ppxscal/embedding_network huggingface dataset:
Singular Optimal Stochastic Controls I: Existence
Authors: Ulrich G. Haussmann, Wulin Suo
Venue: SIAM Journal on Control and Optimization (1995)

We apply the compactification method to study the control problem where the state is governed by an Ito stochastic differential equation allowing both classical and singular control. The problem is reformulated as a martingale problem on an appropriate canonical space after the relaxed form of the classical control is introduced. Under some mild continuity hypotheses on the data, it is shown by purely probabilistic arguments that an optimal control for the problem exists. The value function is shown to be Borel measurable.
Fault tolerant design of multimedia servers
Authors: Steven Berson, Leana Golubchik, Richard R. Muntz
Venue: Proceedings of the 1995 ACM SIGMOD international conference on Management of data (1995)

Recent technological advances have made multimedia on-demand servers feasible. Two challenging tasks in such systems are: a) satisfying the real-time requirement for continuous delivery of objects at specified bandwidths and b) efficiently servicing multiple clients simultaneously. To accomplish these tasks and realize economies of scale associated with servicing a large user population, the multimedia server can require a large disk subsystem. Although a single disk is fairly reliable, a large disk farm can have an unacceptably high probability of disk failure. Further, due to the real-time constraint, the reliability and availability requirements of multimedia systems are very stringent. In this paper we investigate techniques for providing a high degree of reliability and availability, at low disk storage, bandwidth, and memory costs for on-demand multimedia servers.
A Generalization of a Theorem of Dehon for Simple t-Designs
Authors: Tran Van Trung
Venue: Designs, Codes and Cryptography (1996)

A generalization of a theorem of Dehon for simple t-designs is proved. Several new families of 4- and 5-designs having certain additional property regarding their block intersection numbers are obtained by applying this result.
A picture-based object-oriented visual simulation environment
Authors: Osman Balci, Anders I. Bertelrud, Charles M. Esterbrook, Richard E. Nance
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The paper introduces the Visual Simulation Environment (VSE)-a new technology in visual simulation created as a result of experimental research for over a decade. Computer-aided support throughout the entire model development life cycle is required to manage the ever-increasing complexity of (visual) simulation modeling. Ongoing research since 1983 has sought to provide such support in the form of a computer-aided simulation model development environment. Based on the experience gained from two major prototype environments, the production version has been under development since August 1992. The current status of the VSE is presented.
Perspectives on ATM switch architecture and the influence of traffic pattern assumptions on switch design
Authors: Robert J. Simcoe, Tong-Bi Pei
Venue: ACM SIGCOMM Computer Communication Review (1995)

Switch designs and the uniform distribution traffic pattern that has been the basis of much switch design analysis are discussed. In particular it is shown that head of line blocking is not the major cause of switch and link underutilization. Switch fabric and buffer system input bandwidth tradeoffs are described. For client server applications it is shown that having the majority of switch buffers on the input side of a switch reduces overall switch buffering.
Application of ADI Iterative Methods to the Restoration of Noisy Images
Authors: D. Calvetti, L. Reichel
Venue: SIAM Journal on Matrix Analysis and Applications (1996)

The restoration of two-dimensional images in the presence of noise by Wiener's minimum mean square error filter requires the solution of large linear systems of equations. When the noise is white and Gaussian, and under suitable assumptions on the image, these equations can be written as a Sylvester's equation \[ T_1^{-1}\hat{F}+\hat{F}T_2=C \] for the matrix $\hat{F}$ representing the restored image. The matrices $T_1$ and $T_2$ are symmetric positive definite Toeplitz matrices. We show that the ADI iterative method is well suited for the solution of these Sylvester's equations, and illustrate this with computed examples for the case when the image is described by a separable first-order Markov process. We also consider generalizations of the ADI iterative method, propose new algorithms for the generation of iteration parameters, and illustrate the competitiveness of these schemes.
Development of oriented ocular dominance bands as a consequence of areal geometry
Authors: H.-U. Bauer
Venue: Neural Computation (1995)

It has been hypothesized that the different appearance of ocular dominance bands in the cat and the monkey is a consequence of the different mapping geometries in these species (LeVay et al. 1985; Anderson et al. 1988). Here I investigate the impact of areal geometries on the preferred direction of ocular dominance bands in two adaptive map formation models, the self-organizing feature map and the elastic net algorithm. In the case of the self-organizing feature map, the occurrence of instabilities that correspond to ocular dominance bands can be analytically investigated. The instabilities automatically yield stripes of correct orientation. These analytic results are complemented by simulations. In the case of the elastic net algorithm, simulations reveal two different parameter regimes of the algorithm, only one of which leads to stripes of correct orientation. The results suggest that neighborhood preservation in visual maps is enforced in the backward direction, such that neighboring cells in the cortex have neighboring receptive fields, and not vice versa.
A survey of UNI signaling systems and protocols for ATM networks
Authors: Burkhard Stiller
Venue: ACM SIGCOMM Computer Communication Review (1995)

The main aspect covered by signaling systems and protocols for ATM networks concerns the possibility to manage, maintain, and control a user-driven communication between arbitrary ATM end-systems connected to an ATM network. The tasks and procedures defined for, e.g., setting-up an ATM connection, are often very different concerning the rrelevant specifications of various working bodies (such as ITU-T or ATM-Forum) or certain vendors, although the basis to be done for maintaining ATM connections are always principally the same. The reason for this situation is, that the intentions of working bodies are different and each one of them follows specific strategies for certain scenarios (such as for point-to-point unicast or point-to-multipoint multicast). Nevertheless, various types of characteristics (such as addressing, multicast, or interworking) are requested from applications residing on top of ATM networks.Therefore, this survey of signaling systems and protocols for ATM networks identifies for several of selected approaches (such as Q.2931, UNI 3.1, or CMAP) important characteristics and relevant scenarios. Furthermore, a table-based comparison of some approaches has been added
Blue&mdash;a language for teaching object-oriented programming
Authors: Michael Kölling, John Rosenberg
Venue: ACM SIGCSE Bulletin (1996)

Teaching object-oriented programming has clearly become an important part of computer science education. We agree with many others that the best place to teach it is in the CS1 introductory course. Many problems with this have been reported in the literature. These mainly result from inadequate languages and environments. Blue is a new language and integrated programming environment, currently under development explicitly for object-oriented teaching. We expect clear advantages from the use of Blue for first year teaching compared to using other available languages. This paper describes the design principles on which the language was based and the most important aspects of the language itself.
The S/Net's Linda kernel
Authors: Nicholas Carriero, David Gelernter
Venue: ACM Transactions on Computer Systems (TOCS) (1986)

Linda is a parallel programming language that differs from other parallel languages in its simplicity and in its support for distributed data structures. The S/Net is a multicomputer, designed and built at AT&T Bell Laboratories, that is based on a fast, word-parallel bus interconnect. We describe the Linda-supporting communication kernel we have implemented on the S/Net. The implementation suggests that Linda's unusual shared-memory-like communication primitives can be made to run well in the absence of physically shared memory; the simplicity of the language and of our implementation's logical structure suggest that similar Linda implementations might readily be constructed on related architectures. We outline the language, and programming methodologies based on distributed data structures; we then describe the implementation, and the performance both of the Linda primitives themselves and of a simple S/Net-Linda matrix-multiplication program designed to exercise them.
Succeeding as a clandestine change agent
Authors: C. Dennis Allen
Venue: Communications of the ACM (1995)

Changing the attitudes and work habits of a large organization is daunting at best. The task is more challenging when the organization perceives itself as eminently successful, dominating the market in its category. During the past 5 years I've seen the evolution of the product design processes as I moved from user-interface (UI) designer, to manager of a large UI design group, to my current position as a product design strategist.
A test problem generator for large-scale unconstrained optimization
Authors: R. S. Dembo, T. Steihaug
Venue: ACM Transactions on Mathematical Software (TOMS) (1985)

A test problem generator for large-scale unconstrained optimization is described. It permits the generation of a poorly or well-conditioned problems of arbitrary size, derived from nonlinear network flow models. An eigenvalue analysis provides bounds on the condition number of the Hessian of the objective function and an example of an efficient preconditioner, using these bounds, is outlined.
The mythical man-month (anniversary ed.)
Authors: Frederick P. Brooks,  Jr.
Venue:  (1995)

Few books on software project management have been as influential and timeless as The Mythical Man-Month. With a blend of software engineering facts and thought-provoking opinions, Fred Brooks offers insight for anyone managing complex projects. These essays draw from his experience as project manager for the IBM System/360 computer family and then for OS/360, its massive software system. Now, 20 years after the initial publication of his book, Brooks has revisited his original ideas and added new thoughts and advice, both for readers already familiar with his work and for readers discovering it for the first time.The added chapters contain (1) a crisp condensation of all the propositions asserted in the original book, including Brooks' central argument in The Mythical Man-Month: that large programming projects suffer management problems different from small ones due to the division of labor; that the conceptual integrity of the product is therefore critical; and that it is difficult but possible to achieve this unity; (2) Brooks' view of these propositions a generation later; (3) a reprint of his classic 1986 paper "No Silver Bullet"; and (4) today's thoughts on the 1986 assertion, "There will be no silver bullet within ten years." 0201835959B04262002
Multicast routing in internetworks and extended LANs
Authors: Stephen E. Deering
Venue: ACM SIGCOMM Computer Communication Review (1995)

Multicasting is used within local-area networks to make distributed applications more robust and more efficient. The growing need to distribute applications across multiple, interconnected networks, and the increasing availability of high-performance, high-capacity switching nodes and networks, lead us to consider providing LAN-style multicasting across an internetwork. In this paper, we propose extensions to two common internetwork routing algorithms---distance-vector routing and link-state routing---to support low-delay datagram multicasting. We also suggest modifications to the single-spanning-tree routing algorithm, commonly used by link-layer bridges, to reduce the costs of multicasting in large extended LANs. Finally, we show how different link-layer and network-layer multicast routing algorithms can be combined hierarchically to support multicasting across large, heterogeneous internetworks.
Arithmetic coding for data compression
Authors: Ian H. Witten, Radford M. Neal, John G. Cleary
Venue: Communications of the ACM (1987)

The state of the art in data compression is arithmetic coding, not the better-known Huffman method. Arithmetic coding gives greater compression, is faster for adaptive models, and clearly separates the model from the channel encoding.
A report on the Durham program transformations workshop
Authors: Tim Bull, Keith Bennett
Venue: ACM SIGSOFT Software Engineering Notes (1996)

A Workshop on Program Transformation Systems was held in the Centre for Software Maintenance at University of Durham on 1st and 2nd April 1996.The Workshop was intended as a follow up for the successful event held on the same topic at ICSE in Seattle in 1995. Twenty-three people attended the Workshop, and this is a short report on the proceedings.
Secure communications in ATM networks
Authors: Daniel Stevenson, Nathan Hillery, Greg Byrd
Venue: Communications of the ACM (1995)

High-speed networking technology and standards have progressed dramatically in the past few years and much attention is now focused on deployment efforts, such as the North Carolina Information Highway (NCIH) [7], and applications. With this shift in emphasis, concerns have been raised about information security. Examples of abuse of the Internet abound and unfortunately ATM networks are subject to many of these same abuses. This is of subtanstial concern when thinking about extending the reach of public data networking to broad segments of society.
A Real-Time Matching System for Large Fingerprint Databases
Authors: Nalini K. Ratha, Kalle Karu, Shaoyun Chen, Anil K. Jain
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

With the current rapid growth in multimedia technology, there is an imminent need for efficient techniques to search and query large image databases. Because of their unique and peculiar needs, image databases cannot be treated in a similar fashion to other types of digital libraries. The contextual dependencies present in images, and the complex nature of two-dimensional image data make the representation issues more difficult for image databases. An invariant representation of an image is still an open research issue. For these reasons, it is difficult to find a universal content-based retrieval technique. Current approaches based on shape, texture, and color for indexing image databases have met with limited success. Further, these techniques have not been adequately tested in the presence of noise and distortions. A given application domain offers stronger constraints for improving the retrieval performance. Fingerprint databases are characterized by their large size as well as noisy and distorted query images. Distortions are very common in fingerprint images due to elasticity of the skin. In this paper, a method of indexing large fingerprint image databases is presented. The approach integrates a number of domain-specific high-level features such as pattern class and ridge density at higher levels of the search. At the lowest level, it incorporates elastic structural feature-based matching for indexing the database. With a multilevel indexing approach, we have been able to reduce the search space. The search engine has also been implemented on Splash 2¿a field programmable gate array (FPGA)-based array processor to obtain near-ASIC level speed of matching. Our approach has been tested on a locally collected test data and on NIST-9, a large fingerprint database available in the public domain.
Developing industrial strength simulation models
Authors: Marvin S. Seppanen
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The paper is based on over 25 years of experience in the field of discrete event simulation. Over this time span there has been dramatic increases in computer power, the number and the capabilities of simulation languages, and the total number of people using computers in their daily work. However, these changes have yet to make discrete event simulation a standard manufacturing decision support tool. The paper explores some reasons for this short-fall and offers some near-term and long-term solutions.
Tree Spanners
Authors: Leizhen Cai, Derek G. Corneil
Venue: SIAM Journal on Discrete Mathematics (1995)

A tree $t$-spanner $T$ of a graph $G$ is a spanning tree in which the distance between every pair of vertices is at most $t$ times their distance in $G$. This notion is motivated by applications in communication networks, distributed systems, and network design. This paper studies graph-theoretic, algorithmic, and complexity issues about tree spanners. It is shown that a tree 1-spanner, if it exists, in a weighted graph with $m$ edges and $n$ vertices is a minimum spanning tree and can be found in $O(m \log \beta(m, n))$ time, where $\beta(m, n) = \min\{i\mid\log^{(i)}n \leq m/n\}$. On the other hand, for any fixed $t > 1$, the problem of determining the existence of a tree $t$-spanner in a weighted graph is proven to be NP-complete. For unweighted graphs, it is shown that constructing a tree 2-spanner takes linear time, whereas determining the existence of a tree $t$-spanner is NP-complete for any fixed $t \geq 4$. A theorem that captures the structure of tree 2-spanners is presented for unweighted graphs. For digraphs, an $O((m + n)\alpha(m, n))$ algorithm is provided for finding a tree $t$-spanner with $t$ as small as possible, where $\alpha(m, n)$ is a functional inverse of Ackerman's function. The results for tree spanners on undirected graphs are extended to "quasi-tree spanners" on digraphs. Furthermore, linear-time algorithms are derived for verifying tree spanners and quasi-tree spanners.
The building blocks for specifying communication behavior of complex objects: an activity-driven approach
Authors: Ling Liu, Robert Meersman
Venue: ACM Transactions on Database Systems (TODS) (1996)

Communication behavior represents dynamic evolution and cooperation of a group of objects in accomplishing a task. It is an important feature in object-oriented systems. We propose the concept of activity as a basic building block for declarative specification of communication behavior in object-oriented database systems, including the temporal ordering of message exchanges within object communication and the behavioral relationships between activity executions. We formally introduce two kinds of activity composition mechanisms: activity specialization and activity aggregation for abstract implementation of communication behavior. The former is suited for behavioral refinement of existing activities into specialized activities. The latter is used for behavioral composition of simpler activities into complex activities, and ultimately, into the envisaged database system. We use first-order temporal logic as an underlying formalism for specification of communication constraints. The well known Air-traffic-control case is used as a running example to highlight the underlying concepts, to illustrate the usefulness, and to assess the effectiveness of the activity model for declarative specification of communication behavior in the relevant universe of discourse. We also propose a methodological framework for integrating activity schema with entity schema in an object-oriented design environment.
Iteration abstraction in Sather
Authors: Stephan Murer, Stephen Omohundro, David Stoutamire, Clemens Szyperski
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1996)

Sather extends the notion of an iterator in a powerful new way. We argue that iteration abstractions belong in class interfaces on an equal footing with routines. Sather iterators were derived from CLU iterators but are much more flexible and better suited for object-oriented programming. We retain the property that iterators are structured, i.e., strictly bound to a controlling structured statement. We motivate and describe the construct along with several simple examples. We compare it with iteration based on CLU iterators, cursors, riders, streams, series, generators, coroutines, blocks, closures, and lambda expressions. Finally, we describe experiences with iterators in the Sather compiler and libraries.
Striping in a RAID level 5 disk array
Authors: Peter M. Chen, Edward K. Lee
Venue: Proceedings of the 1995 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems (1995)

Redundant disk arrays are an increasingly popular way to improve I/O system performance. Past research has studied how to stripe data in non-redundant (RAID Level 0) disk arrays, but none has yet been done on how to stripe data in redundant disk arrays such as RAID Level 5, or on how the choice of striping unit varies with the number of disks. Using synthetic workloads, we derive simple design rules for striping data in RAID Level 5 disk arrays given varying amounts of workload information. We then validate the synthetically derived design rules using real workload traces to show that the design rules apply well to real systems.We find no difference in the optimal striping units for RAID Level 0 and 5 for read-intensive workloads. For write-intensive workloads, in contrast, the overhead of maintaining parity causes full-stripe writes (writes that span the entire error-correction group) to be more efficient than read-modify writes or reconstruct writes. This additional factor causes the optimal striping unit for RAID Level 5 to be four times smaller for write-intensive workloads than for read-intensive workloads.We next investigate how the optimal striping unit varies with the number of disks in an array. We find that the optimal striping unit for reads in a RAID Level 5 varies inversely to the number of disks, but that the optimal striping unit for writes varies with the number of disks. Overall, we find that the optimal striping unit for workloads with an unspecified mix of reads and writes is independent of the number of disks.Together, these trends lead us to recommend (in the absence of specific workload information) that the striping unit over a wide range of RAID Level 5 disk array sizes be equal to 1/2 * average positioning time * disk transfer rate.