Online trendy topics detection in microblogs with selective user monitoring under cost constraints

As microblog services such as Twitter become a fast and convenient communication approach, identification of trendy topics in microblog services has great academic and business value. However detecting trendy topics is very challenging due to huge number of users and short-text posts in microblog diffusion networks. In this paper we introduce a trendy topics detection system under computation and communication resource constraints. In stark contrast to retrieving and processing the whole microblog contents, we develop an idea of selecting a small set of microblog users and processing their posts to achieve an overall acceptable trendy topic coverage, without exceeding resource budget for detection. We formulate the selection operation of these subset users as mixed-integer optimization problems, and develop heuristic algorithms to compute their approximate solutions. The proposed system is evaluated with real-time test data retrieved from Sina Weibo, the dominant microblog service provider in China. It's shown that by monitoring 500 out of 1.6 million microblog users and tracking their microposts (about 15,000 daily) with our system, nearly 65% trendy topics can be detected, while on average 5 hours earlier before they appear in Sina Weibo official trends.

Knowledge-based system for casting process selection

Design of casting entails the knowledge of various interacting factors that are unique to casting process, and, quite often, product designers do not have the required foundry-specific knowledge. Casting designers normally have to liaise with casting experts in order to ensure the product designed is castable and the optimum casting method is selected. This two-way communication results in long design lead times, and lack of it can easily lead to incorrect casting design. A computer-based system at the discretion of a design engineer can, however, alleviate this problem and enhance the prospect of casting design for manufacture. This paper proposes a knowledge-based expert system approach to assist casting product designers in selecting the most suitable casting process for specified casting design requirements, during the design phase of product manufacture. A prototype expert system has been developed, based on production rules knowledge representation technique. The proposed system consists of a number of autonomous but interconnected levels, each dealing with a specific group of factors, namely, casting alloy, shape and complexity parameters, accuracy requirements and comparative costs, based on production quantity. The user interface has been so designed to allow the user to have a clear view of how casting design parameters affect the selection of various casting processes at each level; if necessary, the appropriate design changes can be made to facilitate the castability of the product being designed, or to suit the design to a preferred casting method.

Divided care and the Third Way:user involvement in statutory and voluntary sector cancer services

In health care, as in much of the public sphere, the voluntary sector is playing an increasingly large role in the funding, provision and delivery of services and nowhere is this more apparent than in cancer care. Simultaneously the growth of privatisation, marketisation and consumerism has engendered a rise in the promotion of 'user involvement' in health care. These changes in the organisation and delivery of health care, in part inspired by the 'Third Way' and the promotion of public and citizen participation, are particularly apparent in the British National Health Service. This paper presents initial findings from a three-year study of user involvement in cancer services. Using both case study and survey data, we explore the variation in the definition, aims, usefulness and mechanisms for involving users in the evaluation and development of cancer services across three Health Authorities in South West England. The findings have important implications for understanding shifts in power, autonomy and responsibility between patients, carers, clinicians and health service managers. The absence of any common definition of user involvement or its purpose underlines the limited trust between the different actors in the system and highlights the potentially negative impact of a Third Way health service.

Selecting the 'invisible' user interface development tool

Developers of interactive software are confronted by an increasing variety of software tools to help engineer the interactive aspects of software applications. Typically resorting to ad hoc means of tool selection, developers are often dissatisfied with their chosen tool on account of the fact that the tool lacks required functionality or does not fit seamlessly within the context in which it is to be used. This paper describes a system for evaluating the suitability of user interface development tools for use in software development organisations and projects such that the selected tool appears ‘invisible’ within its anticipated context of use. The paper also outlines and presents the results of an informal empirical study and a series of observational case studies of the system.

Expert System for Decision-Making Problem in Economics

An expert system (ES) is a class of computer programs developed by researchers in artificial intelligence. In essence, they are programs made up of a set of rules that analyze information about a specific class of problems, as well as provide analysis of the problems, and, depending upon their design, recommend a course of user action in order to implement corrections. ES are computerized tools designed to enhance the quality and availability of knowledge required by decision makers in a wide range of industries. Decision-making is important for the financial institutions involved due to the high level of risk associated with wrong decisions. The process of making decision is complex and unstructured. The existing models for decision-making do not capture the learned knowledge well enough. In this study, we analyze the beneficial aspects of using ES for decision- making process.