Knowledge-Based Systems. Overview and Selected Examples

The Advanced Computer Applications (ACA) project builds on IIASA's traditional strength in the methodological foundations of operations research and applied systems analysis, and its rich experience in numerous application areas including the environment, technology and risk. The ACA group draws on this infrastructure and combines it with elements of AI and advanced information and computer technology to create expert systems that have practical applications. By emphasizing a directly understandable problem representation, based on symbolic simulation and dynamic color graphics, and the user interface as a key element of interactive decision support systems, models of complex processes are made understandable and available to non-technical users. Several completely externally-funded research and development projects in the field of model-based decision support and applied Artificial Intelligence (AI) are currently under way, e.g., "Expert Systems for Integrated Development: A Case Study of Shanxi Province, The People's Republic of China." This paper gives an overview of some of the expert systems that have been considered, compared or assessed during the course of our research, and a brief introduction to some of our related in-house research topics

Conditions of Uncertainty: The Social and Political Dimensions of Risk Management in the Transition to the Biomedical Era of HIV Prevention

The HIV prevention field in Canada has failed to achieve a stabilising point, a lack of consensus on the effectiveness of risk management strategies, in its third decade, the transition to the biomedical era of HIV prevention. Under these conditions of uncertainty we have witnessed epistemic and social and political uncertainties proliferate. Experts debate long-standing and emerging prevention strategies. Newly produced knowledge complicates our understanding of gay male HIV prevention but often lacks appropriate validity and generalizability. Governing practices are implemented to respond to this knowledge, but in conflicting ways. For everyday social actors, these uncertainties morph into complicated forms of experiential uncertainty. I first present this dissertation as a work of critical social science on HIV. Drawing from critical studies on risk and uncertainty I then produce an original analytic framework termed the uncertainty triad. I then examine biomedical and public health research and critical perspectives on gay male HIV prevention, arguing that the field cultivates uncertainty to “beat-up” the epidemic. I then present data from 33 in-depth interviews conducted with young HIV-negative gay men to discuss their everyday confrontations with serostatus uncertainty (an inability to confirm one’s HIV-negativity). This is a move away from analysing motivations for condomless anal sex and focusing exclusively on “high risk men.” To avoid exclusively tapping into the HIV epistemic community, the interviewees hadn’t previously participated in a research interview about HIV and had no regular involvement with an AIDS service organisation. I then present an original theory on risk disposition, which investigates a social actor’s processes of risk reflexivity and his tolerance to serostatus uncertainty. Social conditions affecting the experiences of health maintenance, institutional navigation and sexual practice can shape tolerance to serostatus uncertainty by minimising or fostering anxiety. Drawing on the notion of sexual practice over sexual behaviour, I then examine HIV-negative gay men’s confrontations with HIV-related ethico-political challenges such as HIV stigma, serosorting and the criminalisation of HIV non-disclosure. I argue that biomedical optimism does not necessarily lead to the abandonment of condoms among HIV-negative gay men and that many remain sceptical of the prevention benefits of HIV treatments