Program dependency graphs (PDG) facilitate program analysis and related applications such as program slicing, which is a method to identify the relevant entities of the program according to data and control dependenci...
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Program dependency graphs (PDG) facilitate program analysis and related applications such as program slicing, which is a method to identify the relevant entities of the program according to data and control dependencies. In the past, PDGs and program slicing were mostly developed for (conventional) imperative programs. Recently, the object-oriented (OO) paradigm has gained momentum and popularity. The OO paradigm introduces the features of object abstraction, encapsulation, inheritance and polymorphism to programs, but is not considered in PDGs and program slicing. In this paper, we present an object-oriented dependency graph (ODG) to represent the structure of OO programs. The ODG is defined based on a property multi-digraph that is extended from a directed graph by augmenting multiple edge types, vertex properties and property relations. With these extensions, the ODG can avoid specious dependencies due to object encapsulation. Based on the ODG, a program slicing method for OO software is developed. Besides data and control dependencies, dependencies caused by OO features are taken into consideration in our slicing method. Through the ODG, the slicing method can be applied to facilitate the understanding, debugging and maintenance of OO software in the same way that traditional program slicing methods do.
This paper targets engineers and practitioners who want a simple procedure to compute the mean performance measures of the Batch Markovian Arrival process (BMAP/G/1) queueing system when the parameter matrices order i...
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This paper discusses an object-based software development and maintenance environment, Opusdei, built and used for several years at Hitachi softwareengineering (HSK - Since 1994, University of Minnesota has been invo...
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This paper discusses an object-based software development and maintenance environment, Opusdei, built and used for several years at Hitachi softwareengineering (HSK - Since 1994, University of Minnesota has been involved in the Opusdei project.) Industrial software is usually large, has many versions, undergoes frequent changes, and is developed concurrently by multiple programmers. Opusdei was designed to handle various problems inherent in such industrial environments. In Opusdei, all information needed for development is stored using an uniform representation in a central repository, and the various documentation and views of the software artifacts can be generated automatically using the tool repository. Opusdeis’ innovative capabilities are 1) uniform software artifacts representation 2) inter-relation and traceability maintenance among software artifacts 3) tools coordination and tool integration using tool composition scenarios 4) automatic documentation and versioning control. Tool coordination and composition has been discussed in the literature as a possible way to make software development environments more intelligent. Opusdei provides a uniform representation of software artifacts and tools which is an essential first step in addressing the issues of tool coordination and composition. Opusdei has been operational for several years and has been used in many large software development projects. The productivity gain reported for some of these projects, by using Opusdei ranged from 50–90%.
One of the major concerns of any maintenance organization is to understand and estimate the cost of maintenance releases of software systems. Planning the next release so as to maximize the increase in functionality a...
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ISBN:
(纸本)9780818672460
One of the major concerns of any maintenance organization is to understand and estimate the cost of maintenance releases of software systems. Planning the next release so as to maximize the increase in functionality and the improvement in quality are vital to successful maintenance management. The objective of the paper is to present the results of a case study in which an incremental approach was used to better understand the effort distribution of releases and build a predictive effort model for software maintenance releases. The study was conducted in the Flight Dynamics Division (FDD) of NASA Goddard Space Flight Center (GSFC). The paper presents three main results: (1) a predictive effort model developed for the FDD's software maintenance release process, (2) measurement-based lessons learned about the maintenance process in the FDD, (3) a set of lessons learned about the establishment of a measurement-based software maintenance improvement program. In addition, this study provides insights and guidelines for obtaining similar results in other maintenance organizations.
Views are an established technique for restructuring and repartitioning the format of data, classes, and schemata so that applications can customize shared data objects without affecting other applications' percep...
For systems based on Bayesian networks, evidence is used to compute posterior probabilities for some hypotheses. Sensitivity analysis is concerned with questions on how sensitive the conclusion is to the evidence prov...
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Writing software to control networks is important and difficult. It must be efficient, reliable, and flexible. Conduits+ is a framework for network software that has been used to implement the signalling system of a m...
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作者：
MORIMOTO, KIRIGUCHI, HAOE, JMemberFaculty of Engineering
Tokushima University Tokushima Japan 770 Jun-ichi Aoe received his B.E. and M.E. degrees in 1974 and 1976
respectively from Tokushima Univ. where he was a Research Associate in the Dept. Inf. Fac. Eng. received his Ph.D. later. Presently Prof. Intel. Inf. He is engaged in research on compiler generation system and highly efficient pattern matching algorithm. Presently interestedin natural language processing especially understanding system. He is the author of “Computer Algorithms- Key Search Strategies” IEEE CS Press. Best Author Award 1992 Inf. Proc. Soc. Member Inf. Proc. Soc. Jap. Soc. Artif. Intel. Jap. Software Sci. Jap. Jap. Soc. Mach. Transl. IEEE ACM and AAAI.
The trie has the feature that the retrieval can be executed with the character symbols composing the key as the unit, and a high-speed retrieval is realized independently of the total number of keys. Consequently, it ...
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The trie has the feature that the retrieval can be executed with the character symbols composing the key as the unit, and a high-speed retrieval is realized independently of the total number of keys. Consequently, it used frequently in the search of the natural language dictionary and in other problems. A problem, however, is that the number of trie states increases with the enlargement of the key set, which necessitates a larger memory capacity. To remedy this point, DAWG (Directed Acyclic Word-Graph) is proposed, where the common suffix of the tries is compressed. Then, a new problem arises in that the record information cannot be determined uniquely for the key. For this problem, this paper introduces a new structure, where the number of states is reduced by merging the common suffixes of the tries, while determining uniquely the record information for the key. The algorithm for retrieval, insertion and deletion of the key is proposed for the structure. In the proposed method, the set of keys is represented using two tries. One of the tries memorizes the prefix of the minimum length that can discriminate uniquely between the key from other keys. The other trie stores the suffixes of the remaining keys in order to merge the common suffix. A simulation is executed for various sets of keys such as Chinese character called Kanji, alphabets and Japanese Katakana characters, and it is seen that the number of states is reduced by approximately 30 to 65 percent for the key set of 50,000 words, compared to the ordinary trie.
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