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Shape and material parameters have major influence on the performance of electromagnetic components. Optimization of these parameters is therefore vital in electromagnetic design. Reduction of the radar cross section (RCS) for aircraft and frequency selective surfaces are two well known examples. Shape and materials optimization is performed for different scatterers in 2D.

Continuum design sensitivities for microwave problems are applied for the gradient‐based optimization of scatterers' shape and material parameters. The goal function is chosen to be an average of the monostatic RCS for a sector of incident angles over a frequency band. Numerical tests are presented for 2D scatterers and, specifically, a perfectly electrically conducting scatterer and an absorber on the front edge of an airplane wing are considered. The results are compared with theoretical findings and results in the open literature.

It is demonstrated that a dense frequency sampling of the goal function over a wide frequency band relaxes the requirements on the angular resolution. The broad band requirements on the RCS also avoids corrugations without the resorting to regularization methods and penalty terms added to the goal function. The optimization algorithm refines, in a small number of iterations, the initial geometry of the scatterer to an optimized design with strongly reduced RCS.

Shape and material parameters have major influence on the performance of electromagnetic components. Optimization of these parameters for scatterers demonstrates that a densely evaluated goal function over a broad frequency band has the advantages of: lowering the requirements on angular resolution; avoiding corrugations; and regularizing the problem by the broad frequency band requirements which often are naturally included in the performance specification of electromagnetic devices.

Reviews Milton and Rose D. Friedman’s, Two Lucky People: Memoirs, University of Chicago Press, Chicago, 1998, $35 (£24.95), ISBN 0‐226‐26414‐9. Focuses on how the memoirs illuminate the main contributions Friedman has made to political economy and the economics literature.

The purpose of this paper is to explore the field of learning, learning style, meta‐cognition, strategies and teaching by classifying different levels of the learning process. The paper aims to present an attempt to identify how students' awareness of learning style and teachers' matched instruction might affect students' learning and motivation.

The paper is a conceptual paper in which a theoretical framework built on empirical research was identified by connecting and systemizing different parts of the learning process.

The paper finds that teaching based on individual learning styles is an effective way to ensure students' achievement and motivation. Awareness of learning styles, it is argued, influences meta‐cognition and choice of relevant learning strategies. Consciousness of own improvement provides students with new perspectives of their learning potential. Such positive academic experiences may enhance self‐efficacy.

The paper provides useful information on unraveling concepts, methods and effects which can aid students, teachers and researchers in understanding, evaluating and monitoring learning, thus having practical implications for promoting lifelong learning, self‐efficacy and salutogenesis.

Disclosure research has argued that visuals are increasingly used in annual reports as a way to increase readability of the annual report, but comparatively little is known about of diagrams compared to graphs and photographs. The purpose of this paper is to provide a historical account of visuals use in corporate disclosure, with an emphasis on diagrams, to show changes from the 1940s until present-day reporting.

Visual research methods were applied to analyze how diagrams, photographs and graphs were used in 69 annual reports of the Swedish telecom company Ericsson.

Photographs have been used with increasing frequency since the 1950s. Graph and diagram use has increased significantly since the 1990s while photograph use remained stable, suggesting that graphs and diagrams increasingly complement photographs for visually representing the organization in corporate disclosure. Factors explaining the case company’s development include both internal (performance, individual preferences, shifting from a manufacturing-based strategy to a service-based strategy) and external (legislation, transformation of the telecom industry).

Visual elements in annual reports are increasingly oriented toward immaterial representations of the organization’s standings and identity and diagrams are increasingly used and contribute to this. This finding motivates further research about diagram use in corporate communication, such as how different diagram types convey accounting messages, and whether diagrams serve as impression management devices. For regulators, it will be important to follow the emerging trend of diagram use, since it is becoming part of reporting practice.

Two key factors in the success of general-purpose computing platforms are the creation of a technical standards architecture and managing an ecosystem of third-party suppliers of complementary products. Here, we examine Symbian Ltd., a startup firm that developed a strong technical architecture and broad range of third-party complements with its Symbian OS for smartphones. Symbian was shipped in nearly 450 million mobile phones from 2000 to 2010, making it the most popular smartphone platform during that period. However, its technical and market control of the platform were limited by its customers, particularly Nokia. From 2007 onward, Symbian lost market share and developer loyalty to the new iPhone and Android platforms, leading to the extinction of the company and eventually its platform. Together, this suggests lessons for the evolution of a complex ecosystem, and the impact of asymmetric dependencies and divided leadership upon ecosystem success.

There are several ways to implement and work with the Balanced Scorecard (BSC). The company Ericsson Data AB was one of the pioneers in employing the BSC in Sweden. As early adopters, they were interested in obtaining an evaluation performed by external researchers. We were fortunate to have that opportunity. During the autumn of 1998, Majvor Karlsson and Ellen Sharma had full access to the developmental department dealing with the implementation of BSC at the company. The present article is based on interviews with managers and developers with the aim to determine how the BSC was implemented and how it functions in the day‐to‐day life of the company. The BSC model introduced in Ericsson was given the name Cockpit. As one might expect, implementing BSC requires a great deal of time and energy. We found that it resembles the process in other organisational changes as well. In our research, we found that there were many aspects of the implementation of BSC with which we could interpret and explain our observations with the help of theories of organisational change. Our findings led us to formulate a theory concerning the implementation process of the BSC. It was a relief to discover that we could use a method that allowed us to listen and learn from the persons involved in the implementation process at Ericsson Data.

Ericsson Information Systems. L. M. Ericsson, the Swedish telecommunications giant, has just formed a new company — Ericsson Information Systems (EIS) — which will compete in the information technology market. The new company has been created out of two Ericsson divisions and Datasaab, a Swedish computer firm, which Ericsson bought a year ago. EIS is expected to continue marketing Datasaab's successful terminal and minicomputer, but in addition will develop and sell products for the private and business markets, particularly integrated information systems, office automation systems and PABXs.

Rather than organize as traditional firms, many of today’s companies organize as platforms that sit at the nexus of multiple exchange and production relationships. This chapter considers a most basic question of organization in platform contexts: the choice of boundaries. Herein, I investigate how classical economic theories of firm boundaries apply to platform-based organization and empirically study how executives made boundary choices in response to changing market and technical challenges in the early mobile computing industry (the predecessor to today’s smartphones). Rather than a strict or unavoidable tradeoff between “openness-versus-control,” most successful platform owners chose their boundaries in a way to simultaneously open-up to outside developers while maintaining coordination across the entire system.