摘要:

AbstractThe Cook and Kim algorithm is a well known method for sorting presorted lists. This paper presents observations based on an implementation of the algorithm on a single processor. An extension of the algorithm to a tightly coupled multiprocessor will also be presented. The performance of the parallel version of the algorithm on presorted lists will be compared to that of a heavily used parallel sort algorithm for tightly coupled multiprocessors, Parallel Quicksort.

ISSN:0038-0644    

DOI:10.1002/spe.4380191002

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractA number of software management tasks (consistent system construction, system installation, etc.) can be performed by automatic tools. Given a particular software system, such a tool requires atask modelthat describes how the task is to be applied to the system. For example, a system construction tool needs to know which operations (compilation, linking, etc.) must be applied to which modules.Unfortunately, although task models are convenient for an automatic software management tool, they are inconvenient for users for two reasons. First, users have to create and maintain multiple, partially redundant models. Secondly, task models are often quite awkward to deal with‐a primary source of difficulty being the need to specify low‐level, task‐specific details.In recognition of these problems, recent software management tools have been moving away from task models towards structural models (e.g. who calls who) as a user interface. Structural models are easy to deal with, because they contain high‐level, task‐independent relationships, rather than task‐dependent details.A prototype tool has been implemented that makes this change complete. The tool automatically performs a variety of software management tasks using a single structural model for a system. The tasks themselves are described separately using system‐independent task

ISSN:0038-0644    

DOI:10.1002/spe.4380191003

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractA comparison was made between using a simulation language to run models on a mainframe computer and on a microcomputer with a hard disk. The study was performed at NASA Langley using both the SLAM II mainframe and PC versions. The procedure for executing SLAM II on a PC is given. A batch job was created to simplify this procedure and allows PCs with a hard disk to execute simulations with one command. NASA's space transportation system operations model and the examples in the SLAM II text were used as a basis for the comparison. The PC simulations completed in predictable times. These were almost always faster than the more unpredictable mainframe times.

ISSN:0038-0644    

DOI:10.1002/spe.4380191004

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThis article presents a procedure for constructing a near‐perfect hashing function. The procedure, which is a modification of Cichelli's algorithm, builds the near‐perfect hashing function sufficiently fast to allow larger word sets to be used than were previously possible. The improved procedure is the result of examining the original algorithm for the causes of its sluggish performance and then modifying them. In doing so an attempt was made to preserve the basic simplicity of th original algorithm. The improved performance comes at the expense of more storage. The six modifications used to improve performance are explained in detail and experimental results are given for word sets of varying si

ISSN:0038-0644    

DOI:10.1002/spe.4380191005

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractTGMS (tiered geometric modelling system) is an experimental system intended to reduce the difficulty and cost of developing new solid modelling applications while preserving investment in an existing, time‐tested, solid modeller. The application developer writes programs in the TGMS language, which consists of a base language augmented by data types (classes) for geometry. The base programming language is AML/X, an object‐oriented language intended for use in design and manufacturing applications. Solid modelling is done using an interface to GDP (geometric design processor), an existing, production‐quality solid modelling system. TGMS shows how a system written in a non‐object‐oriented language can be used as a base for an object‐oriented application programming environment.This paper presents the design of TGMS and discusses important aspects of its implementation. The TGMS language defines classes and methods that provide an interface to functions and data represented in a non‐object‐oriented language. To implement TGMS, issues related to communication, storage management and consistency were addressed. These, and other, implementation issues are discussed. The paper includes sample programs and a summary of feedback from TGMS users. It concludes that the use of object‐oriented programming for geometry has many benefits, and that an object‐oriented system can be built on top of a non‐object‐oriented system at less cost than building the equivalent object‐ori

ISSN:0038-0644    

DOI:10.1002/spe.4380191006

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380191001

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY