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Rensselaer has launched a new Bachelor of Science degree program in Information Technology [4,5]. This degree is an alternative to the more traditional computer science or computer systems degrees that Rensselaer continues to offer. It focuses on the application of computing and communications technologies in a student-chosen application area called a second discipline. The expectation is that a company doing business in the second discipline or closely related area will employ a student completing this degree.

We address the authorization of access privileges to users in a local database management system (DBMS) that is interoperating in a distributed database system (DDBMS). Our focus is on the potential in a next generation security system for delegation access concepts such as role hierarchy delegation to violate the security policy in a local database system that is part of the distributed system. This kind of violation can be categorized as a violation of local autonomy. We propose a labeled graph model to detect such a problem.

This paper relates experience in exploiting a science and engineering case study approach to teach introductory computing concepts in a course for non-majors. It describes how a case study is structured and implemented using hypermedia. It also discusses experience gained in using the case studies in the course.

Multidisciplinary concurrent engineering needs to model and manage different views of complex designs. Previous attempts to address the problem of creating views of complex objects in object oriented database systems focus on the structure of complex objects; little attention is paid to how complex object behavior is effected when creating views. We believe that designing functionally correct behavior for a complex object should be a major consideration when defining a view to guarantee correctness of the derived classes.In this paper, we study the problem for designing functionally correct views of complex objects in concurrent engineering. View behavioral modeling requirements are presented. A behavior model that satisfies these requirements is presented. This model is demonstrated on an example complex object that represents process management.

Abstract Numerous engineering application systems have been developed over the past twenty years, and many of these applications will continue to be used for many years to come. Examples of such applications include CAD Systems, finite‐element analysis packages and inspection systems. Because many of these applications were developed before graphical workstations became available, they often have simple command‐line user interfaces. Thus, there is a need for a graphical user interface management system (UIMS) that can be used to build point‐and‐click style interfaces for these existing engineering applications. In this paper we describe such a UIMS, and discuss its implementation using an object‐oriented database tool. This UIMS allows users to create and modify user interfaces by editing graphical representations of the interfaces, thus eliminating the need to write code to build or modify an interface. The UIMS is implemented using an object‐oriented database tool to take advantage of the data manipulation and storage management capabilities it provides. This approach reduces both the quantity and complexity of the code needed to implement the UIMS. It also allowed the UIMS to be implemented in a minimal amount of time.

The relational object system for engineering (ROSE) is an experimental database system for interactive engineering applications. The ROSE system and the way it uses object technology are described. The system has an open architecture which allows new tools to be added easily. Several tools are described, including an inheritance manager, version control system, and user interface manager. These tools enhance the ROSE system and broaden its application to other types of data-management problems.>

Entities such as mechanical assemblies are recursive when they contain other assemblies at a lower level of detail. In this paper we show how recursive CAD entities can be manipulated using an extended projection function. The new function finds nested sub-entities within entities that are modeled as trees of aggregations and generalizations. It allows these sub-entities to be found using expressions that are independent of the complexity of an entity's data structure. We describe the new function, its relationship to the transitive closure function, and its implementation in a CAD database system.

Purpose. This paper defines a layered functional architecture that is useful for describing interfaces (data or parameter exchanges) between Ada and Data Management Systems (DMS). It uses this architecture in discussing potential approaches to implementating standard interfaces between Ada and both relational and CODASYL DMSs.

This paper focuses on the problem of management of CAD data by investigating the use of the software engineering principles of data abstraction and object-oriented programming as means for managing the volume and complexity of design data. It discusses how a data management system which manages abstract data types provides a framework for integrating a CAD environment by providing a single mechanism to manage data, programs, and the manipulation of the data with the programs. It also shows how two forms of abstraction, aggregation and generalization, can be used to model hierarchies of parts and components, and multiple design alternatives, respectively. These abstractions are then used to model the geometrical and topological data required to describe three-dimensional mechanical parts.

One of the major obstacles in CAD is the lack of available software systems that can effectively manage the massive amounts and diverse types of data necessary to describe designs. In this paper, we focus on this problem by investigating the use of data abstraction, a software engineering principle, as a means of managing the volume and complexity of design data.

Software applications involving interactive computer graphics are made up of several components. One of these is a data modeling component. This data modeling component is often application dependent and therefore difficult to integrate with the data model of other related applications. One solution to this problem is to interface a DBMS with an interactive graphics system to reduce data model dependency and increase sharing of data. This also has the advantage of allowing novice users to use computer graphics by eliminating the need for the user to write complex programs invoking the graphics system.This paper explores these ideas by discussing the implementation of a prototype interface between a relational DBMS and an interactive computer graphics system. It presents both the database structures used to manage the data and the techniques used to design the interface. It concludes by discussing an approach for making the interface portable.

Database management systems (DBMS's) today are usually built as subsystems on top of an operating system (OS). This design approach can lead to problems of unreliability and inefficient performance as well as forcing a duplication of functions between the DBMS and OS. A new design approach is proposed which eliminates much of this duplication by integrating the duplicated functions into independent subsystems used by both the DBMS and OS. Specifically, an I/O and file support subsystem and a security subsystem are defined. Both subsystems make use of a logical information model which models the stored information in secondary storage. The new database operating system organization and the logical information model are presented in detail. Design of the security subsystem is based on the access control model, and is extended with Boolean predicates to produce an access control model capable of enforcing content-dependent security policies. The access matrix is implemented using a combination of access lists and capabilities. Authorization models and multiple user processes are discussed in relation to the new system organization. The outline of a formal specification and proof of correctness of the security subsystem is also discussed.

Many roundoff analyses of nomteratlve methods from numerical linear algebra can be performed, at least in part, using off-the-shelf software.Such software is presented here and its use is illustrated with examples.The package presented differs from Its predecessor in four important respects.First, a mmicompfler allows easy specIficatmn of the algorithm being tested.Second, the package can test the simultaneous effect of rounding error upon several values.Third, it deals with branching in numerical methods, e.g. with pivoting in Gaussian elimination.Fourth, m addition to comparing rounding error with perturbations of the problem, it can directly compare rounding errors in two competing algorithms Key Words and Phrases automatic roundoff analysis, numerical stability, numerical hnear algebra CR Categories 5 10, 5 11, 5 14 The Algorithm Software for Roundoff Analysis.

article Artifacts Evaluated & ReusableArtifacts AvailableAlgorithm 532: software for roundoff analysis [Z] Share on Authors: Webb Miller Department of Mathematics, University of California, Santa Barbara, Santa Barbara, CA Department of Mathematics, University of California, Santa Barbara, Santa Barbara, CAView Profile , David Spooner Department of Computer Science, 303 Whitmore Laboratory, Pennsylvania State University, University Park, PA Department of Computer Science, 303 Whitmore Laboratory, Pennsylvania State University, University Park, PAView Profile Authors Info & Claims ACM Transactions on Mathematical SoftwareVolume 4Issue 4December 1978 pp 388–390https://doi.org/10.1145/356502.356497Online:01 December 1978Publication History 5citation222DownloadsMetricsTotal Citations5Total Downloads222Last 12 Months1Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

For numerical programs, or more generally for programs with floating-point data, it may be that large savings of time and storage are made possible by using numerical maximization methods instead of symbolic execution to generate test data. Two examples, a matrix factorization subroutine and a sorting method, illustrate the types of data generation problems that can be successfully treated with such maximization techniques.