more traditional static directory structures are indicated. One problem is a possible performance penalty.
H-BSP: A Hierarchical BSP Computation Model
Authors: Hojung Cha, Dongho Lee
Venue: The Journal of Supercomputing (2001)

This paper presents a new parallel computing model, called H-BSP, which adds a hierarchical concept to the BSP(Bulk Synchronous Parallel) computing model. An H-BSP program consists of a number of BSP groups which are dynamically created at run time and executed in a hierarchical fashion. H-BSP allows algorithm designers to develop more efficient algorithms by utilizing processor locality in the program. Based on the distributed memory model, H-BSP provides a group-based programming paradigm and supports Divide Conquer algorithms efficiently. This paper describes the structure of the H-BSP model, complexity analysis and some examples of H-BSP algorithm. Also presented is the performance characteristics of H-BSP algorithms based on the simulation analysis. Simulation results show that H-BSP takes advantages of processor locality and performs well in low bandwidth networks or in a constant-valence architecture such as 2-dimensional mesh. It is also proved that H-BSP can predict algorithm performance better than BSP, due to its locality-preserving nature.
An adaptive approach to indexing pervasive data
Authors: Paul Castro, Richard Muntz
Venue: Proceedings of the 2nd ACM international workshop on Data engineering for wireless and mobile access (2001)

In a pervasive computing world data will be scattered among millions of devices and finding the right data will be a fundamental problem. Several proposed service discovery architectures can assist applications searching for data within local boundaries but there is currently no support for global access to data. We introduce an application-level protocol VIA* for building self-organizing, distributed, hierarchical data indices that adapt to dynamic query workloads. These indices efficiently route queries to relevant devices and reduce the overall workload of the system. Adapting to the query workload, VIA* uses a &ldquo;query impedance&rdquo; metric to approximate the optimal hierarchy for processing the expected query workload. Distributed, &ldquo;logical&rdquo; nodes in the interior of the hierarchy collect information about query impedance and forward this information to &ldquo;data carrying&rdquo; leaf nodes that react to improve the topology of the hierarchy. We present some findings from our workload testbed that demonstrate the performance and scalability characteristics of our approach and outline our research agenda
A QoS service for low demand IP video applications over DTM
Authors: Cláudia J. Barenco, Arturo Azcorra Saloña, Joseé Ignacio Moreno
Venue: Workshop on Data communication in Latin America and the Caribbean (2001)

The differential services model (DiffServ) provides a great flexibility in defining a variety of services through PHBs (Per Hop Behaviors) and traffic conditioners. It fits in well with the integrated services model (IntServ), jointly offering features such as: QoS signaling; admission control; channel management; assignment of resources (buffer and bandwidth); sorter configuration; and establishment of traffic agreements. With this integration you can have a scalable, flexible, and dynamic QoS environment in networks of the Internet core. This article describes and analyses the DGF (DTM Guaranteed Fowarding) services that guarantees a minimum rate of retransmission of packets, based on RSVP signaling and traffic agreements (SLA), as well as losses close to the error rate of the physical medium, which are ideal features for video applications on demand.
Towards a completeness result for model checking of security protocols
Authors: Gavin Lowe
Venue: Journal of Computer Security (1999)

Model checking approaches to the analysis of security protocols have proved remarkably successful. The basic approach is to produce a model of a small system running the protocol, together with a model of the most general intruder who can interact with the protocol, and then to use a state exploration tool to search for attacks. This has led to a number of new attacks upon protocols being discovered. However, if no attack is found, this only tells us that there is no attack upon the small system we modelled semi; there may be an attack upon some larger system. This is the question we consider in this paper colon; we prove that under certain conditions on the protocol and the environment in which it operates, if there is no attack upon a particular small system (with one honest agent for each role of the protocol) leading to a breach of secrecy, then there is no attack on any larger system leading to a breach of secrecy.
Comment on multiprogramming under a page on demand strategy
Authors: J. L. Smith
Venue: Communications of the ACM (1970)

It has been brought to my attention that Figure 5 in my paper [1] is not consistent with Figure 2 in the paper [2], as it was meant to be. In the former the ordinate is defined as the incremental number of instructions executed between page demands, but the curve corresponds to the cumulative measure given in the latter.
A probabilistic algorithm to test local algebraic observability in polynomial time
Authors: Alexandre Sedoglavic
Venue: Proceedings of the 2001 international symposium on Symbolic and algebraic computation (2001)

The following questions are often encountered in system and control theory. Given an algebraic model of a physical process, which variables can be, in theory, deduced from the input-output behavior of an experiment? How many of the remaining variables should we assume to be known in order to determine all the others? These questions are parts of the local algebraic observability problem which is concerned with the existence of a non trivial Lie subalgebra of the symmetries of the model letting the inputs and the outputs invariant. We present a probabilistic seminumerical algorithm that proposes a solution to this problem in polynomial time. A bound for the necessary number of arithmetic operations on the rational field is presented. This bound is polynomial in the complexity of evaluation of the model and in the number of variables. Furthermore, we show that the size of the integers involved in the computations is polynomial in the number of variables and in the degree of the system. Last, we estimate the probability of success of our algorithm.
Register allocation via usage counts
Authors: R. A. Freiburghouse
Venue: Communications of the ACM (1974)

This paper introduces the notion of usage counts, shows how usage counts can be developed by algorithms that eliminate redundant computations, and describes how usage counts can provide the basis for register allocation. The paper compares register allocation based on usage counts to other commonly used register allocation techniques, and presents evidence which shows that the usage count technique is significantly better than these other techniques.
An intelligent distributed environment for active learning
Venue: Journal on Educational Resources in Computing (JERIC) (2001)

Active learning is an effective learning approach. In this article we present an intelligent agent-assisted environment for active learning to better support the student-centered, selfpaced, and highly interactive learning approach. The environment uses the students learningrelated profile such as learning style and background knowledge in selecting, organizing, and presenting learning material, and it adopts a new approach to course content organization and delivery based on smart instructional components that can be integrated into a wide range of courses. The environment is being implemented using the prevalent Internet, Web, digital library, and multiagent technologies.
A Cognitive Bias Approach to Feature Selection and Weighting for Case-Based Learners
Authors: Claire Cardie
Venue: Machine Learning (2000)

Research in psychology, psycholinguistics, and cognitive science has discovered and examined numerous psychological constraints on human information processing. Short term memory limitations, a focus of attention bias, and a preference for the use of temporally recent information are three examples. This paper shows that psychological constraints such as these can be used effectively as domain-independent sources of bias to guide feature set selection and weighting for case-based learning algorithms.We first show that cognitive biases can be automatically and explicitly encoded into the baseline instance representation: each bias modifies the representation by changing features, deleting features, or modifying feature weights. Next, we investigate the related problems of cognitive bias selection and cognitive bias interaction for the feature weighting approach. In particular, we compare two cross-validation algorithms for bias selection that make different assumptions about the independence of individual component biases. In evaluations on four natural language learning tasks, we show that the bias selection algorithms can determine which cognitive bias or biases are relevant for each learning task and that the accuracy of the case-based learning algorithm improves significantly when the selected bias(es) are incorporated into the baseline instance representation.
On the Use of Symbolic Analyzers in Circuit Synthesis
Authors: Rafael Cabeza, Alfonso Carlosena
Venue: Analog Integrated Circuits and Signal Processing (2000)

In this paper several examples of circuits obtained with an automatic synthesis algorithm will be shown. The algorithm, described in a companion paper [1] and outlined here for clarity, has been implemented in the Mathematica^&trade; language. We applied the new algorithm to classical problems of inmittance synthesis, obtaining well known topologies and also non-reported structures. When the algorithm is applied to challenging new problems, novel and practically useful inmittances are synthesized.
WATFOR&mdash;The University of Waterloo FORTRAN IV compiler
Authors: Peter W. Shantz, R. A. German, J. G. Mitchell, R. S. K. Shirley, C. R. Zarnke
Venue: Communications of the ACM (1967)

WATFOR is an in-core, load-and-go compiler which has been implemented within the IBM 7040/44 operating system. FORTRAN IV was selected as the source language in order to achieve maximum language compatibility with other available compiling systems, in particular the IBM 7040/44 FORTRAN IV system. The principal advantage of the WATFOR compiler is that it translates FORTRAN IV programs at speeds of up to 100 statements per second. Since the compiler resides in core there is virtually no systems overhead, and hence large batches of &ldquo;student&rdquo; programs may be processed very efficiently. The compiler also provides extensive error diagnostics, during both the compilation and the execution phases of a program run. This feature makes the system attractive to both learners and learned users alike.
Dynamic space-sharing in computer systems
Authors: L. A. Belady, C. J. Kuehner
Venue: Communications of the ACM (1969)

A formalization of relationships between space-sharing, program behavior, and processor efficiency in computer systems is presented. Concepts of value and cost of space allocation per task are defined and then value and cost are combined to develop a single parameter termed value per unit cost. The intent is to illustrate a possible analytic approach to the investigation of the problems of space-sharing and to demonstrate the method on sample problems.
Multi-terminal nets do change conventional wire length distribution models
Authors: Dirk Stoobandt
Venue: Proceedings of the 2001 international workshop on System-level interconnect prediction (2001)

Conventional models for estimating wire lengths in computer chips use Rent's rule to estimate the number of terminals between sets of gates. The number of interconnections then follows by taking into account that most nets are point-to-point connections. In this paper, we introduce a model for multi-terminal nets and we show that such nets have a fundamentally different influence on the wire length estimations than point-to-point nets. The multi-terminal net model is then used to estimate the wire length distribution in two cases: (i)m the distribution of source-sink pairs for applications of delay estimation and (ii) the distribution of Steiner tree lengths for applications related to routing resource estimation. The effects of including multi-terminal nets in the estimations are highlighted. Experiments show that the new estimated wire length distributions are close to the measured ones.