bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of data type information in an interactive database environment
Authors: Buneman Peter , Winston Ira
Published: January 2007

Despite the enormous advances that have been made in the specification of data types and data models in the fields of programming languages, databases and artificial intelligence; there remain a number of problems in attempting to unify the various approaches to the formal description of data. The purpose of this brief paper is to examine these problems from the point (or points) of view of those people—designers, administrators, applications programmers, and end-users—whose main interest is with databases. In particular, we hope to display special concern for the tools provided for the end-user, who should be the final beneficiary of whatever advances are made.

In order to pin down some of these problems, it is worthwhile to attempt a definition of certain terms used in databases:

1. A
data model
(or
database management system
if one is describing an implementation) is a set of parameterized or “generic” data types.

2. A
database schema
is a set of data types that result from instantiating the generic types of the data model to produce a set of data types that describe the data to be stored.

3. A
database
is an instantiation of those types defined by a schema.
Default reasoning and inheritance mechanisms on type hierarchies
Authors: Carbonell Jaime G.
Published: January 2007

Type hierarchies abound in Artificial Intelligence, Data Bases and Programming Languages. Although their size, use and complexity differs, all share a central inference mechanism:
Inheritance of information
, their
raison d'etre
. This paper discusses various types of type hierarchies and inheritance mechanisms, concluding with a proposed
generalized inheritance mapping
approach to resolve issues of lateral and upward inheritance (to augment the traditional downward approach), as well as default reasoning and limited non-monotonic inference.
Integrating a database system and programming / information environment
Authors: Cattell R. G.G.
Published: January 2007

Vast differences in terminology aside, there is considerable overlap between work in knowledge representation, programming language data types, and database models. Our current work on the Cedar programming environment has necessitated integrating a number of ideas in these areas.

As part of the Cedar project in the Computer Science Lab at Xerox PARC, we have been constructing a database management system. The goal of the Cedar environment is to greatly increase our productivity by combining the best currently known principles from programming languages, programming tools, and user interfaces into a single integrated system. Cedar is based on the Mesa programming language [1]. The goal of our database subproject of Cedar is to provide a uniform prepackaged way to perform access to data structures, as contrasted to the current state of affairs in which Mesa programmers repeatedly re-invent the facilities we intend to provide to type, structure, index, link, robustly store, concurrently access, and cache data stored in the primary or secondary memory of one or more computers on a network.
On the specification of behavioural constraints
Authors: Cristian Flaviu
Published: January 2007

When designing information processing systems, the key problem is to find what symbols and constructs (available in some given language) should be used so as to be able to answer the questions that the users want to ask and to perform the state transitions that the users have to perform in order to keep in step with some reality that is being modelled. If the language that is being used cannot be interpreted directly by the software of a computer (e.g. set theory, algebra, semantic networks), the resulting model is called an abstract model (e.g. a specification, a data base schema). If all of the symbols and constructs used to express the model can be interpreted by a computer, the model is a concrete implementation (e.g. a data base system). Both the abstract and concrete models capture some aspects of the reality that is modelled. They differ with respect to the languages in which they are expressed.

The choice of the languages which are appropriate for writing such models is a subject of intensive debate. The recent workshop on Data Abstraction, Data Bases and Conceptual Modelling has shown that this debate is not likely to diminish in the near future. In the context of this debate, however, a common opinion was expressed several times by data base participants: the data models used to specify data base schemas are lacking to support the specification of operations tailored to particular application environments. It is therefore expected that in the context of data base modelling, the integration of operations (behaviour) with data (structure) will be one of the most fertile research areas for the next few years.
Constraints
Authors: Deutsch L. Peter
Published: January 2007

Most programming systems reflect a model of computation which sharply distinguishes between “passive” data objects and “active” program objects (procedures). Furthermore, procedures describe not only a set of computations but the precise flow of control between them. In contrast, a group at MIT is investigating a new paradigm called
constraints
in which a single kind of object models both data and procedures, and in which the description of procedures minimizes commitment to the order in which computational steps will be executed.

A (primitive) constraint is an object with some
parts
, which correspond to fields of a data structure or input/output parameters of a procedure, and a
body
which describes how to compute the values of some parts from other parts. The body consists of
rules
written in an implementation language (Lisp in the MIT systems). Constraints with no body behave like ordinary data structures; constraints with substantial bodies behave more like procedures. However, unlike procedures, which always compute the same set of outputs from the same set of inputs, a constraint may compute in different directions depending on the available data.
Processing data model abstractions
Authors: Hardgrave W. Terry , Deutsch Donald R.
Published: January 2007

A number of data abstraction, database, and conceptual modeling issues border on the three technical areas that this workshop addresses: artificial intelligence, database management, and programming languages. We assume that the workshop is dedicated to removing the boundaries between these three fields in order to shape research and development of common interest. While enthusiastically supporting this objective, we believe that each area has a unique perspective and emphasis worth preserving. The three fields can truly benefit from each other only if each one appreciates the diversity of these research viewpoints. In this spirit we describe a research project on Abstract Data Models conducted by the Institute for Computer Sciences and Technology (ICST) of the National Bureau of Standards (NBS). Before doing so, however, we wish to discuss from our perspective both some problems that database management shares with the areas of artificial intelligence and programming languages, and some possible mathematical solutions to these problems.
Data dictionaries in open system communication
Authors: Hitchcock Peter
Published: January 2007

My current work is based on the premise that one should be able to access a foreign database system with the same ease that one can move from one type of telephone system to another. Data dictionaries must form the focal point in any architecture which would support such a concept. Data from a foreign system must be presented to the local system in such a way that the local system can understand it if the databases are disjoint, or merge the foreign conceptual model with the local one if the data bases have some common structure. Once such a rapport has been established, other aspects of the conceptual models, such as constraints and operations on the data, must be translated from one system to the other. This raises the following issues which I would like to see discussed at the workshop.
Associating types with domains of relational data bases
Authors: Lacroix Michel , Pirotte Alain
Published: January 2007

In the DB field, there are two
interpretations
(or perceptions or schools of thought)
concerning the relational model
:

(a) one interpretation considers that the relational model contribution to the DB field essentially consists in the presentation of a clear and simple notion of (flat) file, and that many users will be very satisfied to describe their data structures as tables;

(b) another interpretation considers the relational model as a (reasonable) support for a (weak) entity relationship model.
Axiomatic information modeling
Authors: Lundberg Bengt , Bubenko Janis A
Published: January 2007

The obvious task in information modeling is to arrive at a model which is correct. However, the concept of correctness has many faces e g the model must correctly reflect the properties of the application at hand, and it must adequately select relevant parts of the application. The former case requires that the information model is “satisfied by the application”. The latter case is dependent on the intended use of the model. The problem of satisfyability is, in most information modeling approaches, considered to be an intuitive task. From logic we know that a theory, here seen as an information model, can only be satisfied if it is consistent. Thus, by applying predicate logic to information modeling, we should have a possibility of checking the satisfyability of an information model. However, in order to ensure that the information model is satisfied by the application in mind, requires an intuitive reasoning.

Consequently, our plans include to further elaborate the use of predicate logic in information modeling. It furthermore includes a study of possibilities and limitations of such an approach. The results obtained so far will be shortly reviewed in the following.
Use of database organization in the Consul system
Authors: Mark William
Published: January 2007

A fundamental aspect of the Consul system is the way the organization of the database defines the system's operation and unifies its components. Accessing and maintaining the database is the focus of all system activities, from parsing English to executing programs.
Make more of data types
Authors: Mayr Heinrich C.
Published: January 2007

This position paper refers to some observations I made at the 'High Level Abstraction Workshop', and it exhibits a way to attack abstraction and specification problems in the database field. Because of the fixed page limit this will be done in a more or less cursory collection of remarks.
On conceptual database modelling
Authors: McLeod Dennis
Published: January 2007

This research was supported, in part, by the Joint Services Electronics Program through the Air Force Office of Scientific research under contract F44620-76-C-0061.
Multiple points of view in modelling programs
Authors: Rich Charles
Published: January 2007

An important issue discussed at the workshop on data abstraction is the need to represent multiple, overlapping points of view and relationships between them. The first two sections of this paper motivate the use of multiple and overlapping points of view in modelling programs and data structures. The final section of the paper briefly describes a new formalism, called

overlays

, which has been developed for this purpose, and which may be of general interest.

The overall goal of the research from which this paper is drawn is to compile a

library

of standard, generally used data and control abstractions to be used in the interactive analysis, synthesis and verification of programs. Multiple points of view were needed in this context is in order to decompose the data and control structures of users' programs in a way which makes explicit their relationship to the library of standard abstractions.
Issues in the design of database programming languages
Authors: Rowe Lawrence A.
Published: January 2007

This paper discusses two issues in the design of database constructs for programming languages. The first issue is whether records in a database correspond to records in a programming language or to a distinct type such as
tuple
. The second issue is what facilities are provided to define the interface between an application program and a database.

The discussion below is based on our research on the RIGEL database programming language [Rowe 79, 80a]. RIGEL is a block-structured language with constructs for accessing relational databases, a
module
construct for data abstraction, and an exception-handling mechanism. The first implementation of the language has recently been completed and is being distributed.
Towards constructive axiomatic specifications
Authors: dos Santos C. S. , Furtado A. L. , de Castilho J. M.V. , de Carvalho S. E.R.
Published: January 2007

The main goal of our efforts is the specification of data bases whose structure and behaviour are restricted by semantic integrity constraints. Research proceeds along the following stages:

1. Choose a data model;

2. Establish a taxonomy of integrity constraints;

3. Specify the data model formally;

4. Develop a methodology for specifying conceptual schemas for different applications, based on the data model;

5. Provide a conceptual characterization of query and update operations.
Database management systems past and present
Authors: Sibley E. H.
Published: January 2007

The theme of this note is on the two points:

1. Many of the ideas discussed in both data base and the other two areas were well known in the sixties—some go back to the fifties.

2.Too much attention was placed on trivia.
A conceptual schema for Knowledge-based systems
Authors: Sowa John F.
Published: January 2007

Knowledge-based systems are data bases with more powerful front ends for dealing with the meaning of data. This paper discusses requirements for a conceptual schema that is general enough to support knowledge bases as well as ordinary data bases. It presents seven features that such a schema must support and evaluates various approaches to data base semantics in terms of them. The AI notations for semantic networks or conceptual graphs are highly general ones that can support all seven features.
Data abstraction, data bases and conceptual modelling (Position Paper)
Authors: Thatcher J. W.
Published: January 2007

There is no paper with a mathematical foundation that I know of that strikes more at the heart of the subject of this Workshop than that of R.M. Burstall and J.A. Goguen [10], presented at the Fifth International Joint Conference on Artificial Intelligence in August of 1977.
The extension of data abstraction to database management
Authors: Wasserman Anthony I.
Published: January 2007

The long-term goal of the User Software Engineering (USE) project at the University of California, San Francisco, is to provide an integrated homogeneous programming environment for the design and development of interactive information systems. Realization of this goal involves the development of new software tools, their integration with existing tools, and the creation of an information system development methodology in which these tools are systematically used [1,2].

The successful construction of interactive information systems requires the utilization of principles of user-centered design [3,4,5], combined with features traditionally associated with the separate areas of programming languages, operating systems, and data base management [6]. It has become increasingly clear that the key to being able to provide such a unified view lies in providing a unified view of data [7]. The potential benefits of such a unification are considerable, including:

1) conceptual simplification of the system structure permitting, for example, joint design of data structures and data bases

2) the elimination of duplication or inconsistencies among diverse software components

3) the ability to achieve greater reliability in systems because of reduced dependence upon multiple software systems
Constructive Abstract Data types (CAD)
Authors: Wedekind Hartmut H.
Published: January 2007

1. Distinction from conventional approaches

The motivation for CAD is to extend the idea of data abstraction to application programming. Conventional approaches confine themselves to operational concepts of system programming like STACK, QUEUE etc. and do not consider concepts like CONTRACT, INVOICE etc. of the application world (AW) with an arbitrary number of operations applicable to them, including those of the ad hoc type.
Types, algebras and modeling
Authors: Zilles Stephen N.
Published: January 2007

Programming languages, database systems and artificial intelligence systems all have the notion that entities can be classified into
types
. As might be expected, however, the usage of the notion of type is not the same throughout or even within these areas. In this paper, I propose a notion of typing that is derived from work on programming languages and indicate how this notion might be used in the context of database systems. Thus, the paper is a step toward unifying the notions of type in data-bases and programming languages.
Community portals through communitization
Authors: Donnelly Vanessa , Merrick Roland
Published: January 2007

Governments wishing to achieve high citizen adoption from electronic services need to provide solutions that are not only technically accessible, but usable and engaging to large numbers of people. Citizen diversity makes this a real challenge. Designing the best user experience for diverse users will require alternative designs on potentially different devices. The cost of doing this may prove prohibitive. One answer is to leverage "the third sector" i.e. voluntary organizations, special interest groups, communities and business related support organizations. Third sector organizations traditionally provide support to disadvantaged and potentially excluded groups and provide a way for government to increase social inclusion and reach a wider audience.To support the delivery of government information and services through multiple providers including but not restricted to the originating government version, this paper proposes to introduce the concept of
"Communitization"
. The principle behind
"Communitization"
is to enable an interface to be adapted to suit the wants and needs of a community. For government this would provide a way to reach a broader set of citizens with a more tailored set of solutions without incurring any incremental cost. The benefit to citizens would be a custom design, tailored to their needs and integrated into sites they already use.
How universal is good design for older users?
Authors: Hawthorn Dan
Published: January 2007

This paper attempts to illustrate the way in which multiple considerations influence interface design decisions when designing for older users. The arguments are supported by examination of issues that arose during the design of a successful email system for older users. The point is also made that while the interface design decisions made in the example do assist older users, they limit the power of an application to serve younger, more able and more demanding users. The argument is made that while it is possible to increase accessibility, the most obvious ways of doing this limit the universality of the resulting application.
Patterns for encapsulating speech interface design solutions for older adults
Authors: Zajicek Mary
Published: January 2007

An increasing number of older adults will need to use computers and computer related systems in the future to avoid social exclusion and enable them to live more independently in the future. There are therefore currently many interface designers searching for pointers to good design for older adults, a user group which is significantly different from the mainstream younger user groups mainly as a result of age associated impairments. There is currently no detailed body of knowledge from which interface designers can learn how to cater for this user group. This paper suggests a framework for encapsulating good interface design for older adults which is based on rigorous experimental work and sets out the findings in the form of patterns, a representation which has already been used successfully in the domain of software engineering and architecture.A robust framework for interface design is particularly important as those designing systems for older adults tend to be younger people who have no concept of what it is like interact with computerized systems as an older person with the age associated impairments.
Countering design exclusion through inclusive design
Authors: Keates Simeon , Clarkson P. John
Published: January 2007

The world population is aging and the number of people who are experiencing a loss of functional capability is also on the increase. There is a need to design 'inclusive' products to accommodate this wider range of capabilities and to develop metrics to assess the success of such products. Successful inclusive design requires a balance between the demands a product makes of its users and the users' capabilities, along with a number of design metrics and data to enable their evaluation. If the balance is not correct, then there is the potential for design exclusion.
Theoretical and architectural support for input device adaptation
Authors: Wang Jingtao , Mankoff Jennifer
Published: January 2007

The graphical user interface (GUI) is today's
de facto
standard for desktop computing. GUIs are designed and optimized for use with a mouse and keyboard. However, modern trends make this reliance on a mouse and keyboard problematic for two reasons. First, people with disabilities may have trouble operating those devices. Second, with the popularization of wireless communication and mobile devices such as personal data assistants, the mouse and keyboard are often replaced by other input devices. Our solution is a tool that can be used to translate a user's input to a form recognizable by any Windows-based application. We argue that a formal model of input is necessary to support arbitrary translations of this sort. We present a model, based on Markov information sources, that extends past work in its ability to handle software-based input such as speech recognition, and to measure relative device bandwidth. We also present our translation tool, which is based on our model, along with four applications built using that tool.
Making chalk and talk accessible
Authors: Bennett S. , Hewitt J. , Kraithman D. , Britton C.
Published: January 2007

This paper investigates the development of an authoring package designed to mimic traditional "chalk and talk" delivery of content in education. It emphasizes the twin goals of making the output more accessible both for those with disabilities and for distance learners and also making the package usable by academic staff without requiring extensive training. It deals with issues arising from the capture of the material, the compromises and conflicts which are made in the satisfaction of accessibility guidelines and the implementation problems which arise. An authoring tool designed specifically for the production of accessible multimedia material is described as is preliminary work being undertaken to provide live subtitles of lectures.
Towards the creation of accessibility agents for non-visual navigation of the web
Authors: Kottapally K. , Ngo C. , Reddy R. , Pontelli E. , Son T. C. , Gillan D.
Published: January 2007

In this paper, we highlight the main research directions currently pursued by the investigators for the development of new tools to improve Web accessibility for users with visual disabilities. The overall principle is to create intelligent software agents used to assist visually impaired individuals in accessing complex on-line data organizations (e.g., tables, frame structures) in a meaningful way. Accessibility agents make use of knowledge representation structures (automatically or manually derived) to assist users in developing navigation plans; these are employed to locate given pieces of information or to answer user's desired goals.
Designing a universal keyboard using chording gloves
Authors: Lee Seongil , Hong Sang Hyuk , Jeon Jae Wook
Published: January 2007

A universal input device for both text and Braille input was developed in a Glove-typed interface using all the joints of the four fingers and thumbs of both hands. The glove-typed device works as of now for input of Korean characters, numbers, and Braille characters using mode conversion. Considering the finger force and the fatigue from repeated finger motions, the input switch was made of conductible silicon ink, which is easy to apply to any type of surface, light, and enduring. The usability testing with (1) blind subjects showed the performance matching with a commercial Braille keypad, and (2) non-blind subjects for Korean characters showed comparable performance with cellular phone input keypads, but inferior to conventional keyboard. Subjects' performance showed that the chording gloves can input approximately 122 Braille characters per minute and 108 words per minute in Korean character. The chording gloves developed in our study is expected to be used with common computing devices such as PCs and PDAs, and can contribute to replacing the Braille-based note-takers with less expensive computing devices for blind users.
Designing cognitive technologies for people with disabilities - perspectives for theory and practice
Authors: Sullivan Jim , McGrenere Joanna
Published: January 2007

This panel will identify and discuss practical and theoretical issues in the design, implementation, and evaluation of technologies to assist persons with developmental and acquired cognitive deficits.
A study in reading comprehension improvement
Authors: Waivio Rodica
Published: January 2007

As everyday computing plays an increasingly prominent role in our daily lives, user reading comprehension is of vital importance for human progress. This paper proposes to investigate the improvement of the user reading comprehension by different factors. Two main experiments tested how an explicit display of a small collection of keywords and a summary explanation aid reading comprehension. Twelve subjects were used for the first experiment and eight subjects for the second experiment. All were UIC undergraduate and graduate students, with computer experience. In the post experimentation stage, the subjects recommended different techniques for reading improvement. Comprehension was estimated by two procedures, a quantitative evaluation by a comprehension questionnaire and a qualitative evaluation by the subjective report. Important results were pointed out by the subjective evaluation. The advantages and disadvantages were summarized by a small focus group of users. A Dynamic Reading Device was designed for experimentation usage.
Designing an interface usable by people with dementia
Authors: Alm Norman , Dye Richard , Gowans Gary , Campbell Jim , Astell Arlene , Ellis Maggie
Published: January 2007

Caring for people with dementia will be one of the major challenges of the 21st century. Advancing technology may offer ways to augment and supplement human care, if it is sensitively designed with the needs of potential users always taken into account. Developing an interface that a person with dementia can make sense of and use is a difficult goal. Beginning to meet this challenge is one aspect of a programme we have embarked on to develop a multi-media system that can be used to help people with dementia communicate better with others. Reminiscence work with people with dementia is a valuable tool for enabling them to participate meaningfully in conversations. We are developing a system which uses multimedia technology as an effective vehicle for delivering reminiscence stimulus and thus conversation support for people with dementia.
Utilizing resource-rich nodes in Ad hoc networks
Authors: Chakeres Ian D. , Belding-Royer Elizabeth M.
Published: January 2007

In wireless ad hoc networks heterogeneity is inherent; each node has different characteristics, resources and purpose. Current ad hoc routing protocols do not take node heterogeneity into account when making routing decisions; they consider each node indentical in capabilities. We propose a simple way to modify the route discovery phase of an on-demand routing protocol to choose the "best" route, considering heterogeneity. The Ad hoc On-Demand Distance Vector Routing protocol (AODV) [1] is modified and the performance validated in experimental tests. It is shown that by considering heterogeneity during route discovery, paths that contain more capable nodes are utilized, thereby avoiding resource-poor nodes.
A robust header compression technique for wireless Ad hoc networks
Authors: Sridharan Ranjani , Sridhar Ramalingam , Mishra Sumita
Published: January 2007

Due to the limited bandwidth of the wireless links in ad hoc networks, compressing the packet headers is an attractive method for efficient usage of the frequency spectrum and for performance enhancement. The objective of this work is to demonstrate the use of a novel end-to-end header compression technique for multi-hop wireless ad hoc networks. Our preliminary analysis shows a significant performance improvement when the proposed Routing-Assisted Header Compression (RAHC) technique is implemented in conjunction with conventional on-demand routing techniques for ad hoc networks.
Memory leaks in derived types revisited
Authors: Stewart G. W.
Published: January 2007

In a note in the
Fortran Forum
, Markus describes a technique for avoiding memory leaks with derived types. In this note, we show by a simple example that this technique does not work when the object in question is a parameter in nested subprogram invocations. A fix is proposed and illustrated with code from MATRAN, a Fortran 95 package for performing matrix manipulations.
Some reflections on the current state of automatic Braille translation
Authors: Coleman Philip W. F.
Published: January 2007

This paper outlines current work in Britain on Braille translation by computer. It goes on to explore possible programming methods, highlighting problems and suggesting solutions. It finishes by examining the feasibility of an international index of Braille software, suggesting a possible implementation.Before I begin, may I say first, how pleased and privileged I feel to be here today - my pleasure will be all th e greater if this conference achieves something really positive; and second, how grateful I am to Professor Werner for inviting me - I hope he will feel that my presence is worthwhile.So much has been written already about Braille translation by computer that I feel doubtful about how much that is original there is for me to add. However, in this paper, I shall begin by outlining the work proceeding in the United Kingdom; I shall go on to suggest some programming techniques worth investigating when implementing Braille translation systems; and finally I shall talk about the possibility of the international pooling of Braille translation programs and of information about them.
Implementation of character string pattern matching on a multiprocessor
Authors: Vineberg Maniel
Published: January 2007

An algorithm to do pattern matching, a basic character string operation, is presented. The Programmable Algorithm Machine (PAM), a proposed special-purpose computer which will feature multiple processing elements and operate efficiently over a wide class of applications, is described. It is shown that the multiple processing elements of the PAM allow concurrent execution of independent operations both in a special case of the pattern matching algorithm, where the string sizes (lengths) are known at compile time, and in the general case, where the sizes are not known.
Associative/parallel processors for searching very large textual data bases
Authors: Bird R. M. , Tu J. C. , Worthy R. M.
Published: January 2007

This paper describes an approach to solving a major problem in the information processing sciences— that of searching very large (5-50 billion characters) data bases of unstructured free-text for random queries within a reasonable time and at an affordable price.

The need by information specialists and knowledge workers for large, fast low-cost text and document retrieval systems is growing rapidly. Conventional approaches to the problem have usually depended upon expensive, general purpose computers, upon special pre-preprocessing of the textual data (e.g. file inverting, indexing, abstracting, etc.), and upon elaborate, costly software. The resulting retrieval systems often cost hundreds of dollars per query and the full scanning of an uninverted, unstructured billion byte textual data base could take hours of computer services. However, in spite of these restrictions, such full text search systems have proved useful and even indispensible for many applications.

Computer technology of the late 1960's and the 1970's, in both hardware and software (e.g., minicomputers, low-cost, high density disk storage, “chip” electronics, natural language query systems, etc.), have made i t practical to build special purpose, low-cost text retrieval systems. Such a system has been built, tested, and is now in a production stage. The system called the Associative File Processor (AFP), utilizes a conventional minicomputer (DEC's PDP-11/45) for control, off-the-shelf high density disks for storage, a special purpose parallel search module as a text term detector, and query and retrieval software. The AFP is currently being field tested at two sites. Full text, parallel searches on un-preprocessed textual data bases are being performed at the effective matching rates of 4 billion bytes per second (8K byte key memory times 500 Kbyte/second data stream). Estimated costs are 10 to 25 cents per query for a one billion byte data base. The costs per query and the time for searching increase in a linear fashion as data base increases. A basic architecture for the AFP is described and an implemented version is discussed. A more powerful term detector module is also under development. This system is designed around a finite state automaton algorithm.
The architecture of a database computer - a summary
Authors: Hsiao David K. , Kannan Krishnamurthi
Published: January 2007

The motivation for seeking hardware solutions to database management functions traditionally carried out by software has been apparent to data-base designers for sometime now. Firstly, database management software has grown in complexity and size over the years. This growth is prompted by the increase in user requirements, by the formulation of sophisticated models and by the change in data processing mode from an off-line, batched, single user environment to an on-line, concurrent and multi-user environment. Large and complex software systems tend to be failure-prone. Further-more, practical verification methods for software systems are still not in sight. On the other hand, methods for verifying hardware functionality, design and production have long been available. Advanced technology has also overcome some of the problems of the logic complexity and capacity requirements, making the construction of relatively large and complex computers viable. By incorporating basic database management functions into hardware, not only can we provide more reliable basic functions, but we can also improve the software reliability since the software requirements will be less complex and the system software will be smaller in size.
The data management machine, a classification
Authors: Rosenthal Robert S.
Published: January 2007

There has been much interest in the use of special purpose processors as the data base management component of data processing systems. The generic terms “backend” and “data management machine” have been applied to such devices. Examination of the literature reveals a broad cross section of host to backend functional distribution and interconnection methodology. This discussion represents an attempt to examine and classify several of these backend data base management machine configurations in terms of their operational parameters and application constraints. A formal taxonomy of such systems remains yet to be performed.

At least three distinct classes of data management machine (DMM) are evidenced in the literature; they are the large host backend, distributed network data node and smart peripheral. The intended classes of problem that the various authors envision amenable to solution by the DMM approach exhibit overlap while the performance envelope in which each DMM architecture would provide a technically acceptable, economically sound solution to a given user requirement set varies. Some of the papers used as source for this work contained no explicit mention of either the problem classes or performance constraints that the described configuration was to address; thus liberty has been taken in interpreting the implicit application goals of these authors.
Trends in non-software support for input-output functions
Authors: McDonell Ken J.
Published: January 2007

Input-output subsystem architectures have evolved over the past 20-odd years to the point where two divergent approaches have found acceptance in current computer systems; the 'IBM channel' is the archetype of the lower level alternative, while the functionally more complex techniques involve a wide spectrum of distributed processor architectures supporting database and/or storage management functions independently with respect to the central processor. The paper traces the historical development of support (outside central processor based software) for input-output functions and concludes with a preliminary comparison of the relative merits of the software interfaces provided by the alternative input-output subsystem architectures.
A comparison of sequential and associate computing of priority queues
Authors: Landson Barry M. , Sargent Robert G.
Published: January 2007

A comparison of priority queues on four different types of computer memories are made by ring a model to determine the total time to do comparable tasks. The four types of memories compared are random access (RAM), associate (AM), hybrid consisting of an associate memory and a random access memory (AM/RAM), and the hybrid memory with an auxiliary memory having the @@@@pability to perform Lewin's Associate algorithm @@@@], (AM/RAM/AML).

The model used for the comparisons is an extension of the MIX model developed by Knuth [1]. The MIX model was extended to include the four types of memories and the instruction set expanded include @@@@ instructions for the memories added. This @@del allows direct comparisons to be made of the different architectures and different software algorithms in performing the same tasks.
A compact normal walk model for PCS networks
Authors: Tuan Chiu-Ching , Yang Chen-Chau
Published: January 2007

Model-based movement patterns play a crucial role in evaluating the performance of mobility-dependent Personal Communication Service (PCS) strategies. This study proposes a new normal walk model to represent more closely the daily movement patterns of a mobile station (MS) in PCS networks than a conventional random walk model. The proposed walk model uses a drift angle θ to determine the direction in which an MS leaves a hexagonal cell in the next one step. The angle θ is assumed to approach the normal distribution with the parameters: μ = 0° and σ is on the interval [5°; 90°], based on the concept that most trips follow the shortest path, to make the movement patterns more realistic. A compact classification that types cells with side indices is further developed to partition an n-layer cluster of PCS networks into 12 mirror regions; consequently, the number of states can be reduced significantly, and the computational complexity is also reduced in the probability derivation. Two metrics are formulated in experiments to measure the expected and average numbers of steps taken by an MS to move out of an n-layer cluster. Experimental results confirm that for σ = 10°, 30°, 60°, and 90°, the discrepancies between the analytical computations and the simulated values are all within ±0.46%, and most are even within ±0.35%. Moreover, when σ is set to 71°, a normal walk can almost represent, and even replace, a conventional random walk, since the discrepancies between them are all within ±0.71%.
An array based simulation approach for predicting the impact of different measles vaccination strategies in Lower Saxony
Authors: Dreesman Johannes M.
Published: January 2007

Based on measles case data from pediatricians in Lower Saxony, a simulation study was conducted in order to reproduce the current vaccination-disease relationship and afrerwards predict the impact of different vaccination strategies. The programs were written in S-Plus and make use of the language's array processing facilities. The process of infection was modeled by means of an age-structured compartmental model. The main data structure is a two dimensional array, representing the complete population, partitioned according to age cohorts and the compartments, which represent the stages of infection. The flow of individuals through the compartments is modeled weekly and performed by means of array operations. The number of new infections in each age cohort is simulated as a Poisson random variable, depending on the number of infectious individuals of any age and the transmission probability between ages. The transmission coefficients are organized in a matrix enabling the transmission process to be computed by matrix multiplication.
The A+ programming language, a different APL
Authors: Girardot Jean-Jacques
Published: January 2007

This paper introduces A+, which is an Array Oriented programming language derived from APL, and explains the motivations for creating such a language.

After discussing of some problems of current APL system, like the lack of control structures, the usage of dynamic binding, and the difficulty of handling functions, we present how these problems are solved in A+.

The most important feature of A+ is that it uses lexical binding rather than dynamic binding as APL does, which solves some old problems of APL while making it a safer language, and offers a new kind of programming style.
Neural networks in APL
Authors: Alfonseca Manuel
Published: January 2007

Neural networks are fairly straightforward to program in a matrix oriented language such as APL. The only general improvement that would benefit them would be the implementation of sparse matrics. Small networks can be trained quite easily using the standard procedures (back propagation, etc).
Conscientious programming using PMA
Authors: Barker Guy , Keenan Douglas J. , van Loon Herman
Published: January 2007

This paper describes the use of APL systems at Philips to assist in providing a controlled application support environment and examines in detail an APL software management system, PMA (Program Maintenance Aid).
ACORN
: APL to C on real numbers
Authors: Bernecky Robert , Brenner Charles , Jaffe Stephen B. , Moeckel George P.
Published: January 2007

a prototype APL to C compiler (
ACORN
: APL to C On Real Numbers) was produced while investigating improved tools for solving numerically intensive problems on supercomputers.
ACORN
currently produces code which runs slower than hand-coded Cray FORTRAN, but we have identified the major performance bottlenecks, and believe we know how to remove them. Although created in a short time on a limited budget, and intended only as a proof of the feasibility of compiling APL for numerically intensive environments,
ACORN
has shown that straightforward compiled APL will be able to compete with hand-optimized FORTRAN in many common supercomputer applications.
Preliminary mesh checking for structural analysis
Authors: Capra Renato
Published: January 2007

The purpose of this work is to provide tools for checking the nodes and elements of a Finite Element Model for Structural Analysis.

All the checks related to single elements (warping and stretch factor, interior angles) can be performed on the whole model with APL scalar functions (without any loop).

Operations that involve comparison between elements (such as checking for coincident nodes and coincident elements) require a non-trivial approach. A simple algorithm for recursive space-splitting is described, along with performance considerations for large models.

Graphic output obtained using the Graphics Support Library of RTPC and an interface to Interleaf Workstation Publishing System are also provided.
APL trivia
Authors: Cherlin Edward
Published: January 2007

APL derives great expressive power from seemingly trivial features, such as empty arrays, but there is still resistance to the implementation of the elementary trivial functions including left/stop ⊣ and right/pass ⊢, which perform no calculations. This paper defines functional triviality; describes trivial functions and operators and their uses; discusses the mathematical basis of their expressive power; and defines new trivial functions and operators. It urges implementation of several of these functions as primitives for reasons of efficiency and expressiveness, and considers their efficient implementation via idiom recognition.
Analytic response time model for distributed systems
Authors: Cook Janice H. , Groner Leo H.
Published: January 2007

Network designers are faced with a combinatorial explosion of choices not only among various vendors' workstations, hosts and servers, but also among application distribution strategies, communication media, communication protocols, and network topologies. To study performance trade-offs among various designs, the authors have developed a generic system thruput and response time model for distributed systems. We have applied the model to actual customer networks.

The modeller describes the system in a language of model statements describing operations, resources, submodels, parameters and transactions flows. Model statements are “compiled” into arrays that form the input to the analytical queueing network model.

The modeling package is written in APL2 and is based on an earlier VSAPL package developed for manufacturing planning. Since the package is designed with an open set of submodel types, and since APL2 is portable across many architectures and operating systems, we can easily integrate non-APL2 code.
Arrays and references
Authors: Girardot Jean-Jacques
Published: January 2007

Generalized arrays in APL have been for long a very controversial subject. Since we are now undertaking the redaction of an extended standard for APL, it seems legitimate to reopen the old debate.

An analysis of both nested and boxed array systems, in the light of a new development in APL which consists of the introduction of a new data-type in the language, shows the interest of having both systems with their own specificities.
Markov processes in APL
Authors: Hawkes Alan G.
Published: January 2007

Using examples from two areas of application, ion channel models and systems reliability, we illustrate the power of APL as an executable notation for the mathematics of finite-state Markov processes. We stress, in particular, the algebra of partitioned matrices and second-generation features of DYALOG APL which allow a simple natural way of creating certain structured matrices.