J. Bailey

The service sector accounts for most of the world's economic activity, but it's the least-studied part of the economy. A service system comprises people and technologies that adaptively compute and adjust to a system's changing value of knowledge. A science of service systems could provide theory and practice around service innovation

One of the primary motivations behind autonomic computing (AC) is the problem of administrating highly complex systems. AC seeks to solve this problem through increased automation, relieving system administrators of many burdensome activities. However, the AC strategy of managing complexity through automation runs the risk of making management harder. We performed field studies of current administrator work practices to inform the design of AC in order to ensure that it simplifies system management. In this paper, we analyze what system administrators do in terms of three important activities: rehearsal and planning, maintaining situation awareness, and managing multitasking, interruptions and diversions. We provide guidelines for constructing AC environments that support these activities.

The Advanced Train Control System (ATCS) communications system, which provides for the information flow in the North American ATCS, is presented in the context of the overall ATCS plan. The major components and basic operation of ATCS are described. The features, functions, and connectivity of the nodes in the communication system are defined. The communications system is based on the OSI (Open Systems Interconnection) model; and the protocols used are described with particular emphasis on the radio data link. Special features of the communications system, including a description of how vehicles are tracked, are included.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The American Association of Railroads (AAR) and the Association of Canadian Railroads (ACR) jointly initiated an implementation study of the Advanced Train Control System (ATCS) to improve the efficiency and economics of railroad operations. The data link between locomotives and the dispatcher is identified as a vital link within ATCS. The design of this link includes considerations on modulation, data rates, protocol, access scheme, forward error control, and their impact on spectral needs. The steps taken toward specifying ATCS radio-link design parameters to meet operational requirements of railroads are described. Extensive computer simulations to evaluate suitability of the chosen system parameters such as data rate, access scheme, and coding were made under some realistic mobile channel conditions. Results of this design exercise are summarized.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Autonomic Computing lays out a vision of information technology in which systems manage themselves based on policies. As a result, policies are the new currency of interaction between people and computers, creating a new paradigm for interaction with autonomic systems. In this paradigm, interaction shifts (1) from low-level to high-level monitoring and control and (2) from manually performing actions to delegating tasks to automation. In this paper, we report an experimental study comparing and contrasting manual interaction to policy-based interaction to manage a simulated e-commerce website. In this study, we investigated issues related to human expertise and policy representation. Our results suggest that effective policy-based interaction depends both on the level of detail of the policies and on the experience of the system supervisor. Our results show an overall benefit of policy-based interaction, as measured by business and technology-oriented metrics. Performance was significantly better with policy-based interaction following expertise gained through manual interaction. Performance with manual interaction was marginally worse after policy-based interaction, suggesting the classic out-of-the-loop problem. In addition, highly detailed policy representations marginally improved performance for technology-oriented metrics but did not yield significant differences for business-oriented metrics.