Experience-sampling procedures enable researchers to record the momentary thoughts, feelings, and actions of people in daily life. The authors explain how palmtop computers have expanded the repertoire of experience-sampling techniques and reduced or eliminated some traditional problems with pen-and-paper methods. As a running example, they illustrate the capabilities of the Experience Sampling Program (ESP), their configurable, freely distributable software environment for designing and running experience-sampling studies on Palm Pilots and Windows CE palmtops.

The Stokes formulation for representing polarized light is discussed along with the classical measurement method for determining the Stokes polarization parameters. The limitations of this method are noted, and we consider the rotating quarter-waveplate method, which avoids the limitations of the classical method and allows a curve fitting algorithm to be used to determine the Stokes parameters. The quarter-waveplate method is attractive because of its accuracy and simplicity and can be implemented in an undergraduate or graduate optics course with a minimum amount of equipment.

Although event-based software integration is one of the most prevalent approaches to loose integration, no consistent model for describing it exists. As a result, there is no uniform way to discuss event-based integration, compare approaches and implementations, specify new eventbased approaches, or match user requirements with the capabilities of event-based integration systems. We attempt to address these shortcomings by specifying a generic framework for event-based integration, the EBI framework, that provides a flexible, object-oriented model for discussing and comparing event-based integration approaches. The EBI framework can model dynamic and static specification, composition, and decomposition and can be instantiated to describe the features of most common event-based integration approaches. We demonstrate how to use the framework as a reference model by comparing and contrasting three wellknown integration systems: FIELD, Polylith, and CORBA.

Interoperability is a fundamental concern in many areas of software engineering, such as software reuse or infrastructures for software development environments. Of particular interest to software engineers are the interoperability problems arising in polylingual software systems. The defining characteristic of polylingual systems is their focus on uniform interaction among a set of components written in two or more different languages.Existing approaches to support for interoperability are inadequate because they lack seamlessness: that is, they generally force software developers to compensate explicitly for the existence of multiple languages or the crossing of language boundaries. In this paper we first discuss some foundations for polylingual interoperability, then review and assess existing approaches. We then outline PolySPIN, an approach in which interoperability can be made transparent and existing systems can be made to interoperate with no visible modifications. We also describe PolySPINner, our prototype implementation of a toolset providing automated support for PolySPIN. We illustrate the advantages of our approach by applying it to an example problem and comparing PolySPIN's ease of use with that of an alternative, CORBA-style approach.