bluuebunny/crossref_metadata_2025 huggingface dataset:
An interactive graphical interface for REDUCE
Authors: Leler Wm , Soiffer Neil
Published: January 2007

The availability of workstations with bit-mapped displays opens up new possibilities for displaying and interacting with mathematical expressions. This paper describes an interactive graphical interface to Reduce. This system displays the output from Reduce in its natural, two dimensional form. The interactivity of the workstation is used to advantage in several ways, including allowing subexpressions to be selected using a mouse and reentered into Reduce.
A new use of operators in the algebraic mode of REDUCE
Authors: Caprasse H. , Hans M.
Published: January 2007

It is apparent for many users of REDUCE [1] that in the algebraic mode many facilities available in the symbolic mode are lacking. Consequently, the programming of nontrivial problems very soon becomes unnecessarily complicated. This situation is unsatisfactory mainly for two reasons:1) Though some users will turn to the symbolic mode, many of them do not have the time to master it and are not supposed to know LISP.
A lisp-language Mathematica-to-lisp translator
Authors: Fateman Richard J.
Published: January 2007

Wide distribution of the computer algebra system Mathematica has encouraged numerous programmers, researchers and educators to produce libraries of programs in its special language, for incorporation as "packages" into Mathematica systems. Although some features of the language are quite interesting, some authors have found that for their purposes the Mathematica proprietary computer program has problematical and difficult-to-alter semantics. Therefore certain kinds of experiments and developments are necessarily inconvenient. An initial step in opening up such user-written libraries to re-use is an independent re-implementation of the language via a non-proprietary parser. In principle, this allows other implementations of semantics, as well as experiments in data representation, while still using the language basically as described in the Mathematica references. We describe a parser written in Common Lisp, a language which is appropriate for three reasons: (1) It is a standard and has wide distribution; (2) It supports numerous useful features including automatic storage allocation and garbage collection, arbitrary-precision integers, and tools for lexical scanning of languages; and (3) Lisp is the host language for several algebraic manipulation systems whose subroutines may be of some interest for programmers implementing alternative semantics.
Generalized Naive Bayes Classifiers
Authors: Larsen Kim
Published: January 2007

This paper presents a generalization of the Naive Bayes Classifier. The method is specifically designed for binary classification problems commonly found in credit scoring and marketing applications. The Generalized Naive Bayes Classifier turns out to be a powerful tool for both exploratory and predictive analysis. It can generate accurate predictions through a flexible, non-parametric fitting procedure, while being able to uncover hidden patterns in the data. In this paper, the Generalized Naive Bayes Classifier and the original Bayes Classifier will be demonstrated. Also, important ties to logistic regression, the Generalized Additive Model (GAM), and Weight Of Evidence will be discussed.
Quantifier Elimination for Real Closed Fields by Cylindrical Algebraic Decomposition
Authors: Collins George E.
Published: January 2007

This is a brief summary and exposition of the paper "Quantifier Elimination for Real Closed Fields by Cylindrical Algebraic Decomposition," which was presented at the Second GI Conference on Automata Theory and Formal Languages, University of Kaiserslautern, May 1975, and which appears in the proceedings of that conference, Lecture Notes in Computer Science, Vol. 33 (Springer Verlag, Berlin, 1975, pages 134--183). A preliminary version of this paper was presented at the EUROSAM 74 Conference, Stockholm, July 1974, and appears in the proceedings of that conference, SIGSAM Bulletin, Vol. 8, No. 3 (August 1974), pages 30--90. The final version of the paper includes a rather detailed analysis of the computing time of the algorithm, which was omitted from the preliminary version In addition, the final version describes several significant improvements to the algorithm of the earlier version.
Analysis of the binary Euclidean algorithm
Authors: Brent Richard P.
Published: January 2007

The binary Euclidean algorithm finds the GCD of two integers u and v using subtraction, shifting and parity testing. Unlike the classical Euclidean algorithm, no divisions are required. We analyse a continuous model of the binary algorithm, and find the expected number of iterations.
Syracuse information retrieval experiment (SIRE)
Authors: McGill Michael J. , Smith Linda C. , Davidson Stuart , Noreault Terry
Published: January 2007

Proponents of interactive online bibliographic retrieval systems frequently stress the potential of such systems to take advantage of both human and computer capabilities in the document retrieval process. Yet systems implemented to date have to a great extent placed constraints on both human and machine performance by decisions made at the design stage. To increase the flexibility of online systems, alternative modes of document representation, storage utilization, and query formulation should be considered.
A blueprint for automatic Boolean query processing
Authors: Salton G.
Published: January 2007

Conventional information retrieval systems use Boolean query formulations and inverted file technologies for search and retrieval purposes. The need to construct complex Boolean queries in order to obtain the benefit of the existing retrieval operations constitutes a substantial burden for the users. In most environments trained search intermediaries are used to facilitate the communication between system and user.In this note a new Boolean retrieval environment is outlined in which the queries are automatically constructed from the original natural language query formulations provided by the users. Any available Boolean query formulations can also be improved automatically by using the natural language text of previously retrieved documents identified as relevant during previous searches. The automatic queries can be formulated in a standard Boolean system, or in an extended system in which the interpretation of the Boolean operators and and or is relaxed. In either case. the automatic Boolean manipulations produce better retrieval output than conventional retrieval operations based on manually prepared query statements.
Workshop on computer architecture for non-numeric processing
Authors: Berra P. Bruce
Published: January 2007

On October 14-15, 1974 SIGIR together with SIGARCH, SIGMOD and the the IEEE Technical Committee on Computer Architecture sponsored a two day workshop on computer architecture for non-numeric processing. By all standards the workshop was a huge success primarily due to the fine papers and the efforts of Bob Korfhage and John Fike of SMU. The Conference was such a success that a second workshop is being planned on this same subject for Gainesville Florida in February 1976. For the benefit of those who were unable to attend the workshop we have included the abstracts and sunmaries here.
A resource request model for microcode compaction
Authors: Larsen Tore , Landskov David , Shriver Bruce D.
Published: January 2007

A new approach to resource conflict analysis in microcode compaction has been developed. This paper begins with a description of the resource binding problem in microcode compaction and an analysis of earlier solutions. Then a new specification technique is presented and related to a standard problem in combinatorial theory. This new technique allows microoperations to be specified with resource choices, the actual binding to specific resources being delayed until compaction time. A polynomial-time algorithm for analyzing resource conflicts under this model is explained. Further extensions to the algorithm to support more complex machine models are suggested.
Planning and financial issues
Authors: Emery James C.
Published: January 2007

It's a real pleasure, for someone that's been in the computer business as long as I have, to finally see some things happening that were predicted back in the very early days of computing.
A note on a nearest polynomial with a given root
Authors: Graillat Stef
Published: January 2007

In this paper, we consider the problem of a nearest polynomial with a given root in the complex field (the coefficients of the polynomial and the root are complex numbers). We are interested in the existence and the uniqueness of such polynomials. Then we study the problem in the real case (the coefficients of the polynomial and the root are real numbers), and in the real-complex case (the coefficients of the polynomial are real numbers and the root is a complex number). We derive new formulas for computing such polynomials.
Concepts for advanced computer assisted models
Authors: Oren Tuncer I.
Published: January 2007

Computers can provide valuable assistance in the process of modelling itself, as well as in the usability, acceptability, and referability of models.
A rule-based poison control expert system
Authors: Rubens Catherine E.
Published: January 2007

Poison Control Centers throughout the country are responsible for giving advice quickly to patients who have possibly been accidentally poisoned, There exists a need for a more reliable means of accomplishing this task.
SIGIR workshop report
Authors: Carmel David , Yom-Tov Elad , Soboroff Ian
Published: January 2007

Estimation of query difficulty is an attempt to quantify the quality of results returned by the search system for a query. Ideally, a system that can predict difficult queries can adapt parameters or change algorithms to suit the query. Such systems could give feedback to the user, for example, by reporting confidence scores for results, and report to the system administrator regarding topics that are of increasing interest to users but are not answered well by the system.
Measuring computer system utilization with a hardware and a hybrid monitor
Authors: Svobodova Liba
Published: January 2007

Computer system utilization is generally measured in terms of the utilization of individual system components and the overlap of activities of two or more system components. This type of data can be used to construct a system performance profile [BONN 69, COCI 71, SUM 70]. Utilization of a system component is obtained as the ratio (unit busy time)/(total elapsed time). If a particular unit performs more than one type of operation, the unit busy time may be further divided into portions corresponding to different activities and an activity profile can be constructed for each such unit. For a storage unit, information about utilization of different portions of storage might be desirable in addition to utilization of this unit as a whole. A space utilization profile Can be developed in this case. To cover both cases, the term unit utilization profile is used.
The maturity of open systems for B2B
Authors: Kajan Ejub
Published: January 2007

This paper deals with the B2B interoperability in the sense of open systems and available component and framework standards. Special attention is given to the common reference framework for B2B interactions at the middleware level. Some relevant frameworks at the content and business layers are also described. Finally, concluding remarks emphasize future directions in the area of B2B interoperability. Many of the highlighted issues may also be used in other e-applications and in heterogeneous distributed systems in general.
Redagent
Authors: Keller Philipp W. , Duguay Felix-Olivier , Precup Doina
Published: January 2007

The Supply Chain Management track of the international trading Agents Competition (TAC ACM) provides a challenging scenario for existing AI decision-making algorithms, due to the high dimensionality and the non-determinism of the environment. Our entry in this competition, RedAgent, is centered around the idea of using an internal market in order to determine what products to focus on and how to allocate the existing resources. This simple design provided a very efficient search mechanism, while at the same time producing price estimates for components, as well as bidding estimates on customer orders.
Value-driven procurement in the TAC supply chain game
Authors: Kiekintveld Christopher , Wellman Michael P. , Singh Satinder , Soni Vishal
Published: January 2007

The TAC supply-chain game presents automated trading agents with challenging decision problems, including procurement of supplies across multiple periods using multiattribute negotiations. The procurement process involves substantial uncertainty and competition among multiple agents. Our agent, Deep Maize, generates requests for components based on deviations from a reference inventory trajectory defined by estimated market conditions. It then selects among supplier offers by optimizing a value function over potential inventory profiles. This approach offered strategic flexibility and achieved competitive performance in the TAC-03 tournament.
Botticelli
Authors: Benisch Michael , Greenwald Amy , Grypari Ioanna , Lederman Roger , Naroditskiy Victor , Tschantz Michael
Published: January 2007

The paper describes the design of the agent BOTTICELLI, a finalist in the 2003 Trading Agent Competition in Supply Chain Management (TAC SCM). In TAC SCM, a simulated computer manufacturing scenario, BOTTICELLI competes with other agents to win customer orders and negotiates with suppliers to procure the components necessary to complete its orders. We formalize subproblems that dictate BOTTICELLI's behavior. Stochastic programming approaches to bidding and scheduling are developed in attempt to solve these problems optimally. In addition, we describe greedy methods that yield useful approximations. Test results compare the performance and computational effciency of these two techniques.
On fuzziness in relationship value segmentation
Authors: Sicilia Miguel-Ángel , García Elena
Published: January 2007

Relationship marketing strategies focus on the construction and maintenance of tailored relationship with customers. Consequently, electronic commerce systems following the relationship approach may benefit from Web personalization techniques in tailoring the interaction with its users according to an evolving customer model. In this context, relationship-value market segmentation becomes a central customer modeling activity. But value segmentation categories are inherently vague due to the use of imprecise linguistic categories, combined with a degree of uncertainty about customer behavior, and the difficulty inherent to estimating intangible variables. In this paper, a fuzzy approach to value segmentation is described, allowing more flexible customer segments. Fuzzy models of value estimations are represented by fuzzy triangular numbers, and two segmentation approaches, directed and discovery-oriented are briefly described. The usefulness of the approach is then illustrated through concrete personalization techniques based on those fuzzy categories.
NEXCESS
Authors: Yamamoto Masaki , Tomiyama Hiroyuki , Takada Hiroaki , Agusa Kiyoshi , Mase Kenji , Kawaguchi Nobuo , Honda Shinya , Kaneko Nobuyuki
Published: January 2007

In October 2004, Nagoya University has started an extension program on embedded software, called NEXCESS (Nagoya university EXtension Courses for Embedded Software Specialists). NEXCESS aims at education of engineers in industry, and is financially supported by the government. This paper describes the organization and course design of NEXCESS. Also, our experience of the first half year is reported.
Experience with an embedded systems software course
Authors: Muppala Jogesh K.
Published: January 2007

In this paper we share our experience with designing and offering a senior undergraduate course on Embedded Systems Software in the Department of Computer Science at the Hong Kong University of Science and Technology. We give a detailed overview of the course, some reflections on our experience with the first offering of the course, followed by some discussion on the students' views of the course.
A comparative illustration of AI planning-based web services composition
Authors: Oh Seog-Chan , Lee Dongwon , Kumara Soundar R. T.
Published: January 2007

As the number of available web services proliferates, finding right web services to fulfill a given goal becomes an important task. In particular, a problem of combining multiple web services to satisfy a single task, known as web services composition problem, has received much attention recently, and various solutions have been proposed. Among many proposed solutions, however, it is not clear to use which one in what scenarios. In this paper, to this end, we present: (1) a taxonomy and decision guideline of available solution spaces; (2) an overview of syntactic and semantic matching approaches, and (3) a comparative illustration of three representative solutions from the perspective of e-service workflows.
Identifying groups of computer users through factor analysis
Authors: Carson Gary L.
Published: January 2007

The purpose of this investigation is to try to classify computer center users into distinct groups or 'types' of users. The ability to break users into distinct 'groups' would be useful in job scheduling, providing user seminars, acquisition of canned programs and providing program documentation, etc.
Optimization of online disk scheduling algorithms
Authors: Zarandioon Saman , Thomasian Alexander
Published: January 2007

Disk scheduling policies have a significant effect on disk performance. SPTF is one of the well-known policies that can increase disk performance near to optimality [1]. One of the drawbacks of the regular implementation of SPTF is its high computational cost. "The computational cost [of SPTF] (as indicated crudely by our simulation times) is very high" [2]. This paper shows that computational cost of SPTF is not the characteristic of SPTF, but it is a matter of implementation. The experience shows that this approach can improve the efficiency over 80% compared to naïve implementation. Finally, an algorithm for efficient implementation of lookahead algorithms is introduced.
New challenges for evolutionary music and art
Authors: McCormack Jon
Published: January 2007

Art, it was once said, is anything you can get away with. So it is not surprising that evolutionary approaches to music and art research are challenging our notions of what is classified as "Art" and who is the "creator" of this work. The relatively new field of Evolutionary Music and Art (EMA) falls within the spectrum of Evolutionary Computing. If EC is a relatively young discipline, then EMA is even more so, if we consider Richard Dawkins' "Blind Watchmaker" software (1986) as the epoch in this field.
1
Dawkins' goal was to demonstrate the power of evolution as a design algorithm, one that could design complexity without the need for an explicit designer. It did not take long for people interested in creativity and aesthetics to grasp the significance of this idea and how it might be used to create a new class of art and design: one that was evolved rather than directly created.
Determining the end-to-end throughput capacity in multi-hop networks
Authors: Gao Yan , Chiu Dah-Ming , Lui John C.S.
Published: January 2007

In this paper, we present a methodology to analytically compute the
throughput capacity
, or the maximum end-to-end throughput of a given source and destination pair in a multi-hop wireless network. The end-to-end throughput capacity is computed by considering the interference due to neighboring nodes, as well as various modes of hidden node interference. Knowing the throughput capacity is important because it facilitates the design of routing policy, admission control for realtime traffic, as well as load control for wireless networks. We model location-dependent neighboring interference and we use a contention graph to represent these interference relationships. Based on the contention graph, we formulate the individual link capacity as a set of fixed point equations. The end-to-end throughput capacity can then be determined once these link capacities are obtained. To illustrate the utility of our proposed methodology, we present two important applications: (a)
route optimization
to determine the path with the maximum end-to-end throughput capacity and, (b)
optimal offered load control
for a given path so that the maximum end-to-end capacity can be achieved. Extensive simulations are carried out to verify and validate the proposed analytical methodology.
The impact of reneging in processor sharing queues
Authors: Gromoll H. Christian , Robert Philippe , Zwart Bert , Bakker Richard
Published: January 2007

We investigate an overloaded processor sharing queue with renewal arrivals and generally distributed service times. Impatient customers may abandon the queue, or renege, before completing service. The random time representing a customer's patience has a general distribution and may be dependent on his initial service time requirement.We propose a scaling procedure that gives rise to a fluid model, with nontrivial yet tractable steady state behavior. This fluid model captures many essential features of the underlying stochastic model, and we use it to analyze the impact of impatience in processor sharing queues. We show that this impact can be substantial compared with FCFS, and we propose a simple admission control policy to overcome these negative impacts.
Fluid modeling of pollution proliferation in P2P networks
Authors: Kumar Rakesh , Yao David D. , Bagchi Amitabha , Ross Keith W. , Rubenstein Dan
Published: January 2007

P2P systems are highly vulnerable to pollution attacks in which attackers inject multiple versions of corrupted content into the system, which is then further proliferated by unsuspecting users. However, to our knowledge, there are no closed-form solutions that describe this phenomenon, nor are there models that describe how the injection of multiple versions of corrupted content impacts a clients' ability to receive a valid copy. In this paper we develop a suite of fluid models that model pollution proliferation in P2P systems. These fluid models lead to systems of non-linear differential equations. We obtain closed-form solutions for the differential equations; for the remaining models, we efficiently solve the differential equations numerically. The models capture a variety of user behaviors, including propensity for popular versions, abandonment after repeated failure to obtain a good version, freeloading, and local version blacklisting. Our analysis reveals intelligent strategies for attackers as well as strategies for clients seeking to recover non-polluted content within large-scale P2P networks.
Optimizing transmission rate in wireless channels using adaptive probes
Authors: Guha Sudipto , Munagala Kamesh , Sarkar Saswati
Published: January 2007

We consider a wireless system with multiple channels where each channel is either on or off, and probing the state of any channel incurs a cost. We present a polynomial time algorithm that determines which channels to probe and also which channel to transmit so as to maximize the difference between the rate of successful transmissions and the cost incurred in probing.
Relating number of processing elements in a sparse distributed memory model to learning rate and generalization
Authors: Evans Richard M. , Surkan Alvin J.
Published: January 2007

A simulated neural network was developed with APL on an 80386 microcomputer. The network was configured to associate task descriptions with 10 categories of military occupational specialties. The number of processing elements in the problem was varied. Increasing the number of processors increased the speed of learning in the simulation. Generalization was not significantly different for various numbers of processing elements except for one intermediate number at which generalization occurred about 15 percent higher. Analysis of the performance of a trained network suggests that low level, natural language understanding is one form of text processing which promises to become an important application area for neural model-based computing.
Application of nested arrays to databases for engineering design
Authors: Hazony Yehonathan
Published: January 2007

A major problem facing the manufacturing industry in its quest for improved productivity is the integration of Computer-Aided-Design (CAD) and Computer-Aided-Manufacture (CAM) to form systems for "seamless design-to-manufacture" (SDTM). This article describes the use of APL2 to build such an integrated system, as opposed to trying to integrate existing systems which are commercially available. The main advantages offered by APL2 are due to the combination of extensive database services, provided by nested arrays in a large workspace, and the accessibility of such data to a rich set of sophisticated mathematical tools. An "Expert-System-Generator" (ESG[1]), built in APL2, makes it possible to build a customized SDTM system which circumvents many of the problems associated with the task of integration of separate commercial systems.
Building an APL2 X-Windows interface for VM and AIX with a general APL2-to-C interface
Authors: Jensen John R. , Beaty Kirk A.
Published: January 2007

This paper describes APL2/X, an interface between X-Windows and APL2, designed and built at the IBM Cambridge Scientific Center. It currently runs under VM/CMS and AIX. The APL2/X VM version of the interface uses the APL2 associated processor 11 to communicate with X. The APL2/X AIX version uses a new auxiliary processor, AP144, to achieve the same functionality.APL2/X enables all of the X-Windows Xlib calls and data-structures for use from the APL2 environment. In so doing, it enables APL2 to make use of a true windowing environment. Several APL2 sample programs using the interface have been coded to illustrate and validate the interface.The basic X-Windows Xlib is actually a large application written in C. APL2/X has therefore been built upon, as well as heavily influenced, a general APL2-to-C interface that runs on various platforms: APL2 under VM/CMS and MVS/TSO, APL2 for the RISC System/6000™ under AIX, and APL2/PC under PC/DOS.
Mastering J
Authors: McIntyre Donald B.
Published: January 2007

J is a new dialect of APL that provides much additional power over earlier dialects, and also provides a challenge to the user to master this new power. This paper discusses some of the problems the author encountered in learning J, and how they were overcome.
Feedback fault tolerance of real-time embedded systems
Authors: Liu Xue , Ding Hui , Lee Kihwal , Sha Lui , Caccamo Marco
Published: January 2007

Fault tolerance is an important aspect in real-time computing.In real-time systems, tasks could be faulty due to various causes. Faulty tasks may compromise the safety and performance of the whole system and even cause disastrous consequences. In this paper, we study the possibilities of applying feedback control of software execution to real-time systems for fault tolerance purposes. A new fault tolerance architecture called ORTGA (On-demand Real-Time GuArd) is proposed. We argue the advantages and benefits of using ORTGA for fault tolerance in real-time systems. We also list research problems faced by ORTGA and point out directions for possible solutions. Throughout the paper, we use an example of real-time inverted pendulum control to illustrate ideas, problems and and possible solutions.
The challenge metrication presents to managers of computer resources
Authors: Pokorney Joseph L.
Published: January 2007

This paper outlines the impending U. S. change to the metric measurement system. Using the recent NBS metric study and current legislation to establish the inevitability of the metric transition, the paper identifies those areas in which computer resources will be affected. The recent NBS study failed to examine the impact of metric conversion on existing computer systems and resources even though many potential problems exist in the areas of data field sizes, file design, file conversion, precision and accuracy. The paper explores these problem areas and identifies those steps alert managers can take to avoid major problems. The author presents this challenge as an opportunity to the data processing industry; an opportunity to take the lead and show users that we can perform in a professional manner. Because of the long lead time in systems development this problem must be tackled in the immediate future if we are to keep on top of it. No other country has been so dependent on computers when they went through a metric conversion; thus, we are on our own and must plan now for the metric transition and its impact on computer resources.
On managing interactive remote access computing
Authors: Grochow Jerrold M.
Published: January 2007

This paper will attempt to provide a framework for systematizing the management view of interactive remote access computer systems (IRACS). It will address a number of characteristics of these systems calling for increased management attention in comparison to batch systems and the traditional concerns of computer center management. User requirements for different levels of these characteristics will be discussed and possible trade-offs investigated. By high-lighting the significant differences between user, operational, technological, and organizational requirements of IRACS and those of batch systems, we hope to provide installation managers with a heightened sense of priorities both for operational decisions and for planning for new installations and new systems.In the area of user requirements, such issues as documentation, response time, and continuity of service will be investigated. Operational issues include maintainability, reliability, and control. Technological problems stemming from communications, storage, and reliability requirements will also be discussed. Finally, organizational areas such as system administration, complaint receipt, and user education will be given treatment.
Report on the ad-hoc track of the INEX 2005 workshop
Authors: Lalmas Mounia , Kazai Gabriella
Published: January 2007

The INitiative for the Evaluation of XML retrieval (INEX) has, since 2002, been working towards the goal of establishing an infrastructure, in the form of a large XML test collection and appropriate scoring methods, for the evaluation of content-oriented XML retrieval systems. In 2005, 47 organizations registered to participate in INEX. Throughout the year a number of groups dropped out due to resource requirements, while 11 further groups joined. INEX 2005 concluded with a total of 41 active groups. In addition to the main ad-hoc retrieval track, six further research tracks were included in INEX 2005, each studying different aspects of XML information access: interactive, relevance feedback, heterogeneous, natural language processing, and two new tracks for 2005, multimedia and document mining tracks.
Revenue recovering with insolvency prevention on a Brazilian telecom operator
Authors: Pinheiro Carlos André R. , Evsukoff Alexandre G. , Ebecken Nelson F. F.
Published: January 2007

This paper deals with a real application on a brazilian telephone company. Data mining analysis, based on neural networks, was performed on the customer base in order to understand and to prevent bad debt events. This paper describes the knowledge discovering process and focuses on two main products: the cluster analysis of the customer base and a bad debt event classification model. The segmentation of the customer base has provided a better understanding of several groups of customers' behavior. Distinct actions are taken, depending on the segment a given client was put in, according to strategic directions of the company. The classification of insolvent customers is used as a tool to help the company to take preventing actions in order to avoid main losses and taxes leakage. The results of the project's implantation show that investment on information technology infra-structure for data mining is highly profitable.
Evaluation of efficiency in a virtual memory environment
Authors: Steinhorst G. Cort , Bateman Barry L.
Published: January 2007

The development of elaborate supervisory systems for the modern day computer has dictated a need for a means of evaluating the efficiency of the computing system under normal operating conditions. This paper defines a set of synthetic job streams which can be used to evaluate the performance of virtual memory computing systems under batch program conditions. An illustration of the use of these synthetic streams is presented in an empirical search for the optimum batch limit of a specific example of a virtual memory computer system. Limited tests are also presented to support the results of this study.
On calibrating a computer system
Authors: Ford C. A.
Published: January 2007

A systematic method for evaluating the utilization rate of resources of a complex computer is described. The process presumes a large scale multiprogrammed system which experiences workloads in excess of throughput capacities for significant periods daily.The development follows from considerations of benchmarking and the nature of multiprogramming.The method was developed and exploited at the IBM S/370-165 installation at the University of Toronto. Details of the calibration system and quantitative results for a seven-month operational period are presented, including correlations with hardware monitor data.
Computing determinants of rational functions
Authors: Umeda Yasushi , Sasaki Tateaki
Published: January 2007

Computation of determinants of rational functions seems to be out of thought in computer algebra so far. We first show that representing the rational function by the sum of partial fractions is absolutely necessary in the computation. We then propose a very simple technique for efficient computation: replace every distinct denominator of the rational functions in the input matrix by the inverse of an independent variable, and recover the denominators after computing the determinant as a polynomial. Some experiments show that the technique speeds up the computation by 3 ~ 6 times for the samples tested.
Research trends in real-time computing for embedded systems
Authors: Buttazzo Giorgio
Published: January 2007

Most of today's embedded systems are required to work in dynamic environments, where the characteristics of the computational load cannot always be predicted in advance. Still timely responses to events have to be provided within precise timing constraints in order to guarantee a desired level of performance. Hence, embedded systems are, by nature, inherently real-time. Moreover, most of embedded systems work under several resource constraints, due to space, weight, energy, and cost limitations imposed by the specific application. As a consequence, efficient resource management is a critical aspect in embedded systems, that must be considered at different architecture levels.The objective of this document is to present the major research trends identified by the international community on real-time systems to make the next generation embedded systems more predictable and adaptive to environmental changes. After describing the characteristics of modern embedded applications, the paper presents the problems of the current approaches and discusses the new research trends in operating systems and scheduling emerging to overcome them.
Psychological research methods in the human use of computers (panel session)
Authors: Gould John D. , Anderson John A. , Barnard Phil
Published: January 2007

Psychological research methods have been used with increasing frequency in work on computer-human interaction. Judging from the state of the literature and from remarks heard in the halls at conferences such as this, the utility and appropriate roles of such methods are not yet clear. Panel members, who are all research psychologists working on issues related to human use of computers, will present a variety of contrasting views on how to go about such research, and on its proper goals. John Gould will describe two different but complimentary approaches, applied research on general design issues, and formative human factors participation in development. John Anderson will discuss the use of formal models of human cognition. Phil Barnard will consider the role of applied research in the discovery of underlying principles to guide design. Tom Landauer will propose that psychological research can be the basis for invention of new “;cognitive tools”. Short synopses of the positions they will take e given below. Panel members hope that the audience will join them in bringing out important differences between the various approaches and methods and arguing their absolute and relative merits.
Information sought and information provided
Authors: Pollack Martha E.
Published: January 2007

Transcripts of computer-mail users seeking advice from an expert were studied to investigate the complementary claims that people often do not know what information they need to obtain in order to achieve their goals, and consequently, that experts must identify inappropriate queries and infer and respond to the goals behind them. This paper reports on one facet of the transcript analysis, namely, the identification of the types of relation that hold between the action that an advice-seeker asks about and the action that an expert tells him how to perform. Three such relations between actions are identified:
generates, enables,
and
is-alternative-to
. The claim is made that a cooperative advice-providing system, such as a help system or an expert system, must be able to compute these relations between actions.
Intelligent help in a one-shot dialog
Authors: Aaronson Amy , Carroll John M.
Published: January 2007

A database of 150 interactions conducted via electronic mail was analyzed. The database had been constructed as an on-line tool for users and advisors, but the interactions can also be regarded as modelling intelligent help dialog in which posing a query and providing a response are each accomplished in “one-shot”. The types of questions users ask and the advisory strategies employed for imcomplete queries without follow-up questioning are described. The goal is to understand this new on-line tool for advising and its implications as a model of one-shot intelligent help dialogs.
Towards a model of user perception of computer systems response time
Authors: Geist Robert , Allen Robert , Nowaczyk Ronald
Published: January 2007

The foundational structure of a new model of user perception of computer system response time is proposed. It is suggested that the development of such a model is now of central importance to the computer system configuration design effort. The new model is seen to explain the success of an earlier measure, designed for the non-interactive environment, in predicting user estimates of response time for interactive systems. The results of new empirical studies, designed to delineate specific components of the model, are also discussed.
Transfer between text editors
Authors: Polson Peter G. , Bovair Susan , Kieras David
Published: January 2007

This paper describes a successful test of a quantitative model that accounts for large positive transfer effects between similar screen editors, between different line editors and from line editors to a screen editor, and between text and graphic editors. The model is tested in an experiment using two very similar full-screen text-editors differing only in the structure of their editing commands, verb-noun vs noun-verb. Quantitative predictions for training time were derived from a production system model based on the Polson and Kieras (1985) model of text editing.
Interface design: a neglected issue in educational software
Authors: Frye Douglas , Soloway Elliot
Published: January 2007

The user interface is particularly important for educational software because 1) it must provide an entry to the content domain of the program rather than vice versa and 2) it must be sensitive to the general skill and/or developmental level of the user. In spite of these special characteristics, interface design for educational software has been given little attention. This study evaluates a representative interface from arithmetic software now used in the schools. It was found that the interface caused students a large number of difficulties. These difficulties were sufficient to interfere with the instructional effectiveness of the software. Designing interfaces that will benefit educational software will require careful study of the users of these programs along with an in-depth understanding of the domains being taught.
The interface is often not the problem
Authors: Goransson Bengt , Lind Mats , Pettersson Else , Sandblad Bengt , Schwalbe Patrik
Published: January 2007

Computer systems in the form of tools for specific functions within a work environment are becoming increasingly common. Because the users are not computer experts, and because the introduction of the new tools can dramatically change their tasks, problems arise. It is argued that even if the proper design of the MMI is very important, this will not solve all the problems. More basic problems concern what functions should be included in the system and how the users can understand what the system can do in different work situations and how the response should be evaluated in the context of the work situations. This is demonstrated by experiences from application projects. It is concluded that more research must be devoted to these problem areas. Another important result is the fact that the possibilities to develop more generally applicable computer based tools are limited. Adaption to local circumstances and needs is usually a necessity.
Designing for designers: an analysis of design practice in the real world
Authors: Rosson Mary Beth , Maass Susanne , Kellogg Wendy A.
Published: January 2007

Twenty-two designers were interviewed about their design of interactive systems. They were asked to select a recent project having a significant user interface component, and were probed about the general design process involved, how the design of the user interface fit into that process, and their personal strategies for exploring ideas. Analysis of their responses pointed to two models of the design process. The relationship of these models to the type of user testing done and the strategies used for generating ideas is discussed, especially with respect to the implications for developing tools to support design.
Issues limiting the acceptance of user interfaces using gesture input and handwriting character recognition (panel)
Authors: Sibert John , Buffa Michael G. , Crane Hewitt D. , Doster Wolfgang , Rhyne James , Ward Jean Renaerd
Published: January 2007

Recently there has been increasing attention to character recognition/graphical user interfaces under the name of “gesture input”. This technique actually has a long history: “sketch recognition” interfaces of 15 or more years ago were highly praised [Applicon 73], and user interfaces using handwriting input before the wide use of text keyboards were one of the first research goals in computer science [Bledsoe 59]. The underlying character and symbol recognition technologies have been a major research area in their own right since the early 1950s [Suen 80].

The last two years have seen an upsurge in the number of developments in this area, both from commercial companies attempting to exploit new character and symbol recognition technologies, [CIC 85] [Pencept 84] [Cooper 82] and from researchers starting from fundamental questions in user interactions [Buxton 86] [Wolf 86]. However, one question still remains: “Why has this set of techniques had so little impact on user interface design practice, despite its long history and promise?” This panel discussion should give many answers to this question.

Panelists include the leading commercial developers of handwriting input products, well-known researchers in the psychological aspects of graphical user interactions, and representatives of the research community for character recognition.

The issue of supporting this type of interface is very timely: recent standardization efforts such as PHIGS and GKS for graphics interactions are known to have the unfortunate side effects of excluding some of the current user interface designs using this class of technology [10].
Eliminating distinctions of class
Authors: Hutchins DeLesley
Published: January 2007

In mainstream OO languages, inheritance can be used to add new methods, or to override existing methods. Virtual classes and feature oriented programming are techniques which extend the mechanism of inheritance so that it is possible to refine nested classes as well. These techniques are attractive for programming in the large, because inheritance becomes a tool for manipulating whole class hierarchies rather than individual classes. Nevertheless, it has proved difficult to design static type systems for virtual classes, because virtual classes introduce dependent types. The compile-time type of an expression may depend on the run-time values of objects in that expression.We present a formal object calculus which implements virtual classes in a type-safe manner. Our type system uses a novel technique based on prototypes, which blur the distinction between compile-time and run-time. At run-time, prototypes act as objects, and they can be used in ordinary computations. At compile-time, they act as types. Prototypes are similar in power to dependent types, and subtyping is shown to be a form of partial evaluation. We prove that prototypes are type-safe but undecidable, and briefly outline a decidable semi-algorithm for dealing with them.
Design fragments make using frameworks easier
Authors: Fairbanks George , Garlan David , Scherlis William
Published: January 2007

Object oriented frameworks impose additional burdens on programmers that libraries did not, such as requiring the programmer to understand the method callback sequence, respecting behavior constraints within these methods, and devising solutions within a constrained solution space. To overcome these burdens, we express the repeated patterns of engagement with the framework as a
design fragment
. We analyzed the 20 demo applets provided by Sun and created a representative catalog of design fragments of conventional best practice. By evaluating 36 applets pulled from the internet we show that these design fragments are common, many applets copied the structure of the Sun demos, and that creation of a catalog of design fragments is practical. Design fragments give programmers immediate benefit through tool-based conformance assurance and long-term benefit through expression of design intent.
Efficient control flow quantification
Authors: Bockisch Christoph , Kanthak Sebastian , Haupt Michael , Arnold Matthew , Mezini Mira
Published: January 2007

Aspect-oriented programming (AOP) is increasingly gaining in popularity. However, the focus of aspect-oriented language research has been mostly on language design issues; efficient implementation techniques have been less popular. As a result, the performance of certain AOP constructs is still poor. This is in particular true for constructs that rely on dynamic properties of the execution (e.g., the
cflow
construct).In this paper, we present efficient implementation techniques for
cflow
that exploit direct access to internal structures of the virtual machine running an application, such as the call stack, as well as the integration of these techniques into the just-in-time compiler code generation process.Our results show that AOP has the potential to make programs that need to define control flow-dependent behavior not only more modular but also more efficient. By making means for control flow-dependent behavior part of the language, AOP opens the possibility of applying sophisticated compiler optimizations that are out of reach for application programmers.