ppxscal/embedding_network huggingface dataset:
On Computer Viral Infection and the Effect of Immunization
Authors: Wang Chenxi, Knight John, Elder Matt
Venue:  (1999)

Viruses remain a significant threat to modern computer systems. Despite the best efforts of those who develop anti-virus systems, new viruses and new types of virus that are not dealt with by existing protection schemes appear regularly. In addition, the rate at which a virus can spread has risen dramatically with the increase in connectivity. Defenses against infections by known viruses rely at present on immunization yet, for a variety of reasons, immunization is often only effective on a subset of the nodes in a network and many nodes remain unprotected. Little is known about either the way in which a viral infection proceeds in general or the way that immunization affects the infection process. In this paper we present the results of a simulation study of the way in which virus infections propagate through certain types of network and of the effect that partial immunization has on the infection. The Key result is that relatively low levels of immunization can slow an infection significantly.
The Temporal Logic of Programs
Authors: A. Pnueli
Venue:  (1997)

A unified approach to program verification is suggested, which applies to both sequential and parallel programs. The main proof method suggested is that of temporal reasoning in which the time dependence of events is the basic concept. Two formal systems are presented for providing a basis for temporal reasoning. One forms a formalization of the method of intermittent assertions, while the other is an adaptation of the tense logic system K>sub<D>/sub<, and is particularly suitable for reasoning about concurrent programs. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Encode-then-encipher encryption: How to exploit nonces or redundacy in plaintexts for efficient cryptography
Authors: Mihir Bellare, Phillip Rogaway
Venue:  (2000)

We investigate the following approach to symmetric encryption: first \textit{encode\/} the message in some trivial way (eg., prepend a counter and append a checksum), and then \textit{encipher\/} the encoded message. Here ``encipher'''' means to apply a cipher (i.e.~pseudorandom permutation) $F_\key$, where~$\key$ is the shared key. We show that if the encoding step incorporates a nonce (counter or randomness), in any way at all, then the resulting encryption scheme will be semantically secure. And we show that if the encoding step incorporates redundancy, in any form at all, then, as long as the receiver verifies the presence of this redundancy in the deciphered string, the resulting encryption scheme achieves message authenticity. The second result helps explain and justify the prevalent misunderstanding that encrypting messages which have redundancy is enough to guarantee message authenticity: the statement is actually true if ``encrypting'''' is understood as ``enciphering.'''' Encode-then-encipher encryption can be used to robustly and efficiently exploit structured message spaces. If one is presented with messages known \textit{a~priori} to contain something that behaves as a nonce, then privacy can be obtained with no increase in message length, and no knowledge of the structure of the message, simply by enciphering the message. Similarly, if one is presented with messages known \textit{a~priori} to contain adequate redundancy, then message authenticity can be obtained with no increase in message length, and no knowledge of the structure of the message, simply by enciphering the message.
An adaptive invariant transform using neural network techniques
Authors: Sabine Kroner, R. Moratz, Hans Burkhardt
Venue:  (1994)

Translation invariant pattern recognition for 1D signals and 2D images can be performed using the nonlinear fast transforms of the class CsetD T. Unfortunately different backgrounds, noise or distortions of the object may strongly effect the result of the transform. However robustness and adaptivity against the mentioned distortions are desired. These properties are typical for neural nets which suggests to combine them with the class CsetD T. The RT (rapid transform) --- an element of the class CsetD T --- can be represented by a static net with simple nodes. We succeeded in realizing this signal flow graph as a neural net with coupled weights. Now the learning rule backpropagation can be applied for adapting the RT. First steps with a moving target during the learning process have been successfull with respect to the separation of different object classes.
Projected Implicit Runge-Kutta Methods for Differential-Algebraic Equations
Authors: Uri Ascher, Linda R. Petzold
Venue:  (1990)

In this paper we introduce a new class of numerical methods, Projected Implicit Runge-Kutta methods, for the solution of index-two Hessenberg systems of initial and boundary value differential-algebraic equations (DAEs). These types of systems arise in a variety of applications, including the modelling of singular optimal control problems and parameter estimation for differential-algebraic equations such as multibody systems. The new methods appear to be particularly promising for the solution of DAE boundary value problems, where the need to maintain stability in the differential part of the system often necessitates the use of methods based on symmetric discretizations. Previously defined symmetric methods have severe limitations when applied to these problems, including instability, oscillation and loss of accuracy; the new methods overcome these difficulties. For linear problems we define an essential underlying boundary value ODE and prove well-conditioning of the differential (or state-space) solution components. This is then used to prove stability and superconvergence for the corresponding numerical approximations for linear and nonlinear problems.
Fault-Tolerant Bisimulation and Process Transformations
Authors: Tomasz Janowski
Venue:  (1994)

We provide three methods of verifying concurrent systems which are tolerant of faults in their operating environment - algebraic, logical and transformational. The first is an extension of the bisimulation equivalence, the second is rooted in the Hennessy-Milner logic, and the third involves transformations of CCS processes. Based on the common semantic model of labelled transition systems, which is also used to model faults, all three methods are proved equivalent for certain classes of faults.
The Structure and Value of Modularity in Software Design
Authors: Kevin Sullivan, William G. Griswold, Yuanfang Cai, Ben Hallen
Venue:  (2001)

The concept of information hiding modularity is a cornerstone of modern software design thought, but its formulation remains casual and its emphasis on changeability is imperfectly related to the goal of creating value in a given context. We need better models of the structure and value of information hiding, for both their explanatory power and prescriptive utility. We evaluate the potential of a new theory-developed to account for the influence of modularity on the evolution of the computer industry-to inform software design. The theory uses design structure matrices to model designs and real options techniques to value them. To test the potential utility of the theory for software we represent a model software system in its terms-Parnas''s KWIC-and evaluate the results. We contribute an extension to design structure matrices and show that the options results are consistent with Parnas''s conclusions. Our results suggest that such a theory does have potential to help inform software design.
Three-Dimensional Analysis of Scoliosis Surgery Using Stereo Photogrammetry
Authors: Kellogg S. Booth, Stanley B. Jang, Chris W. Reily, Bonita J. Sawatzky
Venue:  (1995)

Scoliosis is a deformity characterized by coronal, sagittal and axial rotation of the spine. Surgical instrumentation (metal pins and rods) and eventual fusion of the spine are required in severe cases. Assessment of the deformity requires enough accuracy to allow proactive planning of individual interventions or implant designs. Conventional 2-D radiography and even 3-D CT scanning do not provide this, but our new stereophotogrammetric analysis and 3-D visualization tools do. Stereophoto pairs taken at each stage of the operation and robust statistical techniques can be used to determine rotation, translation, goodness of fit, and overall spinal contour before, during and after the surgical instrumentation. Novel features of our software include 3-D digitizing software that improves existing stereophotogrammetry methods, robust statistical methods for measuring 3-D deformity and estimating errors, full 3-D visualization of spinal deformities with optional head-coupled stereo ("fish tank virtual reality"), full integration with commercial animation software, use of consumer PhotoCD technology that significantly lowers costs for data collection and storage while increasing accuracy, and simultaneous 3-D viewing and control at remote locations over high-speed ATM networks.
Balanced Allocations (Extended abstract)
Authors: Y. Azar, A. Z. Broder, A. R. Karlin, E. Upfal
Venue:  (1995)

Suppose that we sequentially place n balls into n boxes by putting each ball into a randomly chosen box. It is well known that when we are done, the fullest box has with high probability lnn/lnlnn(1 + o(1)) balls in it. Suppose instead, that for each ball we choose two boxes at random and place the ball into the one which is less full at the time of placement. We show that with high probability, the fullest box contains only lnlnn/ln2 + O(1) balls - exponentially less than before. Furthermore, we show that a similar gap exists in the infinite process, where at each step one ball, chosen uniformly at random, is deleted, and one ball is added in the manner above. We discuss consequences of this and related theorems for dynamic resource allocation, hashing, and on-line load balancing.
The Complexity of a Two Parameter Family of Sequences
Authors: A. S. Fraenkel, T. Seeman, J. Simpson
Venue:  (2000)

We determine the complexity of the characteristic functions of a two-parameter family {A>sub<n>/sub<}>sub<n = 1>/sub<Y of infinite sequences which are associated with the winning strategies for a family of 2-player games. A special case of the family has the form A>sub<n>/sub< = enau for all n I \Bbb Z+, where a is a fixed positive irrational number. The characteristic functions of such sequences have been shown to have complexity n+1. We show that every sequence in the extended family has complexity linear in n.
The role of IT in successful knowledge management initiatives
Authors: Atreyi Kankanhalli, Fransiska Tanudidjaja, Juliana Sutanto, Bernard C. Y. Tan
Venue: Communications of the ACM (2003)

Executives must confront the challenging task of deciding the type of IT to deploy in support of their knowledge management initiatives.
A Reusable Architecture to Construct Active Database Systems
Authors: Hans Fritschi, Stella Gatziu
Venue:  (1999)

The construction system FRAMBOISE is intended to provide active database mechanisms by bundling them together out of existing, prefabricated components realizing specific active database tasks. The systems built by means of FRAMBOISE are built according to a common architecture. This reference architecture not only serves as a blueprint to assemble systems but establishes also a context that underlies the design of new components. This paper discusses the function of the reference architecture in the overall FRAMBOISE project and presents it formally by means of an architecture description language.
The Swan User''s Manual, Version 1.1
Authors: Yang Jun, Clifford A. Shaffer, Lenwood S. Heath
Venue:  (1995)

Swan is a data structure visualization program. Its main purpose is to allow the user to visualize the data structures used in a C/C++ program. Swan is specifically designed to support visualization of programs implementing various graph algorithms.
A Theory of Multi-Scale, Curvature and Torsion Based Shape Representation for Planar and Space Curves
Authors: Farzin Mokhtarian
Venue:  (1990)

This thesis presents a theory of multi-scale, curvature and torsion based shape representation for planar and space curves. The theory presented has been developed to satisfy various criteria considered useful for evaluating shape representation methods in computer vision. The criteria are: invariance, uniqueness, stability, efficiency, ease of implementation and computation of shape properties. The regular representation for planar curves is referred to as the curvature scale space image and the regular representation for space curves is referred to as the torsion scale space image. Two variants of the regular representations, referred to as the renormalized and resampled curvature and torsion scale space images, have also been proposed. A number of experiments have been carried out on the representations which show that they are very stable under severe noise conditions and very useful for tasks which call for recognition of a noisy curve of arbitrary shape at an arbitrary scale or orientation. \n Planar or space curves are described at varying levels of detail by convolving their parametric representations with Gaussian functions of varying standard deviations. The curvature or torsion of each such curve is then computed using mathematical equations which express curvature and torsion in terms of the convolutions of derivatives of Gaussian functions and parametric representations of the input curves. Curvature or torsion zero-crossing points of those curves are then located and combined to form one of the representations mentioned above. \n The process of describing a curve at increasing levels of abstraction is referred to as the evolution or arc length evolution of that curve. This thesis contains a number of theorems about evolution and arc length evolution of planar and space curves along with their proofs. Some of these theorems demonstrate that evolution and arc length evolution do not change the physical interpretation of curves as object boundaries and others are in fact statements on the global properties of planar and space curves during evolution and arc length evolution and their representations. Other theoretical results shed light on the local behavior of planar and space curves just before and just after the formation of a cusp point during evolution and arc length evolution. Together these results provide a sound theoretical foundation for the representation methods proposed in this thesis.
Independent Verification and Validation: A Missing Link in Simulation Methodology?
Authors: Arthur James D., Nance Richard E.
Venue:  (1996)

Independent verification and validation (IV&V) is a powerful tool that can be used to mitigate the increasing complexities associated with an ever-expanding set of modeling and simulation problems. In this paper we discuss the use of independent V&V within the modeling and simulation community. Literature reviews and conversations with experienced technical managers serve as a basis for our conjecture that (a) validation is the major focus of most modeling and simulation efforts, (b) verification plays only a secondary role, and (c) independent V&V is, for all practical purposes, being ignored. In an effort to raise the awareness of the benefits and applicability of independent V&V within the modeling and simulation community, we describe in a step-by-step fashion the application of independent V&V to one particular life cycle model of a simulation study.
Performance Evaluation of the Late Delta Cache Coherence Protocol
Authors: Bronis R. de Supinski, Craig Williams, Paul F. Reynolds,  Jr.
Venue:  (1996)

This paper presents the results of a simulation study designed to evaluate the performance of the late delta cache coherence protocol and a conventional directory based invalidation protocol. Delta cache protocols are a highly concurrent directory based family of coherence protocols which exploit an isotach logical time system to provide support for sequential consistency and atomicity. The late delta protocol is an update based member of this family of protocols. Our results demonstrate the efficacy of the late delta protocol across a wide range of workloads. We show that this protocol provides comparable performance to the conventional invalidation protocol under workloads with no atomicity requirements and little contention, but outperforms the conventional invalidation protocol as atomicity requirements and contention increase.
HIGH-SPEED NETWORKS AND THE INTERNET
Authors: Daniel R. Helman, Darrell D. E. Long
Venue:  (1989)

So far much of the work in advanced networks has been concentrated on high-speed transmission and the design of low-level packet switching mechanisms. Less is known about interfacing and integrating such networks into our existing data and telecommunications systems. We examine one aspect of this problem, interfacing these networks to existing LAN systems based on standard protocols. An internetworking structure is proposed, and supported with experimental evidence.
Meanings and Messages
Authors: I. D. Craig
Venue:  (1991)

The problem of meaning in DAI systems is examined in some depth. Agents in DAI systems communicate by exchanging messages, as well as by sensing and acting upon their environment, although message exchange is the focus of the current argument. The problem for such systems is that of determining the meaning of the message and acting upon it in a way that displays understanding. The current analysis centres on the grounds on which meanings can be ascribed by agents to each other. After considering the role of context and expectation, private states are examined : the conclusion that is drawn is that internal states undermine meanings and that other factors must be brought into play when deciding upon the meaning of messages and the understanding of agents.
A Model of TCP/IP Suitable for Parallel Simulation of Large Internets
Authors: Marc Abrams
Venue:  (1992)

The current Internet connects on the order of 105 hosts. What unanticipated network dynamics will arise as the Internet grows to a million or more nodes? This report describes a model of TCP/IP based on extended finite state machines intended to permit simulation on this scale. The model yields the throughput and delay averaged over all connections of a workload consisting of client and server hosts interconnected through a subnet of gateways. A variety of parameters characterize the workload, protocol software speed, subnet, and internet topology. The model presented embodies a number of conjectures on what aspects of a protocol should be omitted to permit simulation of large numbers of nodes, and conjectures on what protocol aspects should be included to give qualitative, rather than quantitative, insight into scaling the Internet.
Basic study for creating 3D model spaces from 2D digital images with photogrammetric technology
Authors: S. Tanaka, H. Furuta, E. Kitagawa, H. Noda, H. Muraki
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

Three-dimensional CAD and CG, which make use of advanced computer technology, has lately attracted considerable attention. Also attracting attention is photogrammetric technology to acquire three-dimensional coordinate data from two-dimensional image data recorded by digital cameras. Photographing and the determination of measuring points are more difficult even for experts in ground photogrammetry, for which the demand is increasing, as compared with the same tasks in aerial photogrammetry which is used for the preparation of maps and so on. Accordingly it takes enormous labor and time to obtain accurate three-dimensional coordinate data by ground photogrammetry and, therefore, it has hardly been put to practical use yet. Under the circumstances, the object of the present study was to develop a system which enables us, without requiring expensive apparatuses or expertise, to create 3D model spaces easily and quickly just by taking two-dimensional digital photographs.
An Initial Assessment of Aspect-Oriented Programming
Authors: Robert J. Walker, Elisa L. A. Baniassad, Gail C. Murphy
Venue:  (1998)

The principle of separation of concerns has long been used by software engineers to manage the complexity of software system development. Programming languages help software engineers explicitly maintain the separation of some concerns in code. As another step towards increasing the scope of concerns that can be captured cleanly within the code, Kiczales and colleagues have introduced aspect-oriented programming. In aspect-oriented programming, explicit language support is provided to help modularize design decisions that cross-cut a functionally-decomposed program. Aspect-oriented programming is intended to make it easier to reason about, develop, and maintain certain kinds of application code. To investigate these claims, we conducted two exploratory experiments that considered the impact of aspect-oriented programming, as found in AspectJ version 0.1, on two common programming activities: debugging and change. Our experimental results provide insights into the usefulness and usability of aspect-oriented programming. Our results also raise questions about the characteristics of the interface between aspects and functionally-decomposed core code that are necessary to accrue programming benefits. Most notably, the separation provided by aspect-oriented programming seems most helpful when the interface is narrow (i.e., the separation is more complete); partial separation does not necessarily provide partial benefit.
Edge Coloring Planar Graphs with Two Outerplanar Subgraphs
Authors: Lenwood S. Heath
Venue:  (1991)

The standard problem of edge coloring a graph with k colors is equivalent to partitioning the edge set of the graph into k matchings. Here edge coloring is generalized by replacing matchings with outerplanar graphs. We give a polynomial-time algorithm that edge colors any planar graph with two outerplanar subgraphs. Two is clearly minimal for the class of planar graphs. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Block Acknowledgement: Redesigning the Window Protocol
Authors: Geoffrey M. Brown, Mohamed G. Gouda, Raymond E. Miller
Venue:  (1989)

We describe a new version of the window protocol where message sequence numbers are taken from a finite domain and where both message disorder and loss can be tolerated. Most existing window protocols achieve only one of these two goals. Our protocol is based on a new method of acknowledgement, called block acknowledgement, where each acknowledgement message has two numbers m and n to acknowledge the reception of all data messages with sequence numbers ranging from m to n. Using this method of acknowledgement, the proposed protocol achieves the two goals while maintaining the same data transmission capability of the traditional window protocol.