The aim of this article is to improve our understanding of user-centered design (UCD) adoption and provide accordingly useful advice to the UCD community. UCD adoption was investigated through a Web survey. The results show that the early involvement of UCD practitioners in the product life cycle is more frequent compared to 10 years ago. It is also true that the methods and the techniques employed have shifted their focus from summative evaluation to rapid development cycles and from quantitative to qualitative evaluation methods. Based on the survey, there are several organizational factors UCD practitioners and their management should consider. UCD should be part of the business strategy and supported by higher management. Usability goals must be set through competitive analysis and practitioners should be rewarded if goals are reached or exceeded. For bespoke systems, usability goals should be explicitly discussed with the customer. Special attention should be paid to communication inside and outside the company so as to clarify the outcomes and benefits of the UCD approach.

The primary contribution of this paper is investigating how the User Centered Design approach is integrated into the industry. Employing a structured web-survey, targeted to the usability practitioners, we find out that UCD is particularly employed in big companies, but with a relatively low ratio: practitioners represent less than one percent of the company employees. User interviews and both low and high fidelity prototyping are the most frequently used techniques. We eventually validate our hypothesis that UCD integration is facilitated by factors related to management support, infrastructure and communication; companies interested in producing better usable and fit-for-use products should take all of these issues into serious consideration.

This article outlines a semantic approach to the logics of unknown truths, and the logic of false beliefs, using neighborhood structures, giving results on soundness, completeness, and expressivity. Relational semantics for the logics of unknown truths are also addressed, specically the conditions under which sound axiomatizations of these logics might be obtained from their normal counterparts, and the relationship between refexive insensitive logics (RI-logics) and logics containing the provability operator as the primary modal operator.

Abstract. We present the method introduced by Neeman of generalized side conditions with two types of models. We then discuss some applications: a variation of the Friedman-Mitchell poset for adding a club with finite conditions, the consistency of the existence of an ω 2 increasing chain in (ω ω1 1 , < fin ), originally proved by Koszmider, and the existence of a thin very tall superatomic Boolean algebra, originally proved by Baumgartner-Shelah. We expect that the present method will have many more applications.

We analyze a class of modal logics rendered insensitive to reflexivity by way of a modification to the semantic definition of the modal operator. We explore the extent to which these logics can be characterized, and prove a general completeness theorem on the basis of a translation between normal modal logics and their reflexive-insensitive counterparts. Lastly, we provide a sufficient semantic condition describing when a similarly general soundness result is also available.

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In this paper we extend to non-classical set theories the standard strategy of proving independence using Boolean-valued models. This extension is provided by means of a new technique that, combining algebras (by taking their product), is able to provide product-algebra-valued models of set theories. In this paper we also provide applications of this new technique by showing that: (1) we can import the classical independence results to non-classical set theory (as an example we prove the independence of $\mathsf {CH}$ ); and (2) we can provide new independence results. We end by discussing the role of non-classical algebra-valued models for the debate between universists and multiversists and by arguing that non-classical models should be included as legitimate members of the multiverse.

The aim of this paper is to reflect on the evaluation of DELTA, a distributed learning resources repository. We employed scenarios and claims analysis techniques so as to derive assessable evaluation goals. These goals were related to three quality dimensions: quality of use, pedagogical effectiveness and acceptability for the end-users. We employed a set of six quantitative and qualitative research methods and triangulated the results obtained. The results demonstrate that DELTA met around half of the evaluation goals. This project was an opportunity to reflect on the degree of fitness for purpose of our methods. Two of the qualitative methods employed (user diaries and pedagogy workshop) were particularly effective in the triangulation process.