ppxscal/embedding_network huggingface dataset:
First Passage Times in Fluid Models with an Application to Two Priority Fluid Systems
Authors: A. Narayanan, V. G. Kulkarni
Venue: Proceedings of the 2nd International Computer Performance and Dependability Symposium (IPDS '96) (1996)

In this paper we analyze the first passage time in a fluid flow model where the input and output rates are controlled by a finite state Continuous Time Markov Chain (CTMC). We derive explicit expressions for the Laplace Transform of the joint distribution of the first time the buffer becomes empty and the state of the CTMC at that time. We discuss both infinite and finite buffer cases. We illustrate the results with the case of a fluid model with an on-off source. We apply these results to a fluid model where the input consists of two types of fluid and a single server removes the fluid. The server gives complete priority to the fluid of type 1 over that of type 2. In this case the down time of the server for priority 2 fluid is the same as the busy period of the fluid of priority 1. We derive the steady state marginal distributions of the buffer-content process for fluids of type 1 and 2. We present numerical results and their interpretations.
An Emerging International Standard for Software Process Assessment
Authors: David Kitson, Loretta Kitson
Venue: Proceedings of the 4th IEEE International Symposium and Forum on Software Engineering Standards (1999)

In June 1993, an international effort was chartered by ISO/IEC JTC1 to develop a standard for software process assessment. An important goal of this effort is to harmonize existing software process assessment approaches. This tutorial focuses on: Promoting a clear understanding of the prospective international standard (officially designated as ISO/IEC 15504 TR). Exploring its implications for Capability Maturity Model (CMM)-based software process assessment -globally, the most widely adopted approach to software process assessment and developed by Carnegie Mellon University's Software Engineering Institute. The tutorial will address the following aspects of this important work: The history, current status and future plans of the international collaborative effort to produce a standard for software process assessment. How it will impact CMM-based assessment; this discussion will include both the current CMM V1.1 baseline as well as its successor product suite currently being developed by the CMM Integration (CMMI) Project. How the prospective standard is likely to impact the global software marketplace. This tutorial is targeted at both potential sponsors and managers of software process improvement efforts, as well as software process assessment and improvement practitioners.
Power Macromodeling for a High Quality RT-Level Power Estimation
Authors: R. Zafalon, M. Rossello, E. Macii, M. Poncino
Venue: Proceedings of the 1st International Symposium on Quality of Electronic Design (2000)

Several approaches that address early power estimation in digital design have been published in the last years. Most of them are based on a fast (coarse) logic synthesis step, in order to analyze power on the mapped gate-level netlist. In this paper we present a summary of RTPow, a proprietary tool dealing with the RT-level power estimation, relying on a top-down estimation engine that does not perform any type of on-the-fly logic synthesis when analyzing the HDL description. In addition, a set of power macromodeling capabilities have been developed as well, to enable an effective power budgeting and automatic bottom-up power characterization methodology.
Plans and Strategies in Explanation Dialogues
Authors: Giacomo Ferrari, Irina Prodanof, Michele Carenini
Venue:  (1991)

In this paper the plan-based approach to discourse modelling is briefly discussed and its inadequacy to the tratment of explanatory discourse is shown. The need for a static representation of communication schemata is advocated, and, consequently, the requirements for such a representation are laid down. A graph-like formalism is selected and some examples of its use are discussed in detail. Finally, a preliminary formal definition of an ATN-like metalanguage is attempted. TEL:: +39 50 560481
Meta-Dialogue Behaviours: Improving the Efficiency of Human-Machine Dialogue -- A Computational Model of Variable Initiative and Negotiation in Collaborative Problem-Solving
Authors: I C Guinn
Venue:  (1995)

This is a study of communication in collaborative problem-solving. We provide a model of collaboration that integrates {\bf natural language dialogue} and {\bf multi-agent planning}. Agents are assumed to be autonomous, but they only possess limited knowledge and capabilities. Although the agents may share the same common goal, they do not have direct access to their collaborators'' knowledge and plans. Agents must use natural language dialogue to request resources from other agents, provide assistance to others, coordinate problem-solving and negotiate conflicts. Kartram and Wilkins argue that the most important issues for evaluating single-agent planners are {\em soundness}, {\em completeness}, {\em optimality}, {\em efficiency} and {\em search control}. We believe these same criteria should be used in evaluating multi-agent problem-solvers. In this thesis, we identify the domain conditions and dialogue behaviors necessary for soundness and completeness within our model of collaboration. We provide an account of efficiency and search control within the model. We show that the dialogue mechanisms of {\bf variable initiative} and {\bf negotiation} vastly improve the efficiency and search control of the collaborative problem-solving between two agents. We demonstrate that the benefit of variable initiative and negotiation mechanisms cannot be realized without proper plan recognition. We show that a particular class of {\bf summarizing statements} can enhance plan recognition and thereby greatly improve the efficacy of these mechanisms. We examine and verify our model of collaboration using both analytical and experimental means. We analyze the collaborative model by presenting an explicit algorithm that each collaborating agent uses during problem-solving. We call this algorithm the {\bf Collaborative Algorithm}. Using this explicit formalism, we can determine the properties necessary for soundness, completeness and efficiency of the algorithm. The Collaborative Algorithm has been implemented, and computer--computer problem-solving experiments have been conducted in several domains. These experiments validate the conclusions of the formal analysis. Furthermore, these computer--computer problem-solving sessions provide a technique for exploring behaviors of the Collaborative Algorithm that cannot be formally analyzed. 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
A Systems Engineering Approach for Constructing Certifiable Real-Time Distributed Systems
Authors: Binoy Ravindran, Gérard Le Lann, Jinggang Wang, Peng Li
Venue: Proceedings of the Sixth IEEE International Symposium on Object-Oriented Real-Time Distributed Computing (2003)

In this paper, we present a systems engineering methodology for constructing certifiable real-time distributed systems. In the proposed approach, an architectural and algorithmic solution to an application problem is designed by considering the "weakest" models including the weakest asynchronous computational model and multimodal arrival model. Furthermore, timeliness properties are described using Jensen's benefit accrual predicates. Once a system solution is designed, timeliness properties are established by constructing necessary feasibility conditions that are expressed as non-valued predicates. The predicates are quantified and verified to produce the specification of a certified solution. We illustrate the approach by considering a packet transmission problem that desire soft timeliness. We present a certifiable solution to this problem that consists of switched Ethernet, a soft real-time packet scheduling algorithm (that was previously developed), and feasibility conditions.
Mermera: Non-coherent Distributed Shared Memory for Parallel Computing
Authors: Himanshu Sinha
Venue:  (1993)

Abstract The proliferation of inexpensive workstations and networks has prompted several researchers to use such distributed systems for parallel computing. Attempts have been made to offer a shared-memory programming model on such distributed memory computers. Most systems provide a shared-memory that is {\em coherent} in that all processes that use it agree on the order of all memory events. This dissertation explores the possibility of a significant improvement in the performance of some applications when they use {\em non-coherent} memory. First, a new formal model to describe existing non-coherent memories is developed. I use this model to prove that certain problems can be solved using asynchronous iterative algorithms on shared-memory in which the coherence constraints are substantially relaxed. In the course of the development of the model I discovered a new type of non-coherent behavior called {\em Local Consistency}. Second, a programming model, {\sc Mermera}, is proposed. It provides programmers with a choice of hierarchically related non-coherent behaviors along with one coherent behavior. Thus, one can trade-off the ease of programming with coherent memory for improved performance with non-coherent memory. As an example, I present a program to solve a linear system of equations using an asynchronous iterative algorithm. This program uses all the behaviors offered by {\sc Mermera}. Third, I describe the implementation of {\sc Mermera} on a BBN Butterfly TC2000 and on a network of workstations. The performance of a version of the equation solving program that uses all the behaviors of {\sc Mermera} is compared with that of a version that uses coherent behavior only. For a system of 1000 equations the former exhibits at least a 5-fold improvement in convergence time over the latter. The version using coherent behavior only does not benefit from employing more than one workstation to solve the problem while the program using non-coherent behavior continues to achieve improved performance as the number of workstations is increased from 1 to 6. This measurement corroborates our belief that non-coherent shared memory can be a performance boon for some applications.
The Visibility of Maintenance in Object Models: An Empirical Study
Authors: Mikael Lindvall, Magnus Runesson
Venue: Proceedings of the International Conference on Software Maintenance (1998)

This empirical study analyzes changes in C++ source code which occurred between two releases of an industrial soft ware product and compares them with entities and relations available in object-oriented modeling techniques. The comparison offers increased understanding of what changes can and cannot be described using such object models. The goals were to investigate if the object model in this particular project is either abstract and stable or detailed and sensitive to change, and whether or not changes made to the C++ source code are visible in the object model. Four metrics for characterization of change are formally defined and used, namely correctness, completeness, compliance, and visibility factor. The major finding is that even though many of the classes are changed, the majority of these changes turn out to be invisible in the object model. That is, changes made on the source code level are of a finer granularity than available in common object modeling concepts. This may explain why object models seem to be of little use in release-oriented development.
Detecting Dominant Point on On-line Scripts with a Simple Approach
Authors: Su Yang, Guozhong Dai
Venue: Proceedings of the Eighth International Workshop on Frontiers in Handwriting Recognition (IWFHR'02) (2002)

We proposed a new dominant point detection method.It has the following advantages: robustness, computational efficiency, and real-time response to pen movement. We construct a variable that is the ratio of the height to the width of an imagined rectangle whose bottom coincides with the polygon enclosed by the pen movement trace,and area is equal to thepolygonal area. For we are on-line watching whether the value of this variable exceeds agiven threshold, we can find dominant points in real-time. Only when the fluctuation comparing to the scale of a curve is big enough, value of this variable can exceed the given threshold. By this way, pseudo turning points can be rejected. As a new point comes in, only a small number of computations are needed to update the value of this variable. Effectiveness of thismethod was confirmed by experiments.
Convexity and Logical Analysis of Data
Authors: Oya Ekin, Peter L. Hammer, Alexander Kogan
Venue:  (1998)

A Boolean function is called $k$-convex if for any pair $x,y$ of its true points at Hamming distance at most $k$, every point ``between'''' $x$ and $y$ is also true. Given a set of true points and a set of false points, the central question of Logical Analysis of Data is the study of those Boolean functions whose values agree with those of the given points. In this paper we examine data sets which admit $k$-convex Boolean extensions. We provide polynomial algorithms for finding a $k$-convex extension, if any, and for finding the maximum $k$ for which a $k$-convex extension exists. We study the problem of uniqueness, and provide a polynomial algorithm for checking whether all $k$-convex extensions agree in a point outside the given data set. We estimate the number of $k$-convex Boolean functions, and show that for small $k$ this number is doubly exponential. On the other hand, we also show that for large $k$ the class of $k$-convex Boolean functions is PAC-learnable.
Hoppix-an implementation of a Unix server on a persistent operating system
Authors: E. Z. Bem, A. Lindstrom, S. Norris, J. Rosenberg
Venue: Proceedings of the 5th International Workshop on Object Orientation in Operating Systems (IWOOOS '96) (1996)

Hoppix-the Unix server on the Grasshopper operating system is being implemented to provide a familiar environment for research and experimentation in persistence. The server is constructed using the basic Grasshopper abstractions: containers, loci, capabilities, container invocations and locus private mappings. The above abstractions enable a full implementation of a POSIX compliant interface at the user-level without compromising security and protection. The paper discusses specific issues related to creation of the Unix address space and the Unix file system, and implementation of fork and exec system calls.
Precision Locking for Nested Transaction System
Authors: John K Lee
Venue:  (1993)

This paper presents and verifies the improved version of precision locking that eliminates the locking overhead and deadlock prone aspects of the idea described in [5] and avoids the phantom problem. It extends the algorithm to nested transactions systems.
Trimmed L-moments
Authors: Elsayed A. H. Elamir, Allan H. Seheult
Venue: Computational Statistics Data Analysis (2003)

Classical estimation methods (least squares, the method of moments and maximum likelihood) work well in regular cases such as the exponential family, but outliers can have undue influence on these methods. We define population trimmed L-moments (TL-moments) and corresponding sample TL-moments as robust generalisations of population and sample L-moments. TL-moments assign zero weight to extreme observations, they are easy to compute, their sample variances and covariances can be obtained in closed form, and they are more robust than L-moments are to the presence of outliers. Moreover, a population TL-moment may be well defined where the corresponding population L-moment does not exist: for example, the first population TL-moment is well defined for a Cauchy distribution, but the first population L-moment, the population mean, does not exist. The sample TL-mean is compared with other robust estimators of location.
Algorithms for Stable Sorting to Minimize Communications in Networks of Workstations and Their Implementations in BSP
Authors: Christophe Cérin, Jean-Luc Gaudiot
Venue: Proceedings of the 1st IEEE Computer Society International Workshop on Cluster Computing (1999)

In this paper we introduce our new approach to produce BSP (Bulk Synchronous Programming model) programs and we show their efficiency by implementing the stable sorting problem on clusters of PC. Experimental results on PCs based on Ethernet and Myrinet cards are compared with implementations on an SGI 2000. The algorithms presented in the paper are either developed under the theoretical framework of the Regular Sampling technique which guarantees good load balancing properties or are inspired by the technique in order to decrease the sequential work of each processor comparing to the Regular Sampling technique but impose no (theoretical) bound on load balancing. The main sequential block of code used in the algorithms for local sorting are derivatives of Shellsort (which is stable) and a new code based on Quicksort (which is not stable) plus a property on real numbers that is used for stable sorting under the framework of BSR (Broadcast with Selective Reduction).
Speeding Up Short Data Transfers: Theory, Architectural Support, and Simulation Results
Authors: Yin Zhang, Lili Qiu
Venue:  (2000)

Today''s Internet traffic is dominated by short Web data transfers. Such a workload is well known to interact poorly with the TCP protocol. TCP uses the slow start procedure to probe the network for bandwidth both at connection start up and upon restart after an idle period. This usually requires several roundtrips and is inefficient when the duration of a transfer is short. In this paper, we propose a new technique, which we call TCP/SPAND, to speed up short data transfers. In TCP/SPAND, network performance information is shared among many co-located hosts to estimate each connection''s fair share of the network resources. Based on such estimation and the transfer size, the TCP sender determines the optimal initial congestion window size. Instead of doing slow start, it uses a pacing scheme to smoothly send out the packets in its initial congestion window. We use extensive simulations to evaluate the performance of the resulting system. Our results show that TCP/SPAND significantly reduces latency for short transfers even in presence of multiple heavily congested bottlenecks. Meanwhile, the performance benefit does not come at the expense of degrading the performance of connections using the standard TCP. That is, TCP/SPAND is TCP friendly.
On multicast routing in Clos networks
Venue: Proceedings of the 1996 International Symposium on Parallel Architectures, Algorithms and Networks (1996)

Multicast routing in high speed networks is one of the key issues in the design and implementation of applications such as video conferencing. Traditionally, the problems are formalised as either the shortest path problem or Steiner tree problem where the objective function is either the shortest path or the minimum costs associated with the path. Furthermore, the problems of multicast routing are usually line problems in the sense that the set of multicast requests to which the network is subject is static and is give in prior. In this paper, we study an online multicast routing problem in Clos network with two optimizing criteria: network throughput and quality of service (or QOS). We propose five routing algorithms according to five system measures using as routing indices. The problem to find an optimal routing according to each of these system measures corresponds to an off-line routing problem. We prove that all of these off-line routing problems except the least-busy routing problem (LB) are NP-complete. We also conduct a series of simulation experiments to study the system performance, namely, the network throughput and QOS, using these routing algorithms as on-line algorithms. The simulation results indicates that the routing algorithms have little impact on the network throughput, but have major impact on the QOS. The LB, the linear time algorithm, outperforms other algorithms while used as on-line routing algorithms as far as the QOS is concerned.
Wavelet methods in (financial) time-series processing
Authors: Zbigniew R. Struzik
Venue:  (2000)

We briefly describe the major advantages of using the wavelet transform for the processing of financial time series on the example of the S\&P index. In particular, we show how to uncover local the scaling (correlation) characteristics of the S\&P index with the wavelet based effective H\"older exponent [1, 2]. We use it to display the local spectral (multifractal) contents of the S\&P index. In addition to this, we analyse the collective properties of the local correlation exponent as perceived by the trader, exercising various time horizon analyses of the index. We observed an intriguing interplay between such (different) time horizons. Heavy oscillations at shorter time horizons which seem to be accompanied by a steady decrease of correlation level for longer time horizons, seem to be characteristic patterns before the biggest crashes of the index. We find that this way of local presentation of scaling properties may be of economic importance.
Dialog-Based Learning (DBL) for Adaptive Interface Agents and Programming-by-Demonstration Systems
Authors: Siegfried Bocionek, Michael Sassin
Venue:  (1993)

Many users of workstation and PC tools often have to perform the same task again and again. For example, a secretary might have to send out a dozen email messages until she finds a free meeting room. Or someone preparing business charts has to draw many special tables with shadowing bars around. Unfortunately, today''s macro facilities of such tools do not support the end user enough in constructing the required automation functions. In this report we propose a mechanism, called dialog-based learning (DBL), that shall provide the user of software tools exactly with a mechanism to teach new functions or to give hints or additional information to a program on how to perform a task better. Two applications will be considered: The first one is our experimental system RAP, a room reservation apprentice that will eventually overtake a secretary''s task to search for a free meeting or lecture room. RAP analyzes the outgoing and incoming email and constructs a finite state machine that can repeat the task of asking all room administrators until a free room is found. The key of RAP''s learning is to ask the user for unknown message types (e.g., request, positive answer, etc.) and keyphrases (e.g., "need a room") and to collect them in a thesaurus. Our second application is a demonstrational graphics editor that allows the user to teach it new functions by giving a few examples. The graphics editor will sometimes ask the user for explanations by showing him a list of its geometrical hypotheses for a certain situation, e.g., "line l1 was doubled" or line "l1 touches line l2 in the middle" (the second hypothesis serves as a strong indication that "touching" is the intended property). By clicking at one of them the use tells the graphics editor his intention and helps it to construct a function and a menu item for a new function. Involving the user through dialogs is an easy way to support the heuristics for function induction from examples when the hypothesis space grows. Our claim is that -- with DBL -- a Programming by Demonstration system can synthesize new functions faster, that it can synthesize more complex functions than without DBL, and that the resulting functions will meet the user''s intentions better (because he or she took part in their derivation). Therefore one can see DBL as a kind of simple inference mechanism, but with a powerful outcome.