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In this paper we develop a formal basis for research into the reliability aspects of transaction processing in multidatabase systems. We define a new correctness notion called global committability (GC) for the correct unilateral commit and retry recovery of global transactions in an autonomous MDBS environment. This notion facilitates to ensure the isolation property of global transactions when the retry approach is applied. The formalization work illustrates that conventional serializability (SR) notion and recoverability (RC) notion are not sufficient to specify a correct execution (i.e., isolated execution and recovery) of global transactions when the unilateral commit and the retry recovery are used to ensure the atomicity of global transactions. This work is significant because the unilateral commit and the retry recovery is an attractive complementary means to the undo recovery (whose correct schedule is specified by the conventional RC notion) for advanced transaction applications with characteristics of site autonomy and long-lived execution. Index Terms - Multidatabases, transaction management, global transactions, local transactions, unilateral commit, retry recovery, serializability, recoverability, global committability.

Describes an empirical study of the skills assessment of software practitioners. Data collection; Data analysis; Data representation; Follow-up reassessment; Critical skills relating to object-oriented and client-server technologies; Improvement of productivity during downturns by increasing working effectiveness; Need for software developers to keep pace with software technology.

Describes how a generic communication framework can serve as a testbed for the specification, verification and execution of distributed communication protocols. Coordination kernel with shared write-once objects; Primitives for coordination; Concurrency through process creation; Architectures; Noncompensatable transactions; Internal dependencies.

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The recent advances in laboratory technologies have resulted in a wealth of chemical and biological data. The rapid proliferation of a vast amount of data has led to a set of cheminformatics and bioinformatics applications that manipulate dynamic, heterogeneous, and massive data. An example of such application in the pharmaceutical industry is the computational process involved in the early discovery of lead drug candidates for a given target disease. In this paper, an efficient implementation of a drug candidate database is presented and evaluated. This study shows that high performance data access can be achieved through proper choices of data representation, database schema design, and parallel processing techniques.