ppxscal/embedding_network huggingface dataset:
Constraint analysis for code generation: basic techniques and applications in FACTS
Authors: Koen Van Eijk, Bart Mesman, Carlos A. Alba Pinto, Qin Zhao, Marco Bekooij, Jef Van Meerbergen, Jochen Jess
Venue: ACM Transactions on Design Automation of Electronic Systems (TODAES) (2000)

Code generation methods for digital signal processors are increasingly hampered by the combination of tight timing constraints imposed by signal p processing applications and resource constraints implied by the processor architecture. In particular, limited resource availability (e.g.registers) poses a problem for traditional methods that perform code generation in separate stages (e.g., scheduling followed by register binding). This separation often results in suboptimality (or even infeasibility) of the generated solutions because it ignores the problem of phase coupling (e.g., since value lifetimes are a result of scheduling, scheduling affects the solution space for register binding). As a result, traditional methods need an increasing amount of help from the programmer (or designer) to arrive at a feasible solution. Because this requires an excessive amount of design time and extensive knowledge of the processor architecture, there is a need for automated techniques that can cope with the different kinds of contraints during scheduling. By exploiting these constraints to prune the schedule search space, the scheduler is often prevented from making a decision that inevitably violates one or more constraints. FACTS is a research tool developed for this purpose. In this paper we will elucidate the philosophy and concepts of FACTS and demonstrate them on a number of examples.
A method of syntax-checking ALGOL 60
Authors: Marjorie P. Lietzke
Venue: Communications of the ACM (1964)

A syntax checker was designed based on the syntax of ALGOL as described in the ALGOL 60 Report [Communications of the ACM, May 1960]. Since the definition of the elements of the language is recursive it seemed most desirable to design the syntax checker as a set of mutually recursive processors tied together by subroutines which perform certain bookkeeping functions. Because of the recursive nature of the language and of the syntax checker the problem of recovery after an error required much attention. A method was devised which permits most programs to be checked completely despite errors.
Taking advantage of design patterns in GIS domain (poster session)
Authors: L. Polasek, Arturo Zambrano, S. Gordillo, J. Bazocco, G. Trilla, D. Cano, A. Literas
Venue: Addendum to the 2000 proceedings of the conference on Object-oriented programming, systems, languages, and applications (Addendum) (2000)

Geographic Information Systems (GIS) are used to collect, store, analyze and present information describing physical and logical aspects of real world entities. They deal with several areas, such as georeferencing, topology, visualization, representation of continuous information and so on. Most of GIS applications are hardly adapted to new requirements, like changing of the reference system, integrating vector and raster models, or handling continuous information, among others. This work presents an pattern driven architecture for building GIS applications. The result is a framework that is focused on flexibility and adaptability features.
List tracing in systems allowing multiple cell-types
Authors: Robert R. Fenichel
Venue: Communications of the ACM (1971)

List-processing systems have each allowed the use of only a single size and configuration of list cell. In this paper a system is described which allows the use of arbitrarily many different sizes and configurations of list cells, possibly not specified until run time.
Performance Evaluation of Storage Systems Based on Network-Attached Disks
Authors: Gang Ma, Adnan Khaleel, A. L. Narasimha Reddy
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

The emergence of network-attached disks provides the possibility of transferring data between the storage system and the client directly. This offers new possibilities in building a distributed storage system. In this paper, we examine different storage organizations based on network-attached disks and compare the performance of these systems to a traditional system. Trace-driven simulations are used to measure the average response times of the client requests in two different workloads. We show that the advantages of distributing the server's network processing load to disks can be offset by losses in cache hits in a system based on network-attached disks. The two workloads we considered highlight this impact. We show that it is possible to offload significant load from the server by utilizing network-attached disks and point out that specific applications may be able to better exploit the features of network-attached disks.
A imaginary number system
Authors: Donald E. Knuth
Venue: Communications of the ACM (1960)

For centuries the decimal number system reigned supreme, except, perhaps, among the Mayan Indians, until the advent of digital computers brought the binary and octal systems into the limelight. This paper introduces another number system which may prove useful for manipulating complex numbers on machines.
Safety critical systems based on formal models
Authors: Lars Asplund, Kristina Lundqvist
Venue: ACM SIGAda Ada Letters (2000)

The Ravenscar profile for high integrity systems using Ada 95 is well defined in all real-time aspects. The complexity of the run-time system has been reduced to allow full utilization of formal methods for applications using the Ravenscar profile. In the Mana project a tool set is being developed including a formal model of a Ravenscar compliant run-time system, a gnat compatible run-time system, and an ASIS based tool to allow for the verification of a system including both COTS and code that is reused.
An abstract programming model
Authors: Christopher E. Rothe
Venue: Communications of the ACM (1981)

An abstract model of a processor is presented informally. The model can be used by itself to abstractly describe algorithms, or with a direct implementation to write and run programs, or as the foundation of a programming language. In the last case, a translator allows higher level descriptions of algorithms for the model.
The Use of Proof in Diversity Arguments
Authors: Bev Littlewood
Venue: IEEE Transactions on Software Engineering (2000)

The limits to the reliability that can be claimed for a design-diverse fault-tolerant system are mainly determined by the dependence that must be expected in the failure behaviours of the different versions: claims for independence between version failure processes are not believable. In this note we examine a different approach, in which a simple secondary system is used as a back-up to a more complex primary. The secondary system is sufficiently simple that claims for its perfection (with respect to design faults) are possible, but there is not complete certainty about such perfection. It is shown that assessment of the reliability of the overall fault-tolerant system in this case may take advantage of claims for independence that are more plausible than those involved in design diversity.
A program to reduce the number of open I/T jobs at Purdue University: an industry case study
Authors: Julie R. Mariga
Venue: Proceedings of the 2001 ACM SIGCPR conference on Computer personnel research (2001)

The number of unfilled information technology (IT) positions in demand in the United States is estimated at 1.6 million this year. The demand for skilled IT people far exceeds the supply and it is estimated that half of the 1.6 million positions will likely remain vacant. Due to the shortage of skilled I/T professionals, companies and universities have to be creative and develop in-house programs that will allow them to produce their own IT professionals from among a pool of employees working in non-technical areas or possessing non-technical degrees. Purdue University has developed such a program that will help fill open computing positions by providing people with a solid educational foundation as well as current technical skills. This paper discusses the program Purdue has put into place to help overcome its shortage of qualified I/T professionals.
A moment of perfect clarity I: the parallel census technique
Authors: Lane A. Hemaspaandra, Christian Glaßer
Venue: ACM SIGACT News (2000)

We discuss the history and uses of the parallel census technique---an elegant tool in the study of certain computational objects having polynomially bounded census functions. A sequel [GH] will discuss advances (including [CNS95] and Gla szlig;er [Gla00]), some related to the parallel census technique and some due to other approaches, in the complexity-class collapses that follow if NP has sparse hard sets under reductions weaker than (full) truth-table reductions.
ARVIKA: augmented reality for development, production and service
Authors: Wolfgang Wohlgemuth, Gunthard Triebfürst
Venue: Proceedings of DARE 2000 on Designing augmented reality environments (2000)

The project ARVIKA, sponsored by the BMBF (ministry of education and research) and supervised by the DLR (German Aerospace Center), uses augmented reality (AR) technologies to research and create a user-oriented and system-driven support of operation procedures. It focuses on the development, production, and service of complex technical products and systems. This article aims to give an survey of the project ARVIKA. The realisation of the particular AR-applications results from the partners specified at the end of this article.
When policies are better than plans: decision-theoretic planning of recommendation sequences
Authors: Thorsten Bohnenberger, Anthony Jameson
Venue: Proceedings of the 6th international conference on Intelligent user interfaces (2001)

An intelligent user interface sometimes needs to present a sequence of related recommendations to a user, in spite of being uncertain in advance as to whether (and with what success) the user will follow each recommendation. There are potential advantages to the use of decision-theoretic planning methods which yield an optimal policyfor the situation-dependent presentation of recommendations. This approach is discussed with reference to an example involving route instructions given by an airport assistance system.
Library support for orthogonal processor groups
Authors: Thomas Rauber, Robert Reilein, Gudula Rünger
Venue: Proceedings of the thirteenth annual ACM symposium on Parallel algorithms and architectures (2001)

Many implementations on message-passing machines can benefit from an exploitation of mixed task and data parallelism. A suitable parallel programming model is a group-SPMD model which requires a structuring of the processors in to subsets and a partition of the program into multi-processor tasks. In this paper, we introduce a library support for the specification of message-passing programs in a group-SPMD style allowing different partitions in a single program. We describe the implementation of the library functions and illustrate the programming style.
Sets and constraint logic programming
Authors: Agostino Dovier, Carla Piazza, Enrico Pontelli, Gianfranco Rossi
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (2000)

In this paper we present a study of the problem of handling constraints made by conjunctions of positive and negative literals based on the predicate symbols =, &isin;,&cup; and &dvbm0; (i.e., disjointness of two sets) in a (hybrid) universe of finite sets. We also review and compare the main techniques considered to represent finite sets in the context of logic languages. The resulting contraint algorithms are embedded in a Constraint Logic Programming (CLP) language which provides finite sets&mdash;along with basic set-theoretic operations&mdash;as first-class objects of the language. The language&mdash;called CLP( SET )&mdash;is an instance of the general CLP framework, and as such it inherits all the general features and theoretical results of this scheme. We provide, through programming examples, a taste of the expressive power offered by programming in CLP(SET .
Numerical Analysis: A fast fourier transform algorithm for real-valued series
Authors: Glenn D. Bergland
Venue: Communications of the ACM (1968)

A new procedure is presented for calculating the complex, discrete Fourier transform of real-valued time series. This procedure is described for an example where the number of points in the series is an integral power of two. This algorithm preserves the order and symmetry of the Cooley-Tukey fast Fourier transform algorithm while effecting the two-to-one reduction in computation and storage which can be achieved when the series is real. Also discussed are hardware and software implementations of the algorithm which perform only (N/4) log2 (N/2) complex multiply and add operations, and which require only N real storage locations in analyzing each N-point record.
Design of Fault-Tolerant Large-Scale VOD Servers: With Emphasis on High-Performance and Low-Cost
Authors: Leana Golubchik, Richard R. Muntz, Cheng-Fu Chou, Steven Berson
Venue: IEEE Transactions on Parallel and Distributed Systems (2001)

Recent technological advances in digital signal processing, data compression techniques, and high-speed communication networks have made Video-on-Demand (VOD) servers feasible. A challenging task in such systems is servicing multiple clients simultaneously while satisfying real-time requirements of continuous delivery of objects at specified rates. To accomplish these tasks and realize economies of scale associated with servicing a large user population, a VOD server requires a large disk subsystem. Although a single disk is fairly reliable, a large disk farm can have an unacceptably high probability of disk failure. Furthermore, due to real-time constraints, the reliability requirements of VOD systems are even more stringent than those of traditional information systems. Traditional RAID solutions are inadequate due to poor resource usage. Thus, in this paper, we present alternative schemes which provide a high degree of reliability at low disk storage, bandwidth, and memory costs for on-demand multimedia servers. Moreover, we discuss some of the main issues and trade-offs associated with providing fault tolerance in multidisk VOD systems. We would like to impress upon the reader that one of the main points of this paper is the exposition of trade-offs and issues associated with designing fault-tolerant VOD servers. It is not the case that one fault tolerance scheme is absolutely better than another, but rather that one must understand the trade-offs as well as one's system constraints and then choose a fault tolerance scheme accordingly.
A digital television navigator
Authors: Chengyuan Peng, Petri Vuorimaa
Venue: Proceedings of the eighth ACM international conference on Multimedia (2000)

Digital television is a new, interesting, and rich platform for developing next generation multimedia services. One of the key digital television standards is Multimedia Home Platform (MHP) which includes hardware devices and software architecture. Navigator is the most important multimedia service of digital television. It acts the main index of all the services available in set-top box. In this paper we presented a Java Navigator developed in Future TV project.
Evaluating strategies and systems for content based indexing of person images on the Web
Authors: Yuksel Alp Aslandogan, Clement T. Yu
Venue: Proceedings of the eighth ACM international conference on Multimedia (2000)

Content based indexing of multimedia has always been a challenging task. The enormity and the diversity of the multimedia content on the web adds another dimension to this challenge. In this paper, we examine ways of combining visual and textual information for content based indexing of multimedia on the web. In particular, we examine different methods of combining evidences due to face detection, Text/HTML analysis and face recognition for identifying person images. We provide experimental evaluation of the following strategies: i) Face detection on the image followed by Text/HTML analysis of the containing page; ii) face detection followed by face recognition; iii) face detection followed by a linear combination of evidences due to text/HTML analysis and face recognition; and iv) face detection followed by a Dempster-Shafer combination of evidences due to text/HTML analysis and face recognition. These strategies were implemented in an automatic web search agent named Diogenes1 and compared against some well known web image search engines. The latter includes commercial systems such as Alta Vista, Lycos and Ditto, and a research prototype, WebSEEk. We report the results of our experimental retrievals where Diogenes outperformed these search engines for celebrity image queries in terms of average precision.
Typing a multi-language intermediate code
Authors: Andrew D. Gordon, Don Syme
Venue: ACM SIGPLAN Notices (2001)

The Microsoft .NET Framework is a new computing architecture designed to support a variety of distributed applications and web-based services. .NET software components are typically distributed in an object-oriented intermediate language, Microsoft IL, executed by the Microsoft Common Language Runtime. To allow convenient multi-language working, IL supports a wide variety of high-level language constructs, including class-based objects, inheritance, garbage collection, and a security mechanism based on type safe execution.This paper precisely describes the type system for a substantial fragment of IL that includes several novel features: certain objects may be allocated either on the heap or on the stack; those on the stack may be boxed onto the heap, and those on the heap may be unboxed onto the stack; methods may receive arguments and return results via typed pointers, which can reference both the stack and the heap, including the interiors of objects on the heap. We present a formal semantics for the fragment. Our typing rules determine well-typed IL instruction sequences that can be assembled and executed. Of particular interest are rules to ensure no pointer into the stack outlives its target. Our main theorem asserts type safety, that well-typed programs in our IL fragment do not lead to untrapped execution errors.Our main theorem does not directly apply to the product. Still, the formal system of this paper is an abstraction of informal and executable specifications we wrote for the full product during its development. Our informal specification became the basis of the product team's working specification of type-checking. The process of writing this specification, deploying the executable specification as a test oracle, and applying theorem proving techniques, helped us identify several security critical bugs during development.
A new predictive flow control scheme for efficient network utilization and QoS
Authors: Dongyu Qiu, Ness B. Shroff
Venue: Proceedings of the 2001 ACM SIGMETRICS international conference on Measurement and modeling of computer systems (2001)

In this paper we develop a new predictive flow control scheme and analyze its performance. This scheme controls the non-real-time traffic based on predicting the real-time traffic. The goal of the work is to operate the network in a low congestion, high throughput regime. We provide a rigorous analysis of the performance of our flow control method and show that the algorithm has attractive and useful properties. From our analysis we obtain an explicit condition that gives us design guidelines on how to choose a predictor. We learn that it is especially important to take the queueing effect into account in developing the predictor. We also provide numerical results comparing different predictors that use varying degrees of information from the network.
New methods to color the vertices of a graph
Authors: Daniel Brélaz
Venue: Communications of the ACM (1979)

This paper describes efficient new heuristic methods to color the vertices of a graph which rely upon the comparison of the degrees and structure of a graph. A method is developed which is exact for bipartite graphs and is an important part of heuristic procedures to find maximal cliques in general graphs. Finally an exact method is given which performs better than the Randall-Brown algorithm and is able to color larger graphs, and the new heuristic methods, the classical methods, and the exact method are compared.
Hybrid Run-time Power Management Technique for Real-time Embedded System with Voltage Scalable Processor
Authors: Minyoung Kim, Soonhoi Ha
Venue: ACM SIGPLAN Notices (2001)

This paper presents a new run-time power management technique for real-time embedded systems which consist of a voltage scalable processor and power controllable peripheral devices. We have observed that there exist significant trade-offs in terms of energy consumption between the Dynamic Power Management (DPM) scheme and the Dynamic Voltage Scaling (DVS) scheme over a wide range of system operating conditions. The proposed technique fully exploits workload-variation slack time by partitioning the task into several timeslots and shut down the unneeded peripheral device on timeslot-by-timeslot basis. Through extensive simulations, the novelty and the usefulness of the proposed technique are demonstrated.
Software development for next generation communication networks
Authors: Richard A. DeMillo
Venue: ACM SIGSOFT Software Engineering Notes (2000)

Even casual observes have to notice the dramatic changes in the telecommunications industry that have taken place in the last five years. Giant companies split, merge and are sometimes displaced by newer ones that did not exist a decade ago. The business of running the mighty circuit-switched telephone netwok is under constant assault on one side from packet networks and on the other side from the bewildering array of wireless networks. Service providers compete for customer sometimes with no network infrastructure at all.
A constraint solving-based approach to analyze 2D geometric problems with interval parometers
Authors: Robert Joan-Arinyo, Nuria Mata, Antoni Soto-Riera
Venue: Proceedings of the sixth ACM symposium on Solid modeling and applications (2001)

Many applications of geometric nature can be modeled by geometric problems defined by constraints in which the constraint parameters have interval uncertainty. In a previous work, we developed a method for solving geometric constraint problems where parameters are narrow intervals in the domain of the geometric problem. Based on this work, we present a new approach to solve more general problems with non-trivial-width interval parameters that may not necessarily be in the domain of the problem. We show how our approach is successfully applied to a number of problems like solving geometric problems with tolerances, checking constraint feasibility and analyzing link motion of planar mechanisms.
Solution of Eigenvalue problems with approximately known Eigenvectors
Authors: Klaus Appel
Venue: Communications of the ACM (1962)

It is often desired to solve eigenvalue problems of the type (A - &lgr;1)C = 0 or (A - &lgr;B)C = 0 repeatedly for similar values of the matrix elements Aij, where A and B are Hermitean or real symmetric matrices. Among the various methods to find all eigenvalues and eigenvectors, Jacobi's method of two-dimensional rotations [1] has been very popular for its numerical stability, although it is comparatively time-consuming. The purpose of this note is to show how existing subroutines can be used to reduce substantially the computing time, if approximate eigenvectors are known from the previous solution of a similar problem.
A unifying look at data structures
Authors: Jean Vuillemin
Venue: Communications of the ACM (1980)

Examples of fruitful interaction between geometrical combinatorics and the design and analysis of algorithms are presented. A demonstration is given of the way in which a simple geometrical construction yields new and efficient algorithms for various searching and list manipulation problems.