bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling medical diagnosis of headache, brain strokes and congential malformation
Authors: Tsumoto Shusaku
Published: January 2007

One of the important problems of knowledge discovery in medicine is the comprehensibility of knowledge extracted from databases. This project aims at modeling medical experts' diagnosis and inducing rules similar to the experts, which makes induced results easy to interpret. Rough set based rule induction methods are applied to clinical databases on differential diagnosis of headache, brain strokes and congenital malformation. Experimental results show that knowledge which medical experts implicity use for their differential diagnosis are extracted in more explicit ways and several kinds of knowledge which experts did not expect were extracted.
Knowledge discovery in perioperative databases
Authors: Waitman Russ
Published: January 2007

Knowledge Discovery in Perioperative Databases: Hypothesis Testing, Decision Support, and Care Pathway Assessment. Previously merged C4.5 with expert guided inductive learning. Currently researching the use of BRUTE force induction to discover relationships in perioperative data. Will be analyzing physiological data from patients in the operating room as well as information contained in a perioperative database.
Data mining applied to data on respiratory effects of air pollution
Authors: Lamers Maarten
Published: January 2007

Aim of the projects is the investigation and development of techniques for dealing with specific aspects of health-related data in epidemiological studies. Non-linear neural network data-mining methodologies were successfully devised for• finding heterogeneity in response between unknown subpopulations in a study;• reducing non-linear correlations between related bio-medical variables;• testing for non-linearity of responses in multi-level population studies.Applications to data from studies on short-term respiratory effects of air-pollution have illustrated the merits of these methods when complementing traditional methods.
WizWhy
Authors: Meidan Abraham
Published: January 2007

We have developed a new association rules algorithm, that is used not just for revealing all the if-then rules, but for issuing predictions as well. This algorithm avoids the problem of overfitting by calculating the error probability of each rule. Our package, WizWhy for Windows 95/NT, that is based on this algorithm is used in many biomedicine research groups.
Per-queue stability analysis of a dynamic quota sharing scheme for wireless networks
Authors: Lam Sum , Chang Rocky K. C.
Published: January 2007

In this paper we consider a dynamic quota sharing scheme to support different classes of data traffic in wireless networks. The novelty of this scheme enables the lower-priority classes of traffic to use what has not been used by the higher-priority classes. We have performed per-queue stability analysis for this scheme. Based on the stability results, threshold values can be appropriately determined to fulfill certain throughput requirements.
An overview of Knowledge Representation
Authors: Mylopoulos John
Published: January 2007

This is a brief overview of terminology and issues related to Knowledge Representation (here-after KR) research, intended primarily for researchers working on Semantic Data Models within Database Management and Program Specifications within Programming Languages/Software Engineering.

Knowledge Representation is a central problem in Artificial Intelligence (AI) today. Its importance stems from the fact that the current design paradigm for “intelligent” systems stresses the need for expert knowledge in the system along with associated knowledge-handling facilities. This paradigm is in sharp contrast to earlier ones which might be termed “power-oriented” [Goldstein and Papert 77] in that they placed an emphasis on general purpose heuristic search techniques [Nilsson 71].
Dynamic system specification
Authors: Balzer Robert M.
Published: January 2007

Our group is perhaps unique in that our approach to modeling dynamic systems has a strong heritage from all three fields represented at this workshop. Each of the fields has contributed four major concepts to our modeling approach.

From the Data Base field, we have adopted the idea of a single global model (data base) which defines the state of the system. Fully associative relations among typed atomic objects (no internal structure) constitute the entire state description. An information model (query language) is defined for extracting information from the state (such as one or all objects satisfying some description, or the truthfulness of some proposition). Finally, the model is updated via transactions, so that either the entire operation is completed successfully, or the state is unchanged.
Some contrasts and considerations of an approach to modelling
Authors: Feather Martin S.
Published: January 2007

We consider the approach to modelling that our group has been developing, first to highlight differences between this and the approaches of other researchers, second to raise some issues related to understandability of models that we feel are common to modelling in general. The principles underlying our approach may be found in Balzer's position paper to this workshop.
Heterogeneous databases and high level abstraction
Authors: Katz Randy H.
Published: January 2007

A heterogeneous database management system combines multiple dissimilar models of data within a single integrated system. The objective is to allow a user to access data independently of how it is actually organized. For example, a user may access a database as though it were stored relationally (i.e., in tables) [CODD70], even though it is actually stored as a CODASYL/DBTG or network database [CODA71]. In addition, different subpieces of the database may be organized under different data models. The heterogeneous database system must present these to the user as an integrated whole. The user's model of his data may be different from any of the models chosen to implement it.

Rather than construct a new database system from scratch, we are interested in constructing a heterogeneous system out of existing systems. The key difficulties with this approach are: (1) the formulation of database design methods that are applicable to a variety of different data models, and (2) the development of techniques to translate programs and data between dissimilar data models. In this paper, we briefly describe how high level abstraction has been applied to these problems. The use of abstraction in database systems is related to the application of abstraction techniques in programming languages and artificial intelligence research.
Modelling concepts for reasoning about access to knowledge
Authors: King Jonathan J.
Published: January 2007

There is growing agreement about the usefulness of putting semantic database constraints into explicit form that can be manipulated by various database management programs. Indeed, this is a prerequisite for building
intelligent database mediators
. These are programs that perform the task of a good database analyst: to pose the most effective and easily processed queries to help solve a problem.
Semantic query optimization
is a technique to exploit semantic constraints for one aspect of intelligent database mediation: increasing retrieval efficiency. The technique is to use semantic constraints to transform a query into an equivalent one that can be processed more efficiently. Various kinds of semantic knowledge that can be used for this purpose are described.
Relativism and views in a conceptual data base model
Authors: Kreps Peter
Published: January 2007

The purpose of the Pingree Park Workshop was to bring together practitioners from the fields of Artificial Intelligence (AI), Database Management (DB), and Programming Languages (PL), to discover common issues, and to explore commonalities and differences in approaches to these issues. At the risk of being superficial let me try to summarily characterize the three fields and point to where I think they may fruitfully interact.

It seems to me that at its best, AI is an interdisciplinary science of cognition. It attempts to understand the bases for natural cognition, primarily by developing models of structures and processes that underlie cognition. By incorporation into interactive systems these models can be both exploited as artificially intelligent technology and explored for their adequacy in explaining natural cognition.
Incompleteness in knowledge bases
Authors: Levesque Hector J.
Published: January 2007

The first topic for discussion at the High Level Abstraction Workshop was

What should be modelled?

that is, what aspects of the world (slice of reality / enterprise) must be dealt with in a high level conceptual model. I would like to address this question from the point of view of incomplete knowledge bases. Although my remarks pertain mainly to AI applications, I suspect that any application using an information system of some sort will eventually have to face similar issues.

The knowledge bases required in many applications can be characterized by a lack of complete information about the world of interest.
A three-level approach to the description of data structures, and notational framework
Authors: Meyer Bertrand
Published: January 2007

When talking about data structures, whether local to a program or persistent over time, three different viewpoints are equally important. The first one is that of the user, who is interested in the external properties of a certain structure, more precisely, its noticeable behavior in response to outside effects (queries, requests for modifications, etc.). The second viewpoint is that of the language designer, who is in search of a small number of basic objects and building mechanisms which will allow for the description of complex objects in terms of simpler ones. The last view is that of the implementor, who must find efficient representations for the constructs thus described.

Based on this remark, a three-level description of data structures has been used by the author in previous work [6, 7, 8]. The three levels may be called:
A perspective for research on conceptual modelling
Authors: Mylopoulos John
Published: January 2007

This position paper is intended to provide a perspective for research on conceptual modelling carried out over the past five years at the University of Toronto and to draw some conclusions from the experiences we have accumulated. “Conceptual modelling” here refers to the activity of constructing abstract models of knowledge about some world and is synonymous with the terms “knowledge representation” and “semantic data model” as they have been used in AI and Databases respectively. Much of the research on the subject has focused on the development of descriptive tools for the description of such models. Less attention has been paid, so far, on methodologies for building such models.
Abstract data types and Data Bases
Authors: Paolini Paolo
Published: January 2007

Several researchers have been working, recently, at the attempt of using the ADT approach in the Data Base area. Different specific problems have attacked and we will review some of them.
Data bases
Authors: Reiter Raymond
Published: January 2007

My work in data base theory is a natural outgrowth of my longstanding concern with the problem of representing and reasoning with domain specific knowledge, a problem of major concern in Artificial Intelligence. In data base terminology this is the conceptual modelling issue. My own methodological bias favours logic as a representation language for conceptual modelling, a bias which historically arose within AI in response to AI's emphasis on the ability to reason deductively with representations. In this position paper I shall argue that logic has other advantages for data base theory. Specifically my objective is to provide the outline of a logical reconstruction of certain aspects of conventional data base theory.
Secure sharing of location information over Ad hoc networks
Authors: Noubir Guevara , Lin Guolong , Golitsine Mikhail , Plante Nick
Published: January 2007

In this paper we address the problem of secure multicast of data streams over a multihop wireless ad hoc network. We propose a key management protocol that aims at solving problems that are specific to ad hoc networks such as mobility, unreliable links, and multihop communication cost. The main idea is to have group members actively participate to the multicast group security therefore reducing the communication and computation load on the source. We also extend the proposed basic secure multicast tree using multi-link capability combined with a k-out-of-N coding approac. Since the group security is distributed among the group members we propose a service right certificate to verify that a node is authorized to join the group and also corresponding revocation mechanism. We simulated our protocol within the ns-2 environment under various mobility, group size, and group dynamic scenarios. Our preliminary simulation results indicate that the communication cost and join delay of the protocol scale well when the group size and nodes mobility increase.
Automatic translation into French Grade 2 Braille
Authors: Truquet Monique
Published: January 2007

I would like to speak on the following subjects. How to translate texts into Braille with only a typist who doesn't know Braille rules.Difficulties encountered: codes of letters with accents and Braille signs. They have been studied when we worked for Braille Grade I.To obtain Braille Grade 2 we use a syntactical analyser, a "hashing" table and a "contraction" program.It seems that this last program can be used for other languages and it is this one that we shall study.
Modified standard office equipment for Braille translation and embossing
Authors: Loeber N. C.
Published: January 2007

Either inkprint or braille can be produced with an IBM Magnetic Card SELECTRIC (R) Typewriter equipped with a read-only translation circuitry and an embosser. Embossing is done on the front side of the paper so the operator can read the information as it is embossed. Information entered at the standard keyboard and recorded on a magnetic card can be played back in both inkprint and braille. The same embosser may be used on other machines with removable type balls, such as the IBM 2741 Communication Terminal Communication Terminal.
On imaginary fields, token transfers and floating codes in intelligent secondary memories
Authors: Lipovski G. J.
Published: January 2007

In analyzing two implemented intelligent secondary memories, CASSM and RAP, we recognize a common mechanism which is here called an imaginary field. The mechanism can be generalized to suggest further design possibilities. It further explains the complex and controversial CASSM mechanism, “pointer transfer” in terms of separate but related principles—imaginary fields, token transfers, and floating codes—such that further designs can utilize some or all of the techniques.
Ulisse
Authors: Cerretti R. , Jasilli D. , Matteucci D. R.
Published: January 2007

The paper describes a project conducted in collaboration between CNUCE, an Institute of the Italian National Research Council, and a private research center, concerning a multifunctional system (Ulisse) capable of operating both as a stand alone unit for office administration and automation (word processsing, file management and retrieval) and as an intelligent terminal with local facilities for text editing, text formatting and storage.

The first results of the application of Ulisse in the environment of the scientific users of CNUCE are illustrated.
J2EE infrastructure scalability and throughput estimation
Authors: Brebner Paul , Gosper Jeffrey
Published: January 2007

ECperf, the widely recognized industry standard J2EE benchmark, has attracted a large number of results submissions and their subsequent publication. However, ECperf places little restriction on the hardware platform, operating systems and databases utilized in the benchmarking process. This, combined with the existence of only two primary metrics, makes it difficult to accurately compare the results, or the performance of the Application Server products themselves. By mining the full-disclosure archives for trends and correlations we have discovered that J2EE technology is very scalable with increasing middle-tier resources, as long as the database has sufficient resources to prevent it becoming a bottleneck. Other observed trends include, a linear correlation between middle-tier total processing power and throughput, as well as between J2EE Application Server license costs and throughput. However, the results clearly indicate that there is an increasing cost per user with increasing capacity systems. Finally, the correlation between middle-tier processing power and throughput, combined with results obtained from a different 'lighter-weight' benchmark, facilitates an estimate of throughput for different types of J2EE applications.
Nonce functions
Authors: Benkard J. Philip
Published: January 2007

Data, functions, and operators exist in divers current APL systems in primitive, derived, and defined forms. Only data primitives occur in an extended literal form, which can be quite complex. This paper introduces a form of function literal, subsequently extended to include operators. Lexical scope is restricted to the minimum to achieve perspicuousness and syntactic predictability. The short expressions which result form convenient, explicit representations of some common trivial functions. They can indirectly simulate trivial operators. Nonce operators can simulate syntactic entities, which have been called transforms, that produce operators. The trade-offs between extra key strokes and symbol clutter are discussed.
APL as the foundation for a universal computer language
Authors: Dunwell Stephen W.
Published: January 2007

Some ways in which universal computer languages differ from those in common use today. Universal dictionary. Universal alphabet. Universal character representation. Universal keyboard. Universal communication among computer systems. Elimination of an operating system as a separate entity.

Some advantages of universal computer languages over those in common use today. Easier to teach and to learn. Easier and faster creation and modification of software. Faster execution. Easier transfer of software from one system to another. Fewer application software packages required.

Some of the changes and additions required to make APL an acceptable universal computer language. Implement the APL interpreter at the chip level. Add language features to meet operating system requirements. Eliminate the features now required to communicate with operating systems of the present kind. Improve communication among users of a system. Improve the handling of integers. Improve the handling of graphics. Improve alphabet, character representation, and keyboard.

The second edition of my monograph on this subject will be available at the Copenhagen APL Conference.
A structured approach to analysis and design of complex systems
Authors: Evans F. , Jantzen J.
Published: January 2007

An automatic control system for managing the heating of a modern building may involve several thousands of components and feedback loops. As such systems grow, decomposition into (nested) subsystems becomes increasingly necessary.

The subject of the poster session is complexity in large scale systems.

We think we can make the computer manage the complexity in any system that can be described in a block-diagram.

A variety of complex systems are represented by different types of block-diagrams. They have one theoretical concept in common: connectedness. Directed graphs (digraphs) can describe the fundamental concepts of structure and reachability, and graph theory provides a consistent mathematical theory of it.

The South Bank Polytechnic and the Technical University of Denmark are actively concerned through industrial collaborators with problems of

energy management for modern buildings

control of waste water in urban sewage networks

fuzzy control of industrial processes

engineering management systems

expert system design for fault diagnosis and food poisoning diagnosis.

All these problems require a tool for i) inputting and editing of graphs, and ii) an executable, array based model.

In the late 70'ies Franksen, Falster & Evans (1979) proposed a description of control systems based on a Boolean array representation of digraphs. At APL87 Fordyce & Sullivan presented an inference mechanism for VLSI chip manufacturing, also based on Boolean array structures (Fordyce & Sullivan, 1987). The APL89 conference had a similar nested array approach (Jantzen, 1989), and recently, the beginning of a whole theory, based on the 'digraph approach' has been published (Reinschke, 1988).

The poster session will present a digraph model, in which the nodes contain tree-structured, nested data. The oriented arcs display the flow of information. Internally each level of the diagram will be stored in a nested array. The user can draw the diagram directly on screen using a digitizer.

The session will include live demonstrations of

fault diagnosis on a water tank model of a sewage network

a structured approach to expert system design

interactive graphics for object oriented visual programming (APL2)

frame based data systems (APL2).

The demonstrations will emphasize the PC, PS/2 and RT/PC based aids to complexity management.

The digraph approach promises speed and space gains due to the purely Boolean array representations, as well as user-friendliness due to automatic decomposition techniques.
Editing and debugging with Windows and a mouse
Authors: Foster Garth H. , Elgouri Abdelatif , Liu Franklin
Published: January 2007

This paper describes how full screen editing and debugging using a mouse and windows can be added to the APL2/PC programming environment. The use of AP124 and a special purpose auxiliary processor to support windowing are described.
Color APL beautiful!
Authors: Fox Ralph L.
Published: January 2007

This paper presents many ways you can use color display attributes to make your interaction with the APL*PLUS PC and APL*PLUS II Systems more productive and enjoyable. An extensive suite of utility functions will be illustrated. These functions enable you to establish color schemes for the editing, maintenance, and display of functions and many types of data arrays. The workspace of utilities, many of which are also applicable to monochrome monitors, is publicly available in several formats.
An application development platform
Authors: Kromberg Morten , Gfeller Martin
Published: January 2007

While APL was a highly productive system for personal computing and application development when it was introduced, it is lacking nowadays in the areas of programming-in-the-large and user interface construction.

The design and implementation of a new Application Development Platform (ADP) is described. The ADP frees the programmer from user interface concerns, and frees the application from device specific code. The ADP ensures consistent user interfaces based on state-of-the-art window techniques.

Together with the underlying APL language, a software repository (Logos) and a data handling facility (ViewPoint®) the ADP is part of a full application environment.

The paper describes the underlying principles of our ADP. We also present a small worked out example comparing a traditional toolbox with the ADP.
Desktop publishing on the mainframe: integrating APL2 and Ventura Publisher
Authors: Laurmaa Timo
Published: January 2007

This paper
1
describes a facility that enables APL applications to be provided with high-quality output via integration of the mainframe
APL 2
environment and a PC desktop publishing system. The facility is a combination of mainframe and PC applications, in which the mainframe transmits data to be efficiently processed in a PC.
A preferable look—APL in window-based environments
Authors: Recker Ursula , Rys Michael
Published: January 2007

Currently, most APL systems are line and workspace oriented. It will be shown how a modern APL could fit into a window-based, event driven environment. To achieve this goal, a future user interface in an experimental environment is sketched by presenting its language environment, the editor and the debugging facility.
What's ahead for 2000 A.D.?
Authors: Smith Howard J.
Published: January 2007

On January 1, 2000 many applications will stop working properly. Most utilities and applications express the year as the two low order digits of the full representation of the year so that dates in the new century will appear to occur before dates in the old. When this phenomenon occurred in the past humans adapted quickly, and no great dislocation occurred.

Unfortunately, the computer is not as adaptable or reasonable as the human.

This paper presents one possible solution to the problem, at least in the APL environment. This solution involves replacing date fields in files and records with a pseudo-Julian day number (PJD). This number permits the analyst to use date information arithmetically to determine the day of the week, the period between dates, create lists of dates, etc. The PJD is easily converted to or from human-usable canonical date forms. Finally, the technique defers difficulties due to changes of year, century, millennium, etc. indefinitely.

In the later sections of the paper some thoughts on possible extensions to the leap-year algorithm are discussed. The new terms would improve precision without affecting the past or present. Finally, sample functions which support and utilize this “perpetual” calendar are given.

It must be emphasized that this paper represents a solution only within the APL environment. The concept is applicable in any environment, language or system but only if it or a similar solution is adopted before December 31, 1999. If we users of APL recognize and fix the problem in our environment while the rest of the computing world ignores it, the problem will still affect everyone, including us.
Stability in a sea of change
Authors: Soule Danald
Published: January 2007

As a developer, how do you continue to productively develop business applications when the hardware/software environment changes twice each year?
LYYTI—integrated design and control system
Authors: Teileri Timo , Olkkola Toivo
Published: January 2007

LYYTI is an APL2-based integrated system for design and manufacturing of customer-tailored switchgears, consisting of some expert system features. System development started year 1981. LYYTI system uses relational database DB2 and has interfaces to FORTRAN, GDDM and CADAM (via FORTRAN). Lyyti is used in mainframe IBM 3090-180S under TSO and all of the c. 120 daily users use the same packaged work space. (Transferring into PC-PS/2 network system is under development on winter 1990).
FRESH, an expert system design tool on APL2
Authors: Vermeulen J. W. B. , Spoor E. R. K.
Published: January 2007

The emergence of commercially available expert system shells has opened up new avenues for large scale development of expert systems. However, this challenge also generates a new problem area concerned with ways of integrating such developments with existing information modelling environments. Expert system shells and conventional systems originate from distinct research areas with mutually differing modelling-views. These differences retard the natural incorporation of the new technology in existing environments.

To attack this problem, a migration path is required. The fundamentals of expert systems shells should be carefully grafted upon existing modelling views in order to bridge the gap.

This contribution describes the expert system design tool FRESH (Frame Relationship Expert-system SHell) and its underlying principles. The fundamentals of FRESH closely resemble those of the Entity-Relationship (ER) approach to information modelling. Some necessary adjustments, which enable knowledge representation, fit in naturally, without having the modelling view drift away from its origin.

FRESH has been implemented in APL2, exploiting the language's state of the art data structures and interactive capabilities. Also, APL2 provides excellent opportunities to interface expert system technology to traditional management information systems.
A novel route update design for wireless sensor networks
Authors: Hu Xuhui , Liu Yong , Lee Myung J. , Saadawi Tarek N.
Published: January 2007

In wireless sensor networks, mobility of targets and sinks, as well as power exhaustion of sensors often leads to breakage of existing routes. In this paper, we propose an efficient route update protocol (ERUP) to rebuild new routes in the neighborhood of broken ones. ERUP consists of two steps: firstly, nodes along the old problematic route define a packet propagation region; and then, route rediscovery packets are broadcast only within this region. ERUP not only achieves very low control overhead, but also provides much bigger freedom for the selection of new routes, which unnecessarily overlap the old ones. This virtue is especially important to the route-wide update cases, such as continuous movement of endpoints, and renovation of worn-out routes. Simulations verify the efficiency and scalability of ERUP.
Modeling and analyzing the impact of location inconsistencies on geographic routing in wireless networks
Authors: Kim Yongjin , Lee Jae-Joon , Helmy Ahmed
Published: January 2007

Recently, geographic routing in wireless networks has gained attention due to several advantages of location information. Location information eliminates the necessity to set up and maintain explicit routes, which reduces communication overhead and routing table size. These advantages allow scalability especially in dynamic and unstable wireless networks. However, no matter which technologies or techniques a location system uses, its measurements will have some amount of quantifiable inaccuracy depending on environment and system. These inaccuracies may affect the performance and even correctness of geographic routing. However, thus far, these impacts have not been studied in-depth. In this paper, we analyze the impact of location inaccuracy on geographic routing. First, we model location inaccuracy metrics - absolute location inaccuracy, relative distance inaccuracy, absolute location inconsistency and relative distance inconsistency. Then, we analyze how location inaccuracy metrics affect the building blocks of geographic routing including greedy forwarding and local maximum resolution. We use extensive NS-2 simulations to evaluate the performance of geographic routing using a wide array of parameter settings including inaccuracy level, node degree and network diameter. In our simulation results, reasonable location inaccuracy (of 20 percent or less of radio range) caused packet drop reaching up to 54 percent, non-optimal path up to 53 percent and packet looping. These observations indicate the importance of re-visiting geographic routing protocols, and the significance of considering location inaccuracy in their design and evaluation.
A comparison of methods for accurate summation
Authors: McNamee John Michael
Published: January 2007

The summation of large sets of numbers is prone to serious rounding errors. Several methods of controlling these errors are compared, with respect to both speed and accuracy. It is found that the method of "Cascading Accumulators" is the fastest of several methods. The Double Compensation method (in both single and double precision versions) is also perfectly accurate in all the tests performed. Although slower than the Cascade method, it is recommended when double precision accuracy is required. C programs that implement both these methods are available in the BULLETIN online repository.
MATCONT
Authors: Dhooge A. , Govaerts W. , Kuznetsov Yu. A.
Published: January 2007

We consider generic parameterized autonomous ODEs of the form
dx
/
dt
≡ ẋ = f(x, α), where x ∈ ℝ

n

is the vector of
state variables
, α ∈ ℝ

m

represents
parameters
, and f(x, α) ∈ ℝ

n

. There are several interactive software packages for analysis of dynamical systems defined by ODEs. The most widely used are AUTO86/97[1], CONTENT[2] and XPPAUT.The Matlab software package MATCONT provides an interactive environment for the continuation and normal form analysis of dynamical systems. This analysis is complementary to the simulation of the systems which is also included in the package and can be used in their identification, control, and optimization. MATCONT is designed to exploit the power of Matlab. It is developed in parallel with the continuation toolbox CL_MATCONT, a package of Matlab routines that can be used from the command line.We consider the following model of an autonomous electronic circuit where
x, y
and
z
are state variables and β,γ,ν,
r
,
a
3
,
b
3
are parameters: [see pdf for formula]We compute a branch of equilibria with free parameter ν stating from the trivial solution
x
= 0.00125,
y
= -0.001,
z
= 0.00052502 at
β
= 0.5, γ = -0.6,
r
= -0.6,
a
3
= 0.32858,
b
3
= 0.93358, ν = -0.9, ε = 0.001. We start a curve of periodic orbits from a Hopf point on this curve choosing ν as the free parameter. We detect a torus bifurcation point at ν = -0.59575. We continue the torus bifurcation in two parameters ν, ε and find that it shrinks to a single point for decreasing values of ν (Figure 2).
Using Fermat to solve large polynomial and matrix problems
Authors: Lewis Robert H.
Published: January 2007

Fermat
is an interactive system for mathematical experimentation. It is a super calculator - computer algebra system, in which the basic items being computed can be rational numbers, modular numbers, finite fields, multivariable polynomials, rational functions, or polynomials modulo other polynomials.In
Fermat
the default "ground ring"
F
is the field of rational numbers. One may choose to work modulo a specified integer
m
, thereby changing the ground ring
F
from

Q

to

Z

/m. On top of this may be attached any number of symbolic variables
t
1
,
t
2
, . . .,
t
n
, thereby creating the polynomial ring
F
[
t
1
,
t
2
, . . .,
t
n
] and its quotient field, the field of rational functions, whose elements are called
quolynomials
, Further, polynomials
p
,
q
, . . . can be chosen to mod out with, creating the quotient ring
F
(
t
1
,
t
2
, . . .) / <
p
,
q
, . . .>, whose elements are called
polymods
. If this is done correctly, finite fields result. Finally, it is possible to allow
Laurent polynomials
, those with negative as well as positive exponents. Once the computational ring is established in this way, all computations are of elements of this ring.
Fermat
has extensive built-in primitives for array and matrix manipulations, such as submatrix, sparse matrix, determinant, minors, normalize, column reduce, reduced row echelon, matrix inverse, Smith normal form, and characteristic polynomial. It is consistently faster than some well known computer algebra systems - orders of magnitude faster in some cases.
Fermat
is a complete programming language. Programs and data can be saved to an ordinary text file that can be read during a later session or read by some other software system.
Fermat
has solved real problems that other computer algebra systems could not. It is more efficient in both time and space. These problems have come from algebraic topology, group theory, image processing, computational geometry, decision theory, and signal processing.Most recent applications involve solving systems of polynomial equations with the
Dixon Resultant
technique. I will demonstrate this method at the conference, in particular how I attack the
spurious factor problem
.
Fermat
is available for Windows95/98/NT/etc and Mac OS. Fermat for Linux is ready for beta testing.
A Matlab package computing polynomial roots and multiplicities
Authors: Zeng Zhonggang
Published: January 2007

MULTROOT is a collection of Matlab modules for accurate computation of polynomial roots, especially roots with high multiplicities, using standard machine precision. As a blackbox-type software, MULTROOT requires the polynomial coefficients as the only input, and outputs the computed roots, multiplicities, backward error, estimated forward error, as well as the pejorative condition number.There are two common limitations for standard numerical root-finding software when multiple roots are present. Namely, those methods suffer from severe loss of accuracy and lack the capacity of multiplicity identification. Symbolic polynomial factorization requires
exact
rational coefficients. In contrast, the most significant features of MULTROOT are the multiplicity identification capability and the remarkable accuracy on multiple roots without using the multiprecision arithmetic, even if the polynomial coefficients are inexact.There is a so-called "attainable accuracy" for conventional root-finders: the attainable number of corrected digits of a computed root is limited by the data/machine precision divided by the multiplicity. For roots with high multiplicities, this accuracy barrier suggests that multiprecision arithmetic is required in addition to exact coefficients. Using a novel approach based on the pejorative manifold theory, MULTROOT achieves high accuracy even if the polynomial is perturbed and the machine precision is not extended. A stable numerical polynomial GCD-finder is also developed as an essential component that determines the multiplicity structure.MULTROOT is a combination of two programs that can be used independently. GCDROOT calculates the multiplicity structure and initial root approximation. PEJROOT refines the root approximations by projecting the polynomial onto a prescribed pejorative manifold. A comprehensive test suit of polynomials that are collected from the literature is included for numerical experiments and performance comparison.The detailed algorithm and analysis is presented in this conference [1].
Citation prediction using time series approach KDD Cup 2003 (task 1)
Authors: Manjunatha J. N. , Sivaramakrishnan K. R. , Pandey Raghavendra Kumar , Murthy M Narasimha
Published: January 2007

In this article we describe our experiences in building the winning system for KDD Cup, 2003, Task 1. This year's competition was based on a very large archive of research papers that provides an unusually comprehensive snapshot of a particular social network in action; in addition to the full text of research papers, it includes both explicit citation structure and partial data on the downloading of papers by users. It provides a framework for testing general network and usage mining techniques, which can be explored via four varied and interesting tasks. Each task is a separate competition with its own specific goal. In task 1 the goal is to predict the change in number of citations to each paper in the archive over time.The contest was very challenging because the given data was not in a format suitable for conventional data mining techniques. So we had to do a considerable amount of data processing. Also there were different sources of data like tex files, citation graph, slac-data database. So we had to make a decision about which sources to use and how much to use.
A multiprocessing system for the direct execution of LISP
Authors: Williams Rhon
Published: January 2007

Current implementations were found to be impractical for airborne use due to LISP's incompatability with conventional computer architectures. Direct execution of LISP with tasks distributed between three processors, seemed to be a workable solution. The language was analyzed, and a special token was devised, using a descriptor with a single pointer. Through careful distribution of responsibilities, control and data flow between the processors was minimized. Significant memory savings resulted from ASCII storage and real time garbage collection. A simulation was used to help estimate execution times and showed a factor of 50 to 100 increase in speed. Thus, through the direct execution of LISP by a multiprocessing system, Computer-Aided Decision-Making could be implimented to enhance the safety of flight operations.
The use of a database machine for supporting relational databases
Authors: Banerjee Jayanta , Hsiao David K.
Published: January 2007

One of the goals in the design of database machines of the future is their generality. In addition to being capable of carrying out the common database management functions with high reliability and performance, some of these machines are intended to support more than one data model. A specific database machine, known as the DBC, is intended to support several existing data models. Although the DBC supports many data models, we single out the relational data model for this discussion. In particular, we have tried to concentrate mainly on the subject of database representation and query translation of System R-like database management systems. Some estimates of the storage requirements and performance gains are given in this paper. However, due to limited space, the detailed analysis is shown elsewhere in [22].
Exploiting parallelism in a Relational Associative Processor
Authors: Sadowski Paul J. , Schuster S. A.
Published: January 2007

The Relational Associative Processor (RAP) is a special purpose non-numeric back-end processor used in supporting general Data Base Management Systems. In particular, it is ideally suited for supporting a relational data base. The architecture and instruction set of RAP are discussed in this context. It is the purpose of this paper to show that RAP performance can be enhanced considerably by more fully exploiting its parallel nature. It is shown that a greater degree of concurrent activity will result in better overall performance. An operating system executive to support this high level of concurrency is proposed and modelled using simulation techniques. Both the analytic and simulation results support the value of the proposals.
Blocking: exploiting spatial locality for trace compaction
Authors: Agarwal Anant , Huffman Minor
Published: January 2007

Trace-driven simulation is a popular method of estimating the performance of cache memories, translation lookaside buffers, and paging schemes. Because the cost of trace-driven simulation is directly proportional to trace length, reducing the number of references in the trace significantly impacts simulation time. This paper concentrates on trace driven simulation for cache miss rate analysis. Previous schemes, such as cache filtering, exploited temporal locality for compressing traces and could yield an order of magnitude reduction in trace length. A technique called
blocking
and a variant called
blocking with temporal data
are presented that compress traces by exploiting spatial locality. Experimental results show that blocking filtering combined with cache filtering can reduce trace length by nearly two orders of magnitude while introducing about 10% error in cache miss rate estimates.
Traffic characterization of the NSFNET national backbone
Authors: Heimlich Steven A.
Published: January 2007

Traditionally, models of packet arrival in communication networks have assumed either Poisson or compound Poisson arrival patterns. A study of a token ring local area network (LAN) at MIT [5] found that packet arrival followed neither of these models. Instead, traffic followed a more general model dubbed the “packet train,” which describes network traffic as a collection of packet streams traveling between pairs of nodes. A packet train consists of a number of packets travelling between a particular node pair.

This study examines the existence of packet trains on NSFNET, a high speed national backbone network. Train characteristics on NSFNET are not as striking as those found on the MIT local network; however, certain protocols exhibit quite strong train behavior given the great number of hosts communicating through the backbone.

Descriptions of the packet train model can be found in [3] and [5].
International symposium on symbolic and algebraic computation poster abstracts 2003
Authors: Caprotti Olga
Published: January 2007

ISSAC 2003 was held on July 3--6, 2003 at Drexel University in Philadelphia, USA. Below are the abstracts of posters that were accepted and presented at the conference. The best poster award committee, consisting of J. Davenport, D. Jeffrey, M. Monagan, T. Shaska, T. Sturm, N. Takayama, E. Volcheck and members of the poster committee, assigned the prize to B. Jtittler, J. Schicho, and M. Shalaby for their poster C 1 Implicitization of Planar Curves. All posters are archived and are also available in electronic form from
the ACM SIGSAM web site.
Using computer algebra system SINGULAR:PLURAL for computations in noncommutative polynomial algebras
Authors: Levandovskyy Viktor , Schönemann Hans
Published: January 2007

We give a detailed account of algorithms and applications provided with SINGULAR:PLURAL (we call it PLURAL for short). The poster is done in form of (big) one-page introduction to the capabilities of the system.
A Sister Celine type algorithm for definite summation and integration
Authors: Zimmermann Burkhard
Published: January 2007

Sister Celine's method [2] computes a recurrence for a sum or multisum Σ
∞

k
= 0
f
(
n, k
)

where
f
(
n, k
) is a given hypergeometric term. It was generalized to the
q
-hypergeometric case and to integrals [3].
Medical Plan-Analysis by computer
Authors: Miller P. L.
Published: January 2007

The traditional approach to computer-assisted medical decision-making involves designing a computer system which simulates a physician's decision-making process. This paper describes a different approach: Medical Plan-Analysis (MPA). Instead of trying to tell a physician how best to manage a patient, an MPA system critiques a physician's management plan. It is anticipated that this approach may have a number of potential social, medical, and medicolegal advantages. The MPA approach has been implemented in ATTENDING, a system designed using Artificial Intelligence techniques to critique a physician's plan for anesthetic management.
A macro preprocessor for the simulation language network II.5
Authors: Thuente David J. , Sedlmeyer Robert L.
Published: January 2007

Network II.5 [Garrison 1989] is a powerful simulation tool for the design and analysis of multiprocessor systems, but lacks features to support modelling-in-the-large. We have developed a macro preprocessor, NETPRE, to aid in the construction and maintenance of large simulation models. NETPRE supports symbolic constants, include files, and macros. We show how these features can reduce model development time, increase the readability of model descriptions, and facilitate experimentation.
Optimization of a digital neuron design
Authors: Kampf F. , Koch P. , Roy K. , Sullivan M. , Delalic Z. , DasGupta S.
Published: January 2007

Artificial neural network models, composed of many non-linear processing elements operating in parallel, have been extensively simulated in software. The real estate required for neurons and their interconnections has been the major hindrance for hardware implementation. Therefore, a reduction in neuron size is highly advantageous. A digital neuron design consisting of an arithmetic logic unit (ALU) has been implemented to conform to the hard-limiting threshold function. Studies on reducing the ALU size, utilizing Monte-Carlo simulations, indicate that its effect on network reliability and efficiency is not detrimental. Neurons with reduced ALU size operate with the same computational abilities as full sized neurons.