According to W. Edwards Deming, American companies require nothing less than a transformation of management style and of governmental relations with industry. In Out of the Crisis, originally published in 1982, Deming offers a theory of management based on his famous 14 Points for Management. Management's failure to plan for the future, he claims, brings about loss of market, which brings about loss of jobs. Management must be judged not only by the quarterly dividend, but by innovative plans to stay in business, protect investment, ensure future dividends, and provide more jobs through improved product and service. In simple, direct language, he explains the principles of management transformation and how to apply them.

Out of the Crisis

Turing Lecture from the winners of the 2007 ACM A.M. Turing Award. In 1981, Edmund M. Clarke and E. Allen Emerson, working in the USA, and Joseph Sifakis working independently in France, authored seminal papers that founded what has become the highly successful field of model checking. This verification technology provides an algorithmic means of determining whether an abstract model---representing, for example, a hardware or software design---satisfies a formal specification expressed as a temporal logic (TL) formula. Moreover, if the property does not hold, the method identifies a counterexample execution that shows the source of the problem. The progression of model checking to the point where it can be successfully used for complex systems has required the development of sophisticated means of coping with what is known as the state explosion problem. Great strides have been made on this problem over the past 28 years by what is now a very large international research community. As a result many major hardware and software companies are beginning to use model checking in practice. Examples of its use include the verification of VLSI circuits, communication protocols, software device drivers, real-time embedded systems, and security algorithms. The work of Clarke, Emerson, and Sifakis continues to be central to the success of this research area. Their work over the years has led to the creation of new logics for specification, new verification algorithms, and surprising theoretical results. Model checking tools, created by both academic and industrial teams, have resulted in an entirely novel approach to verification and test case generation. This approach, for example, often enables engineers in the electronics industry to design complex systems with considerable assurance regarding the correctness of their initial designs. Model checking promises to have an even greater impact on the hardware and software industries in the future. ---Moshe Y. Vardi, Editor-in-Chief

Model checking

物件導向軟體之架構(Object-Oriented Software Construction)探討

In both e-business and e-science, we often need to integrate services across distributed, heterogeneous, dynamic “virtual organizations” formed from the disparate resources within a single enterprise and/or from external resource sharing and service provider relationships. This integration can be technically challenging because of the need to achieve various qualities of service when running on top of different native platforms. We present an Open Grid Services Architecture that addresses these challenges. Building on concepts and technologies from the Grid and Web services communities, this architecture defines a uniform exposed service semantics (the Grid service); defines standard mechanisms for creating, naming, and discovering transient Grid service instances; provides location transparency and multiple protocol bindings for service instances; and supports integration with underlying native platform facilities. The Open Grid Services Architecture also defines, in terms of Web Services Description Language (WSDL) interfaces and associated conventions, mechanisms required for creating and composing sophisticated distributed systems, including lifetime management, change management, and notification. Service bindings can support reliable invocation, authentication, authorization, and delegation, if required. Our presentation complements an earlier foundational article, “The Anatomy of the Grid,” by describing how Grid mechanisms can implement a service-oriented architecture, explaining how Grid functionality can be incorporated into a Web services framework, and illustrating how our architecture can be applied within commercial computing as a basis for distributed system integration—within and across organizational domains. This is a DRAFT document and continues to be revised. The latest version can be found at http://www.globus.org/research/papers/ogsa.pdf. Please send comments to foster@mcs.anl.gov, carl@isi.edu, jnick@us.ibm.com, tuecke@mcs.anl.gov Physiology of the Grid 2

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The Physiology of the Grid An Open Grid Services Architecture for Distributed Systems Integration

This paper describes the symbolic execution of programs. Instead of supplying the normal inputs to a program (e.g. numbers) one supplies symbols representing arbitrary values. The execution proceeds as in a normal execution except that values may be symbolic formulas over the input symbols. The difficult, yet interesting issues arise during the symbolic execution of conditional branch type statements. A particular system called EFFIGY which provides symbolic execution for program testing and debugging is also described. It interpretively executes programs written in a simple PL/I style programming language. It includes many standard debugging features, the ability to manage and to prove things about symbolic expressions, a simple program testing manager, and a program verifier. A brief discussion of the relationship between symbolic execution and program proving is also included.

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Symbolic execution and program testing

This paper describes a system that attempts to generate test data for programs written in ANSI Fortran. Given a path, the system symbolically executes the path and creates a set of constraints on the program's input variables. If the set of constraints is linear, linear programming techniques are employed to obtain a solution. A solution to the set of constraints is test data that will drive execution down the given path. If it can be determined that the set of constraints is inconsistent, then the given path is shown to be nonexecutable. To increase the chance of detecting some of the more common programming errors, artificial constraints are temporarily created that simulate error conditions and then an attempt is made to solve each augmented set of constraints. A symbolic representation of the program's output variables in terms of the program's input variables is also created. The symbolic representation is in a human readable form that facilitates error detection as well as being a possible aid in assertion generation and automatic program documentation.

A System to Generate Test Data and Symbolically Execute Programs

Welcome to the silver anniversary of the International Conference on Software Engineering! Managing the complexity of modern software systems is without question a grand challenge. It is therefore fitting that, inspired by the view of Mount Hood in Portland, Oregon, the theme for this year's meeting is: Scaling New Heights.ICSE, the premier conference for software engineering, brings together world leaders in software engineering research, practice, and education to present and discuss the most recent advances, trends, and concerns in this ever expanding and critical field. This year's Software Engineering Week, May 3 to 10, 2003, consists of the main ICSE conference and an interesting array of tutorials, workshops, and related events associated or co-located with ICSE.

Proceedings of the 25th International Conference on Software Engineering

A formal, general model of program dependences is presented and used to evaluate several dependence-based software testing, debugging, and maintenance techniques Two generalizations of control and data flow dependence, called weak and strong syntactic dependence, are introduced and related to a concept called semantic dependence Semantic dependence models the ability of a program statement to affect the execution behavior of other statements It is shown that weak syntactic dependence is a necessary but not sufficient condition for semantic dependence and that strong syntactic dependence is necessary but not sufficient condition for a restricted form of semantic dependence that is finitely demonstrated These results are used to support some proposed uses of program dependences, to controvert others, and to suggest new uses >

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A formal model of program dependences and its implications for software testing, debugging, and maintenance

Early software environments have supported a narrow range of activities (programming environments) or else been restricted to a single “hard-wired” software development process. The Arcadia research project is investigating the construction of software environments that are tightly integrated, yet flexible and extensible enough to support experimentation with alternative software processes and tools. This has led us to view an environment as being composed of two distinct, cooperating parts. One is the variant part, consisting of process programs and the tools and objects used and defined by those programs. The other is the fixed part, or infrastructure, supporting creation, execution, and change to the constituents of the variant part. The major components of the infrastructure are a process programming language and interpreter, object management system, and user interface management system. Process programming facilitates precise definition and automated support of software development and maintenance activities. The object management system provides typing, relationships, persistence, distribution and concurrency control capabilities. The user interface management system mediates communication between human users and executing processes, providing pleasant and uniform access to all facilities of the environment. Research in each of these areas and the interaction among them is described.

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Foundations for the Arcadia environment architecture

The authors report on the results of their evaluation of path-selection criteria based on data-flow relationships. They show how these criteria relate to each other, thereby demonstrating some of their strengths and weaknesses. A subsumption hierarchy showing their relationship is presented. It is shown that one of the major weaknesses of all the criteria is that they are based solely on syntactic information and do not consider semantic issues such as infeasible paths. The authors discuss the infeasible-path problem as well as other issues that must be considered in order to evaluate these criteria more meaningfully and to formulate a more effective path-selection criterion. >

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Lori A. Clarke

Papers

A System to Generate Test Data and Symbolically Execute Programs

Proceedings of the 25th International Conference on Software Engineering

A formal model of program dependences and its implications for software testing, debugging, and maintenance

Foundations for the Arcadia environment architecture

A formal evaluation of data flow path selection criteria