Cohesion has been a topic of interest since structured design in the 1970’s. Cohesion may also be viewed as a characterization of a system attribute. Today, there are numerous researchers continuing this work into object-oriented designs. Most of the current research has focused on the interaction of methods within a class, the inter-method cohesion. In this paper, we consider both the inter-method cohesion and the intra-method cohesion of a class. We have utilized the concept of program slice (Weiser, 1981) and have extended Functional Cohesion (Bieman & Ott, 1994) to devise a new intra-method cohesion metric, ITRA-C, for measuring cohesion of each method within the class. This intra-method cohesion is based on the notion of effects and chaining in an effect-slice. We further combine the (inter-method, intra-method)-tuple into one combined Class Cohesion, which provides a quick view of bands of cohesion for categorizing classes.

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One of the basic problems in distributed databases is how to efficiently perform distributed joins. Spatial databases are particularly appropriate for distribution, but we need special techniques to deal with spatial data efficiently.In this work we study the distributed spatial join problem and how to perform this operation efficiently. We develop cost models for estimating the cost of this operation. We study the issues involved in optimizing it and develop specific techniques using R-Trees. Our techniques outperform other widely-used approaches for this operation.

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Security topics have been taught for some time at universities. The most common approach has been to teach a required topic, and then introduce a security module later in the course. We have been promoting the notion of teaching security at the same time as main course's material. We found that this helps students to accept the idea of writing secure code at an early stage and encourages them to focus on the security issues before they start coding. We proposed teaching secure practices as the default model presented to the students, facilitating the adoption of those practices. Over a period of one year we promoted the concept among our colleagues both in our school and at teaching conferences. This paper is a report that shows where we are one year after of implementation of Teaching with Security in Mind.