bluuebunny/crossref_metadata_2025 huggingface dataset:
VLSI circuit design supported by computer system simulation
Authors: Nelson John
Published: January 2007

Satisfying the enormous signal processing demands of space based sensors in the next decade is beyond the capability of integrated circuit technology as we know it today. However the performance promise of digital VLSICs (Very Large Scale Integrated Circuits) should make this problem soluble if the right device technologies, computational algorithms and computer architectures can be selected which best exploit VLSI for this application. In this space sensor signal processor design study, computer system simulation using the language ECSS (Extendable Computer System Simulator) proved to be the key to performing tradeoffs and developing designs which could meet the stressing demands for low power and high computational throughput.
A simulation model for equipment selection in a steel plant
Authors: Nassau Pedro A.
Published: January 2007

A simulation model was developed to determine the optimal policy for utilization and replacement of moving equipment in a steel plant. Specifically, this paper deals with the problem of slag removal in a melt-shop composed of a batch of five electric-arc furnaces. The environment of high temperatures in which service has to take place leads to conditions of frequent equipment break-down and a dynamic rescheduling of activities, which makes the use of simulation a necessity. One important feature that was included in the model was the process of "aging", that is, that service time is a function of the number of minutes that the slag has been waiting for its removal.
Marine terminal facilities planning through simulation
Authors: Batra Pradeep
Published: January 2007

This paper reviews the development of an interactive vessel scheduling and crude oil monitoring system for crude shipments from Alaska to the West Coast ports. The prime consideration in developing a computerized model was to provide an operational tool for scheduling the movements of a fleet of ARCO owned and chartered vessels. Utilizing the operating characteristics and design criteria obtained from the various operating groups, a model was developed to simulate the activities of the tanker fleet, the supply sources in Alaska, and the demand centers on the West Coast. For a given set of starting conditions, the model generates management reports that summarize crude inventory statistics at Alaska and West Coast ports, tanker lifting and delivery timings, refinery runouts at the demand centers and penalty situations at the supply sources.
Conversion of long integers from one base to another under size constraints
Authors: Kovats T. A.
Published: January 2007

A long integer is a vector whose elements are the digits of a number represented in a number system based on a given base; this construct is useful in extended-precision calculations. A routine is presented for converting a long integer froe one base to another, as well as routines for doing addition and multiplication of long integers.
The situation is this ....
Authors: Ellinger Robert S.
Published: January 2007

One normally accepted taxonomy classifies simulations into continuous, discrete, and hybrid. But this taxonomy fails to note a significant division of simulations, particularly for the purposes of instruction and personnel training. Most business and research simulations--and many instructional simulations--are of the laboratory type (see figure 1). The simulation operator sets up the operating conditions--i.e. the values of the independent variables and parameters that define the initial state--then allows the computer model to run. This model is usually a set of mathematical functions that are sequenced by an algorithm and may contain one or more stochastic variables. This is the type of simulation subdivided in the taxonomy.
Some problems in the design of combined languages
Authors: Barnden J. A.
Published: January 2007

The purpose of this article is to air some problems and issues I have encountered on trying to derive principles for the design of combined continuous-discrete simulation languages for digital computers [1, 2, 3, 4, 5]. The presentation is intended to provoke discussion rather than to provide definitive analysis. I am especially conerned with: interaction between parallel' components; discontinutuity and the discrete/continuous dichotomy; and state-events.
General fast generation of random variables for discrete distributions
Authors: Brown Theodore
Published: January 2007

Recently a new method, the alais method has been introduced for generating a discrete, finite valued distribution (1, 2). The method is exceptionally fast and can be broadly applied. It should have wide appeal. The purpose of this note is to introduce the method, place it in prospective with other fast, generally applied methods and to provide a Fortran program to generate constants needed by the method for any given distribution.
Some experiences in interfacing a PL/I module with GPSS-V
Authors: Cooespoti D. J.
Published: January 2007

While conductins a research project, it was necessary to make an extensive number of executions using two large GPSS-V models. In order to consolidate the statistics produced by GPSS from these runs, it was decided to interface a PL/I module with GPSS-V using the HELPCPLI block. The PL/I module accesses the GPSS data structures and writes information selected from them to a data set. The data set is then used to consolidate the statistics using separate PL/I programs. The following is a brief summary of some experiences encountered while attempting to achieve the interface.
A Monte Carlo approach for the solution of the simple quadratic and cubic self-avoiding random walk
Authors: Myers Buddy L. , Enrick Norbert L. , Redmond Richard T. , Lindgren John H.
Published: January 2007

A procedure for virtually memory-free Monte-Carlo simulation of the self-avoiding random walk (SAW) in a two-dimensional network and in a simple cubic lattice has been developed. It is highly efficient in yielding values of the intrachain meansquare end-to-end distance <r
2
n
> for chains up to n = 1000 and n = 400 steps, for the two and three-dimensional cases respectively. The number N of walks per each chain of n steps involved n = 500 to N = 3000.
Risk analysis and sensitivity analysis
Authors: Kleijnen Jack P. C.
Published: January 2007

If a dynamic model assumes parameters constant over time, then the posterior mean (i.e. the mean conditional on specific values of these parameters) is relevant. Since parameters are unknown, they must be estimated. Sensitivity analysis quantifies the effects of incorrectly specified values of the parameters. If these effects are important then additional information on the parameters might be collected; otherwise robust solutions are to be sought. If these options do not work then risk analysis can quantify the probability of specific outputs, incorporating the probability distribution of the estimated parameters. Sensitivity analysis changes the values of parameters systematically, whereas risk analysis samples the parameter values. Simple queuing and econometric examples illustrate the two approaches.
Knowledge engineering problems during expert system development
Authors: Chubb Douglas Walter J.
Published: January 2007

Expert systems are artificial intelligence computer programs which emulate human expertise within some domain of interest. The recent financial successes of such expert systems as PROSPECTOR and XCON have created a demand in government and industry for the developmental skills necessary to build such systems. Expert system knowledge engineering and in particular knowledge acquisition continues to be the most difficult process encountered during expert system develpment. Reasons for knowledge acquisition difficulties find their basis in philosophical assumptions made about the cognitive process. The assumptions are that human cognition consists of discrete elements which may be characterized (by some introspection) to produce an expert system rule; secondly, that the processing requirements for expert domain heuristics is equivalent to the processing requirements for a deterministic rule set. Suggestions for improving the knowledge engineering process are offered.
The quality of a scientific simulation
Authors: Sherman G. R.
Published: January 2007

Demonstrable high quality of a simulation of the disposal of nuclear fuel waste is crucial for the assessment of the disposal concept. The elements of quality are described, as pertaining to models of the controlling processes, data interpreted from field and laboratory measurements, and computer software representing the models.Procedures for quality assurance and features that enhance quality are discussed. Two major factors are identified: comparison and critical review. Simulation data and results can be compared with field and laboratory observations, with alternate solutions, or with expert judgment. Critical review by scientists and other interested parties, facilitated by thorough documentation, can ensure that the appropriate processes are being accurately modeled.
Simulation as a tuning tool in TSO
Authors: Chapman John
Published: January 2007

The production TSO system at Standard Oil has been running since August 1973. Prior to this date, several limited test systems with small user groups were run, to collect information on modifications necessary to support interactive programming in a manner which would conform to current application development needs and practices. To support program development under O.S. Time Sharing Option, it was necessary to modify IBM supplied code, as well as add code, to the system. The experiments which led to the definition of the modifications needed included a six-month long test system to support a single, small group of application programmers. At the conclusion of this test, the programming group involved estimated an increase in productivity (groupwide) of twenty to thirty-five percent.
Monte Carlo simulation and its statistical design and analysis
Authors: Kleijnen Jack P. C.
Published: January 2007

In this paper we shall discuss statistical aspects of the numerical technical called Monte Carlo simulation. In the present section we examine Monte Carlo simulation in general. Any solution method using random numbers (or pseudorandom numbers) we call a Monte Carlo method. As we know random numbers are stochastic variables that are uniformly distributed on the interval [0.1] and are statistically independent. On digital computers random numbers are approximated by pseudorandom numbers, i.e. numbers generated by deterministic algebraic formulas and for practical purposes considered to be purely random. Presently, the most used formula is the multiplicative congruential one, i.e. x
i
= a x
i-1
+ b (mod m) for i = 1, 2, ..., with prespecified a,b, m and x
0
. It is recommended to permute the resulting (pseudo) random numbers, r
i
= x
i
/m, in order to improve their statistical independence. Numerous publications on random number generation are available. For briefness' sake we mention only the bibliography (with 491 references) by Nance and Overstreet (1972): Marsaglia (1972) giving a table of recommended values for a when m = 2
32
, 2
35
, 2
36
; and Lewis (1972). Transformations of random numbers can yield any other stochastic variable. For recent results, see Ahrens and Dieter (1972), Andrews et al. (1972, p. 56), Mihram (1972, p. 94--146), Nance and Overstreet (1972), Newman and Odell (1971, p. 18--52).
A quick GPSS quiz
Authors: Schriber Thomas J.
Published: January 2007

The Problem Corner feature for this issue takes the form of a one-question quiz for those SIGSIM members who know GPSS. The quiz question is given immediately below. The answer to the quiz appears at the bottom of the page, upside down.
Keeping up with the Watsons
Authors: Solomon Susan L.
Published: January 2007

GPSS 1100 is the most recent implementation of the GPSS programming language on the large-scale UNIVAC systems, specifically including the UNIVAC 1108. The language has been in existence for several years now, and has evolved through the usual versions and growing pains. It offers a number of imaginative innovations when compared with its predecessor, GPSS/360, not to mention GPSS II, which was the only previous option of the UNIVAC user. However, despite the spadework done in GPSS/360 for at least five years prior to the birth of GPSS 1100, some excellent features of that language were not included in GPSS 1100 or continue to have bugs preventing their use.
The anatomy of GASP IV
Authors: Wortman David B.
Published: January 2007

The development of a new simulation language, GASP IV, is announced. Who cares? Why should you bother to invest the time to learn the peculiarities of someone else's design? You would rather do it yourself and be certain of the results, or would you? I would like to try to convince you that GASP IV is capable of satisfying your simulation needs by providing the answers to those questions most often asked about this new and powerful simulation language.
What hath got Roth
Authors: Roth Paul F.
Published: January 2007

I was in Atlanta earlier this year and had the occasion to visit the wax museum at Underground Atlanta. Near the end of the tour, two events occured which have a bearing on Charlie McCarthy.
Simulation documents available
Authors: Oren Tuncer I.
Published: January 2007

The NTIS (National Technical Information Service) collection includes (i) Government-sponsored research and development reports, (ii) Government analyses prepared by Federal agencies, their contractors or grantees, (iii) Federally sponsored translations, and (iv) some reports written in foreign languages. The NTIS reports exist in paper copy or in microfiche unless otherwise specified and are available indefinitely. To order the documents contact: NTIS, P.O. Box 1552, Springfield, Virginia 22151.
Optimizing simulated systems
Authors: Pflug Georg Ch.
Published: January 2007

A major part of all simulation models contains a number of decision variables. For such models the problem of optimal decision arises in a natural way. The combination of simulation and optimization for probabilistic models with continuous decision variables is discussed in this paper. Several important techniques for solving the combined problem are presented. In particular the stochastic quasigradient method which is a well known technique in stochastic optimization may also successfully applied for simulation-optimization problems.
Implications of the ADA® environment for simulation studies
Authors: Friel Patricia , Sheppard Sallie
Published: January 2007

Ada packages to support event and process oriented simulation have been developed at Texas A&M University. These packages include standard Facilities such as queue handling, random number generation, automatic statistics collection and simulation control. This paper provides an overview of the system facilities followed by an evaluation of the strengths and weaknesses of Ada as an implementation language for simulation software. Based on our experience Ada has appeal as a general purpose language which can be integrated into larger systems. It is portable among various computer architectures, it provides a rich base of constructs in which to implement models, and offers promise in terms of execution on parallel architectures.
Problem oriented protocol design
Authors: Nicol David M. , Reynolds Paul F.
Published: January 2007

The prevention of deadlock in certain types of distributed simulation systems requires special synchronization protocols. These protocols often create an excessive amount of performance-degrading communication; yet a protocol with the minimum amount of communication may not lead to the fastest network finishing time. We propose a protocol that attempts to balance the network's need for auxiliary synchronization information with the cost of providing that information. Using an empirical study, we demonstrate the efficiency of this protocol. Also, we show that the synchronization requirements at different interfaces may vary; an integral part of our proposal assigns a protocol to an interface according to the interface's synchronization needs.
Random deviates from the DIPOLE distribution
Authors: Knop Robert E.
Published: January 2007

The function subprogram DIPOLE, written by Robert E. Knop of the Physics Department, The Florida State University at Tallahassee FL 32306, returns a random deviate -∞ < z < ∞ sampled from the two parameters (R
2
< 1, α arbitrary) family of the density function: f(z) = 1/(π (1+ z
2
)) + R
2
* ((1 - z
2
) * cos(2α) + 2* z* sin(2α) / (π * (1+z
2
)
2
).
Uniform random number generator
Authors: Stryk Robert A.
Published: January 2007

The recent flurry of random number routines and your continued plea for material had led me to dust off my favorite trick uniform random number generator. It requires no seed, produces numbers uniformly distributed between 0 and 1, is acyclic and for all practical purposes, is completely unpredictable and irreproducible.
Uniform random number generator by shift register method
Authors: Highland Harold Joseph
Published: January 2007

The quixotic quest for the perfect random number generator has been an overriding factor for a group of simulation purists. Although we have developed a series of tests for the evaluation of random number generators, only a few of us engaged in modeling and simulation have actually taken the time to analyze the generators we use; most are willing to accept the random number generators available on the system - just because it is there!
Additional APL generators
Authors: Halmstad David G.
Published: January 2007

The following are some additional generator routines to supplement those published by Robert E. Wheeler. The first is the (usual?) straight-forward routine for the
geometric
distribution. The second is for the generation of the highest (or lowest) variates in ordered samples (from the uniform distribution). When one has the inverse of the distribution function being used, this routine is rather useful. A self-explanatory demonstration of the use of the
PORDER
generator is shown in conjunction with the use of
WEIBULL
distribution generator.
Validation
Authors: Edgecomb Gordon D. , Thompson Richard J.
Published: January 2007

In simulation exercises some degree of validation is necessary in order to create confidence in the results obtained. Experienced users of generalized simulation software and commercially available simulation tools often find that the majority of their simulation efforts are localized in the validation cycle. Discussed in this paper are some of the factors which have caused the validation process to become more complicated and more time consuming. This paper also summarizes the major problems with simulating complex computer systems and suggests some basic requirements and design philosophies for new simulation packages.
A man/machine workload model
Authors: Willis Ronald R.
Published: January 2007

The fundamental nature of computer systems is to serve the user. If we wish to evaluate the performance of a computer system, we must therefore seek to characterize its responsiveness to those actions initiated by the user. It is this responsibility that isolates accurate workload distributions as an imperative ingredient in computer systems evaluation, and it is this ingredient that the man/machine workload model addresses.In particular, the model presented here simulates human activity at a terminal in real-time or time-share computer system environments. The use of flowcharts to represent human decision making and a variable language definition capability to code flowchart actions are key to the approach. The techniques described stress automatic and manual verification as well as the ability to accurately represent workloads at the point where workloads originate, the human.With this representative approach, accurate workload generation is a natural outcome. In addition, experience has shown that the man/machine workload model serves to enhance computer system simulation credibility, provide a tradeoff tool for human factors and operations design "what-if" questions, and most importantly, to provide a validation methodology for front-end system design efforts.
A Monte Carlo simulation for data processing students
Authors: Trombetta Michael
Published: January 2007

In the typical two-year data processing program there is so much material that must be covered that inevitably some important subjects are given abbreviated coverage or eliminated entirely. For example, almost all of our programming assignments and examples involve the use of computers in "accounting" type problems, in spite of the fact that computers are widely used to solve "operations research" type problems. This paper discusses a simple simulation problem which can be used to introduce data processing students to the use of computers to solve operations research type problems.
A simulation-based scheduling and management information system for a machine shop
Authors: Jain Suresh K.
Published: January 2007

This paper describes the design, working, performance, costs and benefits of a computerized scheduling and management information system that has been developed for a large, generalized
m/n
machine shop which had previously been a bottleneck facility in the Cast Roll Manufacturing complex of Bethlehem Steel Corporation. A flexible discrete-event simulation model, at the heart of the computer system, generates two types of schedules: Planning Schedules for making long- and medium-term planning and operating decisions, and Production Schedules for sequencing approximately 1000 rolls on 40 machines on a day-to-day basis.A number of supporting programs perform data management, file management, and report-generation functions. Data-collection functions are deliberately performed manually to avoid the high costs associated with automatic data-collection equipment normally used in large computer systems. The computer programs are run in a time-sharing environment. A cathode ray tube and a medium-speed printer are the only hardware requirements of the system. With the implementation of the computer system, significant improvement is now being obtained as measured by productivity, labor and machine efficiencies, due date performance, and work-in-process inventory. The computer system is saving Bethlehem a substantial amount of money every year, and a notable feature of this system is its low annual operating cost.
Simulation of scheduling methods for operating systems
Authors: Lamie Edward L.
Published: January 2007

One of the criticisms leveled against GPSS is that it is too "general purpose" to be of much value in certain specialized areas. This criticism has also been applied to the modeling of operating systems and some individuals have discounted the value of GPSS in this area because of the mistaken belief that it is not possible to change the priority of an inactive transaction.
Sales order processing
Authors: Bekiroglu Haluk
Published: January 2007

GPSS simulation of the customer order processing through the warehouse containing packaged items at a large chemical plant in St. Louis, Missouri, is described. Objective is to determine the service rate on a certain type of order and by varying the number of warehouse personnel at key positions to obtain comparison service rates for management review.
Simulation techniques for travel demand forecasting
Authors: Mannering Fred L.
Published: January 2007

The article presents an overview of some simulation techniques that were developed for use in a recent research effort. The objective of the research was to create a modeling system with the power to evaluate the travel-related impacts of various proposed transportation energy contingency plans, such as increased fuel taxes, reduced speed limits, mandatory vehicle modification, and so on. Traditional modeling efforts in this area have had substantial data requirements which have made their use awkward or impossible in many situations. The use of various simulation procedures in the present model has substantially reduced data requirements while maintaining a high level of forecasting capability.
Simulation of operating systems
Authors: Francis N. D.
Published: January 2007

A functional flowchart for simulating 0.S/360 under HASP is presented. The flow chart which uses some of the GPSS concepts is simple and easy to understand and the methodology can be easily adapted for simulating other operating systems in any high level language.
The discrete event simulation computer - DESC
Authors: Barel Meir
Published: January 2007

Simulation of large models on digital computers is often limited by the high computational expenses. The Discrete Event Simulation Computer (DESC) reported here improves simulation performance through an exploitation of parallelism inherent in simulation, with regard to list processing, random number generation, statistical analysis and program control. The DESC consists of a set of nodes that communicate via FIFO-buffered channels (i.e. do not share memory among nodes). In order to achieve high system throughput dedicated hardware modules were developed; this includes new concepts for a list processor and a hardware random number generator for uniform deviates.The implementation of simulation languages such as SIMULA, SIMSCRIPT or GPSS is conceptually straightforward. We chose SIMULA as the frame language concept. Metrics applicable to simulation throughput and simulation costs are defined and compared with the CD CYBER 175.
A tutorial view of simulation model development
Authors: Nance Richard E.
Published: January 2007

Working from the background of simulation language developments, we develop an understanding of the current status of simulation model development. Factors characterizing the current status include a shift in emphasis from program to model, more commitment to modeling tools, and the lingering impedance of simulation language isolation. Current and future needs are identified. Specific approaches to meeting these needs are cited in an extensive description of current research, and in summary we conclude that the technology of simulation model development is in a transitional period that portends more rapid changes for the future.
MASIM
Authors: Auer Hans , Maschtera Ulrike
Published: January 2007

In this paper a process-oriented simulation language and its implementation via the macroprocessor MORTRAN (in Fortran IV) are described. The advantages of the presented language are its modular structure, data typing and its problemoriented simulation operations. The essential point of the implementation was to show, in what an easy way a process-oriented language including modern software concepts can be implemented in "old and wide-spread" Fortran.
Archaic to modern 1
Authors: Nagle Dan
Published: January 2007

Including the new Fortran 2003, there are three revisions of the Fortran standard beyond the venerable, quarter-century-old Fortran 77. While the newer revisions, Fortran 90, 95 and 2003, have standardized more features, they are (very nearly) upwards compatible with Fortran 77. In fact, many of the new features are standardisation of extensions implemented by Fortran 77 compilers, albeit each with its own spelling. Still, the introduction of modern Free Format in place of the card-image-based Fixed Format, and the overall amount of new features (many first appearing in the Fortran 90 standard), means that some applications programmers consider modern (90, 95, 2003) Fortran to be a different language than archaic (66, 77) Fortran.
Stream input/output in Fortran
Authors: Page Clive
Published: January 2007

Traditionally, and indeed until the advent of Fortran2003, Standard Fortran I/O has been entirely record-based. This is fine if you are reading or writing a file of records such as a text file, where each line is a record, since it means that you don't need to be concerned about the record terminators (which, depending on the platform, may be line-feeds, or carriage-returns, or both). It can, however, be a serious handicap when you want to use Fortran to read a file generated by some instrument, or produced by a package such as a spreadsheet or database system. Often these files do not have records that Fortran can recognise, or they have a more complex structure than a simple linear sequence of records, but Standard Fortran has not previously provided any means of accessing them simply as a stream of bytes or characters. Another problem is that sometimes one wants to access the records in some random order, rather than in a strict sequence. One can do this in Fortran using direct-access files, but these are restricted to files where all records have the same length. Stream I/O provides solutions to all these problems.
Parallel programming
Authors: Chivers Ian D. , Sleightholme Jane
Published: January 2007

The Fortran language has been standardised a number of times• Fortran 66• Fortran 77• Fortran 90• Fortran 95• Fortran 2003and Fortran 2008 is work in progress.
Technical contributions describing activities underway
Authors: Saltzman Alan
Published: January 2007

In the November 1978 issues of Datamation, in an arcticle entitled "The Changing Face of Applications Programming", Daniel McCracken, President of the ACM, defined procedural versus non-procedural languages. He says that "despite improvements the productivity of today's programmers is no more than two of three times the productivity of programmers a quarter of a century ago. In the same period, the price performance ratio of the computer hardware has improved by a factor of perhaps a million. People wanting to use this low cost hardware are frustrated by the handicaps imposed by writing programs in...procedural languages." He goes on to state that "by the mid-80's more than half of all computer time will be spent running applications programs constructed with non-procedural oriented languages." (Many companies have already become aware of the cost benefits of non-procedural languages and are already using them. Schering-Plough was to be one of these astute companies).
Case records of the Meshugunah General Hospital
Authors: Cabot Sebastian C. , Lee Robert E. , Potter Sherman T. , Againstya Betty
Published: January 2007

A 7-year-old female was admitted to the hospital bacause of paralysis and suspicion of a lung lesion.
The transient analysis of loss networks
Authors: Tian Wenhong
Published: January 2007

Unlike stationary behavior, time-dependent blocking probabilities for loss networks are not well understood and little work has been done except for the single service center case. We propose novel closed-form transient analysis methods for single Erlang loss system and networks, to the best of our knowledge, these are the most efficient ways to analyze the transient behavior of Erlang loss system and networks. Applying this model, time-dependent provisioning can satisfy dynamically changed traffic demands and avoid overprovisioning problem in connection-oriented loss networks.
Guest editor's foreword
Authors: Papagiannaki Konstantina , Zhang Yin
Published: January 2007

In recent years, large scale network inference has attracted significant interest within the research community. On one front, considerable progress has been made on traffic matrix estimation. Solutions have been proposed to estimate the amount of traffic flowing between any pair of ingress and egress points within an IP network simply based on the total amount of traffic recorded over IP links. On another front, efforts are being made to detect the state of the network from end to end measurements using inference techniques or to infer the traffic workload by exploiting application behavior. In essence, the full instrumentation of the state of an IP network is still considered a cost prohibitive task and inference may be the only tool we have to understand the behavior of such large scale systems. The potential benefits of the proposed estimation techniques can be great. Accurate measurement of an IP traffic matrix is essential for network design and planning. Moreover, accurate estimation of the network state can facilitate troubleshooting and performance evaluation.
Local area network analysis using end-to-end delay tomography
Authors: Lawrence Earl , Michailidis George , Nair Vijay N.
Published: January 2007

There has been considerable interest over the last few years in collecting and analyzing internet traffic data in order to estimate quality of service parameters such as packet loss rates and delay distributions. In this paper, we focus on fast and efficient estimation methods for network link delay distributions based on end-to-end measurements obtained by probing the underlying. We introduce a rigorous statistical framework for designing the necessary probing experiments and examine the properties of the proposed estimators. The proposed framework and the resulting methodology are validated using data collected on the University of North Carolina (UNC) local area network.
PGMLISH or r u there?
Authors: Nussbacher Henry
Published: January 2007

Campus computing is unique in one aspect that the "real world" tends often to down-play and more often to ignore. That is, inter-terminal communication plays a vital part in student programming and computing. While waiting for a job to run or just sitting reading an output, it is possible for your tranquility to be interrupted by a message beeping to life on your screen, asking, "Hi, who r u?"
The SIGIR 2005 workshop program
Authors: Oard Douglas W.
Published: January 2007

The SIGIR 2005 workshop program included seven workshops that were competitively selected from among eight proposals. Organizers of SIGIR 2004 workshops had reported that tight timelines for publicizing workshops and reviewing submissions had resulted in some workshop participants not being notified that a workshop paper had been accepted until the deadline for registration at regular prices had passed. The submission date for SIGIR 2005 workshop proposals was therefore advanced to occur one week after full papers were due. Expedited reviews of all workshop proposals were performed by a committee consisting of recent workshops chairs, augmented where necessary with additional reviewers to ensure that expertise in the topic of each workshop proposal was available. The review results were summarized in an email to the organizing committee and area chairs, and decisions were made by the PC chairs after an email discussion. Workshop organizers were notified of their selection shortly after the poster deadline, about 5 weeks earlier than in previous years. As a result, workshop organizers were generally able to solicit and review submissions sufficiently rapidly to permit workshop participants to qualify for discounted early registration rates.
Future short term goals of research in computational analysis of stylistics in text
Authors: Argamon Shlomo , Karlgren Jussi , Shanahan James G.
Published: January 2007

The first workshop on stylistic analysis of text for information access was held on the day following the 2005 SIGIR conference. This workshop addressed the automatic analysis and extraction of stylistic aspects of natural language texts. Style, roughly defined as the 'manner' in which something is expressed, as opposed to the 'content' of a message is usually disregarded by information access applications as having no bearing on the target notion of relevance: systems have typically focused on the "factual" aspect of content analysis.
Multimedia information retrieval
Authors: Manmatha R. , Rüger Stefan , Hauptmann Alex
Published: January 2007

The Multimedia Information Retrieval workshop at SIGIR'05 was well attended with about 28 participants. The workshop format consisted of 8 papers on a variety of different topics from features and representations for image retrieval to a complete retrieval system for media monitoring. The list of papers may be seen at http://mmis.doc.ic.ac.uk/mmir2005/, where many of the papers are available online. A substantial amount of time was set aside for discussion of issues in multimedia retrieval, and this report will focus on the discussion.
Report on the INEX 2005 workshop on element retrieval methodology
Authors: Trotman Andrew , Lalmas Mounia
Published: January 2007

On the 30
th
July 2005, a workshop on XML element retrieval methodology was held as part of the Information Retrieval Festival at the University of Glasgow. Ten papers were presented in four sessions. Each session addressed one aspect of the methodology of XML IR: metrics, users, interactive / heterogeneous, and judging (relevance ranking was excluded). This report outlines the events of the workshop and the major outcomes.
Finite fans, actions of tori and
D
-modules
Authors: Rueda Sonia L.
Published: January 2007

Let
G
be a finite dimensional torus acting diagonally on the smooth affine variety
X
=
k

r

x (
k

x

)

s

, with
k
an algebraically closed field
k
of characteristic 0. We denote the ring of regular functions on
X
by
O
(
X
) and the ring of differential operators by
D
(
X
). Let
D
(
X
)

G

be the subring of
D
(
X
) of invariants under the action of
G
.The goal of this poster is to show how finite fans of cones can be used to study
D
(
X
)

G

-modules. We associate a finite fan of cones to the action of
G
on
X
, in such a way that the study of the fan will allow us to get conclusions about the finite dimensional
D
(
X
)

G

-modules. We describe next the basic ingredients of our construction.
2D and 3D generalized Stewart Platforms
Authors: Gao Xiao-Shan , Zhang Gui-Fang
Published: January 2007

The
Stewart Platform
(SP) is a parallel manipulator consisting of a moving platform and a base. The position and orientation (pose) of the base are fixed. The base and platform are connected with six extensible legs. The SP has been studied extensively in the past 20 years and has many applications. A large portion of the work on SP is focused on the direct kinematics: for a given set of lengths of the legs, determine the pose of the platform. It is known that the direct kinematics have 40 solutions. But, closed form solutions are not found yet.
An approach to singularity from the extended Hensel construction
Authors: Sasaki Tateaki , Inaba Daiju , Katamachi Kentaro
Published: January 2007

Let
F
(
x,u
), with (
u
) = (
u
1
,...,
u
ℓ
), be an irreducible multivariate polynomial over C, having singularity at the origin, and let
F
New
(
x,u
) be the so-called Newton polynomial for
F
(
x,u
). The extended Hensel construction (EHC in short) of
F
(
x,u
) allows us to compute the Puiseux-series roots if ℓ = 1 and, for ℓ ≥ 2, the roots which are fractional-power series w.r.t. the (weighted) total-degree of
u
1
,...,
u
ℓ
. This paper investigates the behavior of algebraic function χ(
u
) around the origin, where χ(
u
) is a root of
F
(
x,u
), w.r.t. the variable
x
, and clarifies a close relationship between the singularity of χ(
u
) and the corresponding Hensel factor. Let the irreducible factorization of
F
New
in C[
x,u
] be
F
New
(
x,u
)

m

1
...
H

r

(
x,u
)

m

. It is shown that: 1) the procedure of EHC distributes the factors of the leading coefficient of
F
(
x,u
) to mutually prime factors of
F
New
in a unique way, and the "scaled-root"
x
(
u
) becomes infinity only at the zero-points of the leading coefficient of the corresponding factor of
F
New
(
x,u
); 2) the behavior of χ(
u
) around the origin changes singularly at zero-points of resultant(
H

i

,
H

j

) (∀
i
≠
j
), resultant(
H
i
,∂

H
i

/∂
x
) (
i
= 1,...,
r
), and
fcirc;
ℓ
(ℓ = 1,...,ρ), where
f
ℓ
is the sum of terms plotted at the ℓ-th vertex of bottom sides of the "Newton polygon". We explain these points not only theoretically but also by examples.
Irreducible decomposition of monomial ideals
Authors: Gao Shuhong , Zhu Mingfu
Published: January 2007

In this paper we present two algorithms for irreducible decomposition of monomial ideals. We first use staircase structures to study the monomial ideals. We generalize the shifting degrees rule from two variables to three variables and then arbitrary case. With the aid of monomial tree representation, a new algorithm for irreducible decomposition of monomial ideals is provided. For the second method, we associate a monomial ideal with a Scarf complex, which is introduced by Herbert Scarf. Every facet of the Scarf complex corresponds to an irreducible component, and vice versa. Milowski(2004) developed a method to enumerate all the facets based on reverse search by exchanging one monomial at a time. We define a facet graph where nodes are facets and there is an edge from a facet

F
A

to another facet

F
B

if

F
B

can be obtained from

F
A

by exchanging one vertex. We give a new generic deformation called ordinal deformation and prove that the facet graph of an ordinally generic monomial ideal is strongly connected. This yields a simpler and more efficient enumeration algorithm.
Review of "Probability and Statistics with Reliability, and Computer Science Applications, by Kishor S. Trivedi"
Authors: von Mayrhauser Anneliese
Published: January 2007

Designed as an introduction into basic probability theory and statistics with heavy emphasis on analytic modeling of various aspects of computer systems and their workloads, this book turns out to be much more than a text for a course or for self-study. Seen as a textbook, it provides knowledge understandably and quite comprehensively by addressing topics ranging from basic probability theory, stochastic processes, queueing theory to statistical inference and analysis of variance. Each topic is well presented. An incredible wealth of examples addresses modeling issues of computer systems and workload behavior for performance analysis, capacity planning, as well as reliability and availability considerations. This alone should put the book onto the professional's and student's bookself. Additionally, an excellent reading list, classified by topics, provides useful direction for further study. As a whole, the book is very understandable yet sophisticated enough to serve the professional with previous modeling experience as a reference text. It is remarkably well written, understandable, well-organized and naturally was quite a success with my students when I used it as a textbook for a graduate course on modeling. In short, it is a very valuable and worthwhile book which should become a classic text.
Review of "Probability and Statistics with Reliability, and Computer Science Applications, by Kishor S. Trivedi"
Authors: Blanks John P.
Published: January 2007

Given the complexity and size of modern Design Automation problems, it is obvious that in the future statistical techniques will be much more widely employed. One is reminded of the state of physics before thermodynamics, and we might hazard the analogy that there are some problems which can only be treated by statistical methods. The laws of large numbers come freely into plan when partitioning and routing circuits with components numbering into the thousands.
Job statistics at a 2000-user university computer center
Authors: Ishida Haruhisa , Takahashi Nobumasa
Published: January 2007

The Computer Centre at the University of Tokyo is one of 7 large university centers serving researchers throughout Japan; it processes 120,000 jobs annually submitted by 2,000 academic users in various research institutions. A brief comparison of the 7 centers and the breakdown of users are shown. To clarify the job characteristics of these users, account data of all jobs in an entire year were analyzed and the results are presented.They are shown in terms of the distribution of CPU time, numbers of input cards/output pages/output cards, program size, job end conditions and turnaround time etc. A special on-line card punch is mentioned which punches holes in the 13th row to separate output card decks. It was found that, when the CPU speed was increased 8 times after replacement under the same operating system, the average job size was increased 4 times. Hence only twice as many jobs could be processed. The results of analysis have been used for systems performance evaluation (for example, the CPU busy-rate was found to be 69%), improvement and for an input job model used in planning for the next system.
The software empiricist
Authors: Kolence Kenneth W.
Published: January 2007

The advent of software and hardware monitoring technology has presented us with a flood of data, without bringing commensurate understanding by which to interpret it. Thus, the most important problem before us in the field of computer measurement is to discover the relationships between the variables we measure and the overall system properties of interest. Particularly, we wish to be able to predict system behavior and performance from a knowledge of the values of factors under our control. In this way, not only will we understand the meanings of these variables, but we shall learn how to design our systems to perform as we wish them to. The latter is a prime goal of software engineering, the former the rational of what has been called software physics. In this section of the Review we are and shall be interested in the empirical development of such an understanding, and the experimental aspects of computer measurement. Our intent is to assist in the building of a solid body of knowledge by providing a publication vehicle for empirical and experimental data. That is, we have little interest in publishing theory, which can normally be done elsewhere. Our goal is to publish experimental data to support or refute theory, and empirical data from which theory builders may take their inspiration.
What is statistical design?
Authors: Sapatnekar Sachin
Published: January 2007

In the nanoscale regime, the effects of variations can dramatically affect circuit behavior. These variations may arise from fluctuations in the manufacturing process (e.g., drifts in channel length, oxide thickness, threshold voltage, or doping concentration), which affect the circuit yield, as well as variations in the environmental operating conditions (e.g., supply voltage, temperatures, or particle strikes that lead to soft errors) after the circuit is manufactured, which affect the correctness of the behavior of the design. Some of these variations are entirely deterministic (metal fill density, etc.), while others are random, as their cause is either unknown, or unattributable, or too difficult to model.Circuit performance is known to vary significantly under process and environmental variations: significant changes in timing can result, and the leakage power, which depends exponentially on process parameters, can be greatly affected. Unlike traditional deterministic analysis, where performance values at worst-case process/voltage/temperature corners are computed, statistical analysis determines the probability distributions for the timing or the power.Practical statistical static timing analysis (SSTA) methods proceed in a block-based manner in the fashion of deterministic STA algorithms, and use determine the probability distributions of the arrival time at the gate outputs, while statistical leakage power analysis techniques use probabilistic methods to determine the distribution of the leakage. The performance yield can be computed by using these distributions to determine the fraction of manufactured circuits that satisfy timing and power constraints. Statistical optimization changes the design parameters of the circuit to improve the performance yield.