Olli Karonen

What makes expert systems survive over 10 years—empirical evaluation of several engineering applications

Abstract This case study analyzes eight expert system applications that have successfully been in industrial use for a long time. We have personally been involved in the development of these applications and are thus in a good position to analyze what is important for a successful application and what kind of mistakes can be made. Since the development of the applications started in 1986–1990 and some of them are still in use we are able to observe what has happened to those applications during their lifetime. Our key observations are related to the scope of the applications, to the trade-off between usability and automation, to the role of human experts in the use and development of expert systems, on the technical solutions used, on aspects of the operation of the expert system and on the similarities between expert systems and information systems. The key findings are expressed as 20 hypotheses for successful expert systems. The support of each application to the hypotheses is discussed.

Cooperation Incentives and Enablers for Wireless Peers in Heterogeneous Networks

Various incentive schemes have been proposed to force or encourage peers to contribute their resources to peer-to-peer networks. Such schemes are typically designed for peers with fixed Internet connections and do not take the special properties of wireless peers into account. In this paper we propose a P2P credit system especially targeted for the cases where mobile devices join P2P networks. Instead of limiting the incentive and reputation mechanisms to a single device our scheme encompasses all the connected devices of a user. We discuss the limitations of todays incentive schemes from the wireless devices point of view, present the P2P credit system concept and highlight its operation with a number of use cases. Through mathematical analysis we illustrate the potential of the solution.

Sharing the Experience with Mobile Video: A Student Community Trial

To understand the technical feasibility and user perception of mobile video, we conducted a two-week trial where a student community used mobile phone and web technologies to share the events of a campus festival. The questions we investigated included the capability of contemporary smart phones to capture and share the events via real time and stored video; the usage patterns that arise within mobile video community; and the social connections between shooters and viewers. Outcomes on the technical level indicate that challenges remain. The bandwidth of 3G cellular connections limits the quality of live videos and video transfer via public WLAN networks is unreliable causing lost connections. The best results today can be achieved by sending the captured videos from mobile phones to the server in the background and providing video-on-demand rather than live video service. The observed consumption patterns show that freshness of the videos is the least important selection factor while manual and automatic textual tagging is important. Seamless integration of video sharing to camera application would improve the user experience.