ppxscal/embedding_network huggingface dataset:
Performance Visualization of a Distributed System: A Case Study
Authors: Hank Jakiela
Venue: Computer (1995)

Distributed systems are increasingly being used to handle large, business-critical on-line applications that demand guaranteed, quick end-user response times. However, tools for managing performance in distributed systems are not as mature as tools for single systems, and improved ways of handling system-wide performance problems are needed to reduce the cost and complexity of building and managing distributed systems. This case study describes the use of a simple visualization technique to help resolve difficult performance problems in a large distributed system. The use of application-level trace information provides a high-level overview of system behavior that complements the information provided by lower level and component-specific performance tools. Response time problems caused by lock contention, queueing delays, and soft faults can be easily identified with this technique.
Systems with Low Distributed Simulation Overhead
Authors: D. Kumar
Venue: IEEE Transactions on Parallel and Distributed Systems (1992)

Distributed simulation often involves a large number of overhead messages. This may lead to severe performance degradation of the simulator as pointed out in several previous works. In this work special classes of systems which can be simulated with low overhead-in most systems identified here the total number of overhead messages on any given communication line is at most one, irrespective of the time up to which the physical system is to be simulated-are presented. This includes acyclic systems, some closed queuing networks, some open cyclic queuing networks, and other special types of cyclic networks. Distributed simulation algorithms specially tailored to these systems are given. By isolating these classes of systems and designing distributed simulation algorithms specifically geared for them, a large number of overhead messages can be avoided. By contrast, other distributed simulation algorithms are usually designed for more general systems and they usually require too many overhead messages, even in simulating these special classes of systems.
Focus Groups as a Knowledge Elicitation Technique: An Exploratory Study
Authors: A. P. Massey, W. A. Wallace
Venue: IEEE Transactions on Knowledge and Data Engineering (1991)

The authors examine whether one technique for group knowledge elicitation, focus groups, can provide different thoughts and judgments about a problem than individual interviews. The experimental situation was based on the resolution of an ill-structured problem by experienced subjects in a field setting. Videotaped scenarios were used to describe the situation for knowledge acquisition. Ten subjects were used, five for individual interviews and five for the focus groups. It was found that focus groups performed better in generating original responses than individual interviews and that focus groups were at least as good as individual interviews in terms of the quality and acceptability of ideas.
Recent Advances in Hierarchical Reinforcement Learning
Authors: Andrew G. Barto, Sridhar Mahadevan
Venue: Discrete Event Dynamic Systems (2003)

Reinforcement learning is bedeviled by the curse of dimensionality: the number of parameters to be learned grows exponentially with the size of any compact encoding of a state. Recent attempts to combat the curse of dimensionality have turned to principled ways of exploiting temporal abstraction, where decisions are not required at each step, but rather invoke the execution of temporally-extended activities which follow their own policies until termination. This leads naturally to hierarchical control architectures and associated learning algorithms. We review several approaches to temporal abstraction and hierarchical organization that machine learning researchers have recently developed. Common to these approaches is a reliance on the theory of semi-Markov decision processes, which we emphasize in our review. We then discuss extensions of these ideas to concurrent activities, multiagent coordination, and hierarchical memory for addressing partial observability. Concluding remarks address open challenges facing the further development of reinforcement learning in a hierarchical setting.
Link and System Level Performance of Multiuser Detection CDMA Uplink
Authors: Antti Toskala, Harri Holma, Seppo Hämäläinen
Venue: Wireless Personal Communications: An International Journal (1998)

The link level performance and the cellular system capacity in the uplink direction of a CDMA cellular system utilising multiuser detection base station receivers is analysed by simulation. In the receiver, parallel multistage multiuser detection is employed together with two-antenna diversity reception and fast closed-loop power control. A system level simulator is built to utilise the link level simulation results and to show the increase in cellular capacity obtained by using multiuser detection. The capacity is studied in urban micro and macro-cell environments utilising the channel models developed in the European CODIT project. The modelling of the environment specific and CDMA specific features is considered in the system simulator. The system level simulator is calibrated with analytical capacity calculations.
Online Check and Recovery Techniques for Dependable Embedded Processors
Authors: Matthias Pflanz, Heinrich Theodor Vierhaus
Venue: IEEE Micro (2001)

Efficient online check and fast recovery techniques for embedded systems aim to detect single or multiple errors within the same clock cycle in which they occur. Such techniques can enable fast error correction; detection of illegal states; micro-rollback for transient and permanent faults; and prioritized, controlled recovery.
Diagnosability and Diagnosis of Algorithm-Based Fault-Tolerant Systems
Authors: B. Vinnakota, N. K. Jha
Venue: IEEE Transactions on Computers (1993)

Parallel processing architectures are commonly used for signal processing and other computationally intensive applications. These applications are characterized by high throughput and long processing periods. Such characteristics decrease the reliability of high-performance architectures. The erroneous data produced by faulty processors could have damaging consequences, particularly in critical real-time applications. It is therefore desirable that any erroneous data produced by the system be detected and located as quickly as possible. Algorithm-based fault tolerance (ABFT) is a low-cost system-level concurrent error detection and fault location scheme. Methods used in the analysis of multiprocessor systems using system-level diagnosis are applied to the analysis of ABFT systems. A new algorithm for analyzing an ABFT system for its fault diagnosability is developed using these methods. Based on this work, a fault diagnosis algorithm is developed for ABFT systems.
The Real-Time Specification for Java
Authors: Greg Bollella, James Gosling
Venue: Computer (2000)

New languages, programming disciplines, operating systems, and software engineering techniques sometimes hold considerable potential for real-time software developers. A promising area of interest-but one fairly new to the real-time community-is object-oriented programming. Java, for example, draws heavily from object orientation and is highly suitable for extension to real-time and embedded systems.Recognizing this fit between Java and real-time software development, the Real-Time for Java Experts Group (RTJEG) began developing the real-time specification for Java (RTSJ) in March 1999 under the Java Community Process. This article explains RTSJ's features and the thinking behind the specification's design. The goal of the RTJEG, of which the authors are both members, was to provide a platform-a Java execution environment and application program interface (API)- that lets programmers correctly reason about the temporal behavior of executing software.
A polynomial algorithm for lot-size scheduling of two type tasks
Authors: Mikhail Y. Kovalyov, Marcus Pattloch, Günter Schmidt
Venue: Information Processing Letters (2002)

We study the problem of scheduling unit time tasks of two types on m parallel identical machines. For each type, given numbers of tasks are required to be completed by the specified deadlines. These tasks leave the system at the deadlines. The in-process inventory capacities are given. The objective is to construct a schedule that minimizes the number of changeovers occurring between the tasks of different types. This problem arises, for instance, in the production of gear-boxes on transfer lines and in the tobacco industry. Pattloch and Schmidt [Discrete Appl. Math. 65 (1996) 409-419] give an O(mH) algorithm to solve this problem where H is the latest deadline. We present here a modification of that algorithm with O(K min{K, m}), time complexity where K is the number of deadlines.
Bus encoding to prevent crosstalk delay
Authors: Bret Victor, Kurt Keutzer
Venue: Proceedings of the 2001 IEEE/ACM international conference on Computer-aided design (2001)

The propagation delay across long on-chip buses is increasingly becoming a limiting factor in high-speed designs. Crosstalk between adjacent wires on the bus may create a significant portion of this delay. Placing a shield wire between each signal wire alleviates the crosstalk problem but doubles the area used by the bus, an unacceptable consequence when the bus is routed using scarce top-level metal resources. Instead, we propose to employ data encoding to eliminate crosstalk delay within a bus. This paper presents a rigorous analysis of the theory behind "self-shielding codes", and gives the fundamental theoretical limits on the performance of codes with and without memory. Specifically, we find that a 32-bit bus can be encoded with 40 wires using a code with memory or 46 wires with a memoryless code, in comparison to the 63 wires required with simple shielding.
The Evolution of Quality Processes at Tata Consultancy Services
Authors: Gargi Keeni
Venue: IEEE Software (2000)

Tata Consultancy Services has been benchmarking itself against different quality models since the early '90s. All the TCS centers have been ISO 9001 certified since 1995. Seven of TCS's 17 development centers in India have been assessed at Software CMM Level 5, and one center has been assessed at Level 4. Although TCS started benchmarking itself with the Software CMM in 1996, the foundation for these quality initiatives was laid way back in the '80s. This article describes the path traversed and the lessons learned.The ISO 9000 initiative institutionalized the audit process and was instrumental in instituting an organization-wide quality management system. Quantitative process management provided an organizational perspective into the process capability through statistical process control. The Level 5 key process areas of Software CMM v1.1 provided a framework for reducing rework and evaluating new processes and technologies.These initiatives have benefited the organization, employees, and customers.
Mobile Agent Middleware for Mobile Computing
Authors: Paolo Bellavista, Antonio Corradi, Cesare Stefanelli
Venue: Computer (2001)

Mobile computing requires an advanced infrastructure that integrates support protocols, mechanisms, and tools to dynamically reallocate and trace mobile users and terminals and permit coordination of mobile entities. Solutions to these issues require compliance with standards to interoperate with different systems and legacy components and a reliable security infrastructure based on standard cryptographic mechanisms and tools. The secure and open mobile agent (SOMA) distributed programming framework implements three mobile computing services-user virtual environment (UVE), mobile virtual terminal (MVT), and virtual resource management (VRM). UVE provides users with a uniform view of their working environments independent of current locations and specific terminals. MVT extends traditional terminal mobility by preserving the terminal execution state for restoration at new locations. VRM allows mobile users and terminals to maintain access to resources and services by requalifying the bindings and moving specific resources or services to permit load balancing and replication. The authors' implementation of their mobility middleware confirmed that a layered, modular, mobile agent-based service infrastructure can support a range of mobile computing requirements. They conclude that SOMA's UVE, MVT, and VRM service layer provides a flexible middleware that application designers can use to deploy Internet services in an environment where users, terminals, resources, and services are all mobile.
Embedded Timing Analysis: A SoC Infrastructure
Authors: Sassan Tabatabaei, André Ivanov
Venue: IEEE Design Test (2002)

This SoC infrastructure core is a flexible, scalable, and highly accurate embedded time interval analyzer (ETIA), used to measure a variety of timing-related SoC characteristics, including jitter. The ETIA requires little design and area overhead and performs accurately under process and environment variation and noise.
Geometric surface smoothing via anisotropic diffusion of normals
Authors: Tolga Tasdizen, Ross Whitaker, Paul Burchard, Stanley Osher
Venue: Proceedings of the conference on Visualization '02 (2002)

This paper introduces a method for smoothing complex, noisy surfaces, while preserving (and enhancing) sharp, geometric features. It has two main advantages over previous approaches to feature preserving surface smoothing. First is the use of level set surface models, which allows us to process very complex shapes of arbitrary and changing topology. This generality makes it well suited for processing surfaces that are derived directly from measured data. The second advantage is that the proposed method derives from a well-founded formulation, which is a natural generalization of anisotropic diffusion, as used in image processing. This formulation is based on the proposition that the generalization of image filtering entails filtering the normals of the surface, rather than processing the positions of points on a mesh.
The Parallel Complexity of Embedding Algorithms for the Solution of Systems of Nonlinear Equations
Authors: A. Chakraborty, D. C. S. Allison, C. J. Ribbens, L. T. Watson
Venue: IEEE Transactions on Parallel and Distributed Systems (1993)

Embedding algorithms used to solve nonlinear systems of equations do so by constructing a continuous family of systems and solving the given system by tracking the continuous curve of solutions to the family. Solving nonlinear equations by a globally convergent embedding algorithm requires the evaluation and factoring of a Jacobian matrix at many points along the embedding curve. Ways to optimize the Jacobian matrix on a hypercube are described. Several static and dynamical strategies for assigning components of the Jacobian to processors on the hypercube are investigated. It is found that a static rectangular grid mapping is the preferred choice for inclusion in a robust parallel mathematical software package. The static linear mapping is a viable alternative when there are many common subexpressions in the component evaluation, and the dynamic assignment strategy should only be considered when there is large variation in the evaluation times for the components, leading to a load imbalance on the processors.
A role for computer science in user services
Authors: John Beidler
Venue: Proceedings of the 7th annual ACM SIGUCCS conference on User services (1979)

Structured programming, structured Walk-through, design languages, pseudocode processors, etc., are just a few of the buzz words that are floating around today in computer science. But just how relevant are these concepts in supporting the variety of expertise and different levels of sophistication of computer users that exist in an academic environment. On one hand we have users who only want results and don't care how dirty their programs are, just as long as they work. On the other hand, we have faculty who wish to have their students use programs in undergraduate courses and therefore they are very conscious of the programs reliability and ease of use. We believe that students majoring in computer science, when properly trained, can do a tremendous job improving user services.Through an NSF CAUSE grant, our Department of Mathematics and Computer Science became directly involved in user services. Simply stated, we see three types of user support:1. Passive - This is simply saying that the equipment is here, if you want to use it, go ahead, and good luck;2. Reactive - The computer system is here, if you want to use it, give us a call and we will give you a hand;3. Active - The system is here and it has lots of capabilities, let's go out and do things to make it easier for people to use our system and let's make an active effort to make people aware of what we can do for them.We hope that no one in user services performs the passive role. Although we might all like to think of ourselves as being active, the fact is that we do spend a good deal of our efforts reacting to the requests of others. But what kinds of things can we do to become more active in our support for others? Here we describe some of the things we have done to take advantage of the training of some of our computer science majors. Our results are not all tremendous successes, but we do feel that we have made some progress and we do have some ideas on how we can continue with this approach in our attempts to improve user services.
Stationary points of the finite length constant modulus optimization
Authors: Hamadi Jamali, Tokunbo Ogunfunmi
Venue: Signal Processing (2002)

Existing studies of the stationary points of the constant modulus adaptive algorithm, typically, assume a channel equalization setting and several restrictive conditions on the source sequence, the communications channel and the noise environment. Often, results are presented in terms of the combined channel and equalizer impulse response parameters, the source vector and the channel convolution matrix. As such, these results are not easily applicable in other areas. Modeling after Wiener filtering theory, this paper derives new expressions for the basic equations of the constant modulus (CM) optimization method. In particular, new formulas for the index function, its gradient vector and its Hessian matrix are obtained. These formulas involve the unknown parameters and the statistics of the sample sequence only. Consequently, they serve to convert the CM minimization problem into that of solving a system of cubic equations in the parameter vector. This new formulation of the CM optimization problem leads to a characterization of the critical points that is not exclusive to channel equalization. It also makes it possible to derive new equations for the minimum value of the cost function, the conditions for perfect signal recovery, and a tighter lower bound for the approach. Computer simulation examples are also presented to illustrate our findings.
Interpretation bijective d'une recurrence des nombres de Motzkin
Authors: Serge Dulucq, Jean-Guy Penaud
Venue: Discrete Mathematics (2002)

The purpose of this note is to give a combinatorial proof of the three-term linear recurrence for Motzkin numbers. The present work is inspired by Rémy's combinatorial proof of the linear recurrence for Catalan numbers (RAIRO Inform. Theor. 19(2) (1985) 179) and the more recent proof given by Foata and Zeilberger (J. Combin. Theory Ser. A 80(2) (1997) 380) for Schröder numbers (Z. Math. Phys. 15 (1870) 361).
Smoothing Method for Minimax Problems
Authors: Song Xu
Venue: Computational Optimization and Applications (2001)

In this paper, we propose a smoothing method for minimax problem. The method is based on the exponential penalty function of Kort and Bertsekas for constrained optimization. Under suitable condition, the method is globally convergent. Preliminary numerical experiments indicate the promising of the algorithm.
The exact isoperimetric inequality for ternary and quaternary cubes
Authors: Tomaz Slivnik
Venue: Discrete Mathematics (2002)

We extend the well-known edge-isoperimetric inequality of Harper, Bernstein and Hart to ternary and quaternary cubes. More generally, let Q be the graph with vertex set V = Πi=1n [Ki] in which x ∈ V is joined to y ∈ V if for some i we have |xi - yi| = 1 and xj = yj for all j ≠ i. If k1 ≥ ... ≥ kn and k2 ≤ 4, we prove that for any 0 ≤ m ≤ |V|, no m-set of vertices of Q is joined to the rest of Q by fewer edges than the set of the first m vertices of Q in the lexicographic ordering on V.
Case study: medical web service for the automatic 3D documentation for neuroradiological diagnosis
Authors: S. Iserhardt-Bauer, P. Hastreiter, T. Ertl, K. Eberhardt, B. Tomandl
Venue: Proceedings of the conference on Visualization '01 (2001)

This case study presents a medical web service for the automatic analysis of CTA (Computer Tomography Angiography) datasets. It aims at the detection and evaluation of intracranial aneurysms which are malformations of cerebral blood vessels. To obtain a standardized 3D visualization digital videos are automatically generated. The time-consuming video production caused by the manual delineation of structures, software based volume rendering, and the interactive definition of an optimized camera path is considerably improved with a fully automatic strategy. Therefore, a previously suggested approach [11] is applied which uses an optimized transfer function as a template and automatically adapts it to an individual dataset. Furthermore, we introduce hardware-accelerated morphologic filtering in order to detect the location of mid-size and giant aneurysms. The actual generation of the video is finally integrated into a hardware accelerated off-screen rendering process based on 3D texture mapping ensuring fast visualization of high quality. Overall, clinical routine can be considerably assisted by providing a web based service combining automatic detection and standardized visualization.
Complete arcs in inversive planes over prime fields
Authors: Éva Hadnagy, Angelo Sonnino
Venue: Discrete Mathematics (2002)

We construct arcs in inversive planes of prime order p, and show that these arcs are complete provided that p is sufficiently large.
The Alpha 21364 Network Architecture
Authors: Shubhendu S. Mukherjee, Peter Bannon, Steven Lang, Aaron Spink, David Webb
Venue: IEEE Micro (2002)

The Alpha 21364 processor provides a high-performance, scalable, and reliable network architecture with a router that runs at 1.2 GHz and has a peak bandwidth of 22.4 Gbytes/s. Supporting configurations of up to 128 processors, this network architecture is well suited for communication-intensive server applications.
Early Package Analysis: Considerations and Case Study
Authors: David P. LaPotin, Toufie R. Mazzawy, Marlin L. White
Venue: Computer (1993)

Several issues associated with multichip module (MCM) system design are discussed. An early analysis tool for evaluating the tradeoffs between a design and packaging technology is presented. A case study of a possible design point suggested by combining different package elements being used in MCMs settings is included. The case study indicates that the most effective packaging solution for high-performance applications, requiring multichip modules, will likely represent a progression from cofired ceramics (MCM-C) to a thin-film and hybrid cofired ceramic (MCM-D/C) module.