ppxscal/embedding_network huggingface dataset:
Complexity-constrained tree-structured vector quantizers
Authors: Jean Cardinal
Venue: Signal Processing (2002)

We present a new algorithm for complexity-distortion optimization in tree-structured vector quantizers (TSVQ). The algorithm allows the user to specify the average rate and computational complexity budgets R and C, measured in bits and multiplications per sample, respectively. The output is an optimal--in a sense to be specified--TSVQ satisfying the constraints. The complexity budget is lower-bounded by the complexity of a binary TSVQ and upper-bounded by the complexity of a full-search entropy-constrained vector quantizer. Experimental results for synthetic and natural sources are given.
Agents in a Nutshell-A Very Brief Introduction
Authors: Caroline C. Hayes
Venue: IEEE Transactions on Knowledge and Data Engineering (1999)

Agent-based approaches are becoming increasingly important because of their generality, flexibility, modularity, and ability to take advantage of distributed resources. Agents are used in information retrieval, entertainment, coordinating multiple robots, and modeling economic systems. Agents can recommend music, tell stories, and interact with people. They are useful for reducing humans' work and information load in tasks such as medical monitoring and battlefield reasoning. Agents are already changing the way in which we gather information, manage investments, and conduct business. This article provides an introduction to agent issues, outlines motivations for using agent-based paradigms, and describes some of their current uses.
Two-Dimensional Pinpointing: Debugging with Normal Specifications
Authors: David Luckham, Sriram Sankar, Shuzo Takahashi
Venue: IEEE Software (1991)

Debugging techniques and tools that draw on both the high-level concepts (defined as functions) used in formal specifications and the abstraction and information-hiding constructs used in modern languages are described. The technique is based on two components. One is a novel specification language with support tools. Ada programs are specified with a language that the authors created called Anna. Their tool set is used to check the Ada program's runtime behavior for consistency with the Anna specifications. The other technique uses the tool set to find missing specifications by comparing the specification with program prototypes and to test and debug Ada programs after an accepted specification has been developed. The approach, called two-dimensional pinpointing, locates inconsistencies in software that is structured in levels.
Changing Your Endgame Strategy
Venue: IEEE Software (1990)

No abstract available
Designing High-Performance Processors Using Real Address Prediction
Authors: K. A. Hua, L. A. Liu, J. Peir
Venue: IEEE Transactions on Computers (1993)

The authors propose design techniques that may significantly simplify the cache access path, and hence offer the opportunity of shorter cycle time or fewer pipeline stages. Their proposals are based on highly accurate prediction methods that allow them to efficiently resolve address translation information early in the pipe.
Fast Computation of Normalized Edit Distances
Authors: Enrique Vidal, Andrés Marzal, Pablo Aibar
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1995)

The Normalized Edit Distance (NED) between two strings X and Y is defined as the minimum quotient between the sum of weights of the edit operations required to transform X into Y and the length of the editing path corresponding to these operations. An algorithm for computing the NED has recently been introduced by Marzal and Vidal that exhibits O(mn2) computing complexity, where m and n are the lengths of X and Y. We propose here an algorithm that is observed to require in practice the same O(mn) computing resources as the conventional unnormalized Edit Distance algorithm does. The performance of this algorithm is illustrated through computational experiments with synthetic data, as well as with real data consisting of OCR chain-coded strings.
Supporting awareness among virtual teams in a web-based collaborative system: the teamSCOPE system
Authors: Chyng Yang Jang, Charles Steinfield, Ben Pfaff
Venue: ACM SIGGROUP Bulletin (2000)

This paper overviews a Web-based collaborative system called TeamSCOPE that has been designed to support awareness needs of globally distributed teams. Four types of awareness needs of virtual teams are defined and the awareness support features of TeamSCOPE are described. The use of TeamSCOPE in a project involving a number of globally distributed engineering design teams is outlined, and evaluation results are provided. Findings illustrate how group process interacts with technology to create design challenges in the support of virtual team awareness needs.
The statistical nature of impulse noise interarrival times in digital subscriber loop systems
Authors: David D. Levey, Stephen McLaughlin
Venue: Signal Processing (2002)

The increasing demand for reliable, high-speed data transmission over the local loop utilizing xDSL technologies has prompted fresh studies into the nature and statistics of impulse noise. With a given dB margin specified on other noise (e.g. AWGN, NEXT, FEXT, etc.), impulse noise is known to be the most likely cause of error on a DSL in operation. The interarrival statistics of real impulse noise events are examined; from this examination and subsequent analysis, a Markov renewal process (MRP) model (wherein ranges of interarrival times are the Markov states) is proposed. Within this model, Poisson or Pareto probability distributions are assigned to Markov states as appropriate thereby accommodating the insights of prior studies as well as current findings. Importantly, the MRP model mirrors the clustering exhibited in real data. For events in excess of a threshold u a heavy-tailed distribution is observed. Such excesses fit a generalized Pareto distribution and are accommodated naturally within the overall MRP model as the highest Markov state.
An arithmetic theory of consistency enforcement
Authors: Sebastian Link, Klaus-Dieter Schewe
Venue: Acta Cybernetica (2002)

Consistency enforcement starts from a given program specification S and a static invariant I and aims to replace S by a slightly modified program specification SI that is provably consistent with respect to I. One formalization which suggests itself is to define SI as the greatest consistent specialization of S with respect to I, where specialization is a partial order on semantic equivalence classes of program specifications.In this paper we present such a theory on the basis of arithmetic logic. We show that with mild technical restrictions and mild restrictions concerning recursive program specifications it is possible to obtain the greatest consistent specialization gradually and independently from the order of given invariants as well as by replacing basic commands by their respective greatest consistent specialization. Furthermore, this approach allows to discuss computability and decidability aspects for the first time.
Active base stations and nodes for wireless networks
Authors: Athanassios Boulis, Paul Lettieri, Mani Srivastava
Venue: Wireless Networks (2003)

Mobile and wireless network systems are characterized by a highly time varying and heterogeneous operational environment. For example, the wireless link bandwidth and bit error rate can change due to fading, mobile nodes may have different capabilities, and in the course of its movements a mobile node may visit base stations that provide different sets of services, protocols, and interfaces. Adaptability, in various forms and at various levels of the system, is a key to combating the inherent variability of a mobile environment. This paper describes our work on Active Base Stations and Active Mobile Nodes that use the general approach of active networking to allow run-time application-specific customization of communication processing done on packets at the base station and the mobile end-nodes. This is accomplished by a software-hardware architecture that allows application specified reconfigurable hardware datapaths as well as software functions to be inserted in the path of specified packet flows at the base station and the end-node. The reconfigurable hardware datapaths as well as software functions, called Packet Processing Filters (PPF), can be uploaded or downloaded across the network, and their behavior controlled via parameter adaptation. Examples of adaptive capabilities enabled by Active Base Stations and Active Wireless Nodes include: (i) flow-specific adaptation of coding/decoding and packet lengths at the two ends of a time varying wireless link; (ii) adaptation of encryption/decryption on the wireless link according to changing locale and security environment; (iii) downloading a new or proprietary MAC protocol from a base station to visiting foreign mobiles; and (iv) dynamically uploading mobile specified services to a base station of a different service provider. We present the basic architecture and implementation approach of our system, and description of the initial software/hardware prototype.
Bit-Parallel Finite Field Multiplier and Squarer Using Polynomial Basis
Authors: Huapeng Wu
Venue: IEEE Transactions on Computers (2002)

Bit-parallel finite field multiplication using polynomial basis can be realized in two steps: polynomial multiplication and reduction modulo the irreducible polynomial. In this article, we present an upper complexity bound for the modular polynomial reduction. When the field is generated with an irreducible trinomial, closed form expressions for the coefficients of the product are derived in term of the coefficients of the multiplicands. Complexity of the multiplier architectures and their critical path length is evaluated and they are comparable to the previous proposals for the same class of fields. Analytical form for bit-parallel squaring operation is also presented. The complexities for bit-parallel squarer are also derived when an irreducible trinomial is used. Consequently, it is argued that to solve multiplicative inverse using polynomial basis can be at least as good as using normal basis.
Fault Injection Techniques and Tools
Authors: Mei-Chen Hsueh, Timothy K. Tsai, Ravishankar K. Iyer
Venue: Computer (1997)

Dependability evaluation involves the study of failures and errors. The destructive nature of a crash and long error latency make it difficult to identify the causes of failures in the operational environment. It is particularly hard to recreate a failure scenario for a large, complex system. To identify and understand potential failures, the authors use an experiment-based approach for studying system dependability. This approach is applied during the conception, design, prototype, and operational phases. To take an experiment-based approach, you must first understand a system's architecture, structure, and behavior. You need to know its tolerance for faults and failures, including its built-in detection and recovery mechanisms,and you need specific instruments and tools to inject faults, create failures or errors, and monitor their effects. Engineers most often use low-cost, simulation-based fault injection to evaluate the dependability of a system that is in the conceptual and design phases. At this point, the system under study is only a series of high-level abstractions; implementation details have yet to be determined. Thus the system is simulated on the basis of simplified assumptions. Simulation-based fault injection, which assumes that errors or failures occur according to predetermined distribution, is useful for evaluating the effectiveness of fault-tolerant mechanisms and a system's dependability; it does provide timely feedback to system engineers. However, it requires accurate input parameters, which are difficult to supply: Design and technology changes often complicate the use of past measurements. Testing a prototype, on the other hand, allows you to evaluate the system without any assumptions about system design. Instead of injecting faults, engineers can directly measure operational systems as they handle real workloads.Measurement-based analysis uses actual data, which contains much information about naturally occurring errors and failures and sometimes about recovery attempts. Although these three experimental methods have limitations, their unique values complement one another and allow for a wide spectrum of dependability studies.
A parallel iterative linear solver for solving irregular grid semiconductor device matrices
Authors: E. Tomacruz, J. Sanghavi, A. Sangiovanni-Vincentelli
Venue: Proceedings of the 1994 ACM/IEEE conference on Supercomputing (1994)

We present the use of parallel processors for the solution of drift-diffusion semiconductor device equations using an irregular grid discretization. Preconditioning, partitioning, and communication scheduling algorithms are developed to implement an efficient and robust iterative linear solver with preconditioning. The parallel program is executed on a 64 node CM-5 and is compared with PILS running on a single processor. We observe an efficiency increase in obtaining parallel speed-ups as the problem size increases. We obtain 60% efficiency for CGS with no preconditioning for large problems. Using CGS with processor ILU and magnitude threshold fill-in preconditioning for the CM-5 and CGS with ILU for PILS, we attain 50% efficiency for the solution of the large matrices.
Shared Memory Consistency Models: A Tutorial
Authors: Sarita V. Adve, Kourosh Gharachorloo
Venue: Computer (1996)

The shared memory programming model has several advantages over the message-passing model. To write correct and efficient shared memory programs, programmers need a precise notion of shared memory semantics. The memory consistency model of a shared memory multiprocessor formally specifies how the memory system will appear to the programmer. The memory consistency model is an interface between the programmer and the system, so it influences not only how parallel programs are written but virtually every aspect of parallel hardware and software design. A memory consistency model specification is required at every interface between the programmer and the system. At each level, the memory consistency model affects both programmability and performance. Furthermore, due to a lack of consensus on a single model, portability can be affected when moving software across systems supporting different models. Unfortunately, the vast literature that describes consistency models uses nonuniform, complex terminology to describe the large variety of models. This makes it difficult to understand the often subtle but important differences among models and leads to several misconceptions. This article describes memory consistency models in a way that most computer professionals can understand. The focus is consistency models proposed for hardware-based shared memory systems. Most of these models emphasize the system optimizations they support, and the authors retain this system-centric emphasis in this article.
Weighted Fuzzy Reasoning Using Weighted Fuzzy Petri Nets
Authors: S. M. Chen
Venue: IEEE Transactions on Knowledge and Data Engineering (2002)

This paper presents a Weighted Fuzzy Petri Net model (WFPN) and proposes a weighted fuzzy reasoning algorithm for rule-based systems based on Weighted Fuzzy Petri Nets. The fuzzy production rules in the knowledge base of a rule-based system are modeled by Weighted Fuzzy Petri Nets, where the truth values of the propositions appearing in the fuzzy production rules and the certainty factors of the rules are represented by fuzzy numbers. Furthermore, the weights of the propositions appearing in the rules are also represented by fuzzy numbers. The proposed weighted fuzzy reasoning algorithm can allow the rule-based systems to perform fuzzy reasoning in a more flexible and more intelligent manner.
Learning to Be Thoughtless: Social Norms and Individual Computation
Authors: Joshua M. Epstein
Venue: Computational Economics (2001)

This paper extends the literature on the evolution of norms with an agent-based model capturing a phenomenon that has been essentially ignored, namely that individual thought &ndash; or computing &ndash; is often inversely related to the strength of a social norm. Once a norm is entrenched, we conform thoughtlessly. In this model, agents learn how to behave (what norm to adopt), but &ndash; under a strategy I term Best Reply to Adaptive Sample Evidence &ndash; they also learn how much to think about how to behave. How much they are thinking affects how they behave, which &ndash; given how others behave &ndash; affects how much they think. In short, there is feedback between the social (inter-agent) and internal (intra-agent) dynamics. In addition, we generate the stylized facts regarding the spatio-temporal evolution of norms: local conformity, global diversity, and punctuated equilibria.
Efficient algorithm for transversal of disjoint convex polygons
Authors: Francis Y. L. Chin, Fu Lee Wang
Venue: Information Processing Letters (2002)

Given a set S of n disjoint convex polygons {Pi 1 ≤ i ≤ n} in a plane, each with ki vertices, the transversal problem is to determine whether there exists a straight line that goes through every polygon in S. We show that the transversal problem can be solved in O(N + n log n) time, where N = Σi=1 nki is the total number of vertices of the polygons.
Computing Global Combine Operations in the Multiport Postal Model
Authors: Amotz Bar-Noy, Jehoshua Bruck, Ching-Tien Ho, Shlomo Kipnis, Baruch Schieber
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

Consider a message-passing system of n processors, in which each processor holds one piece of data initially. The goal is to compute an associative and commutative reduction function on the n pieces of data and to make the result known to all the n processors. This operation is frequently used in many message-passing systems and is typically referred to as global combine, census computation, or gossiping. This paper explores the problem of global combine in the multiport postal model. This model is characterized by three parameters: n¿the number of processors, k¿the number of ports per processor, and ¿¿the communication latency. In this model, in every round r, each processor can send k distinct messages to k other processors, and it can receive k messages that were sent from k other processors ¿¿ 1 rounds earlier. This paper provides an optimal algorithm for the global combine problem that requires the least number of communication rounds and minimizes the time spent by any processor in sending and receiving messages.
Multiphoton imaging of neurons in living tissue: acquisition and analysis of time-lapse morphological data
Authors: Edward S. Ruthazer, Hollis T. Cline
Venue: Real-Time Imaging (2002)

Multiphoton laser scanning microscopy offers improved axial resolution over confocal microscopy for three-dimensional (3D) imaging of fluorescently labeled cells. It also greatly reduces phototoxicity and photobleaching outside the plane of focus when collecting 3D series of optical sections in living tissue. This permits images to be collected at shorter intervals with less harm to the specimen. To facilitate the transition from confocal to two-photon in vivo imaging, we have compared some of the most commonly used fluorescent vital dyes for their applicability to confocal and two-photon laser scanning microscopy. We find that many of the dyes commonly used for morphological imaging can be used for two-photon excitation microscopy. However, the optimal wavelengths for two-photon excitation cannot always be deduced from the one-photon fluorescence spectra of the fluorophores. As improvements in imaging technology are beginning to make near-real-time in vivo fluorescence imaging more feasible, flexible software that can perform temporal as well as spatial analyses of anatomical data becomes increasingly important. Here we demonstrate how we have used Object-Image, an extension of the popular public-domain NIH Image software, together with a set of custom macros for time-lapse morphometric analysis, to analyze neuronal branch growth and complexity in three dimensions over time.
Enriching the Expressive Power of Security Labels
Authors: Li Gong, Xiaolei Qian
Venue: IEEE Transactions on Knowledge and Data Engineering (1995)

Common security models such as Bell-LaPadula focus on the control of access to sensitive data but leave some important systems issues unspecified, such as the implementation of read-only objects, garbage collection, and object upgrade and downgrade paths. Consequently, different implementations of the same security model may have conflicting operational and security semantics. We propose the use of more expressive security labels for specifying these system issues within the security model, so that the semantics of a system design are precisely understood and are independent of implementation details.
An Optimal O(NlgN) Algorithm for Permutation Admissibility to Extra-Stage Cube-Type Networks
Authors: Xiaojun Shen
Venue: IEEE Transactions on Computers (1995)

A k-EMCTN is obtained by adding k more stages in front of a multistage cube-type network (MCTN). It is shown that a permutation is admissible to a k-EMCTN if and only if the conflict graph is 2k-colorable. For the case k= 1, an O(NlgN) algorithm is given for constructing the conflict graph, which leads to an O(NlgN) admissibility algorithm. Furthermore, it is shown that ¿(NlgN) bits must be checked in the binary representation of a permutation for determining its admissibility.
Simple models for articulating complex work processes
Authors: Alessandra Agostini, Giorgio De Michelis
Venue: ACM SIGGROUP Bulletin (1999)

Adaptability of workflow models can be achieved if the specification module of the Workflow Management System (WMS) is based on a theoretical kernel, allowing minimal effort for the creation of a workflow model capable of providing, when necessary, any view (and the related services) the users may want of it. The specification module of the Milano WMS has been developed on the basis of the above assumption [2, 3], so that it supports the articulation of complex work processes. Milano [1] is a system integrating in the user workspace a WMS with a multimedia conversation handler, and, finally, an object repository where an organizational handbook is stored.The workflow models of Milano constitute a small subcategory of ENS (Elementary Net Systems), namely Free-Choice Acyclic ENS. Free-choice Acyclic ENS have some nice, efficiently computable, properties: there is a synthesis algorithm from Elementary Transition Systems (ETS) to ENS so that the user can have different views of the workflow; it is possible to compute and classify the jumps recovering exceptions; morphisms between models allow an efficient correctness check for changes and support on-the-fly enactment of changes. The formal aspects of the Milano WMS are described in [2, 3]. Figure 1 presents the Workflow Net Model (WNM) (in the state {b4, b9}) of the first part of a Credit Procedure.
Pancyclicity of recursive circulant graphs
Authors: Toru Araki, Yukio Shibata
Venue: Information Processing Letters (2002)

In this paper, we study the existence of cycles of all lengths in the recursive circulant graphs, and we show a necessary and sufficient condition for the graph being pancyclic and bipancyclic.