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1.
The paper addresses an issue that must be resolved to produce a scientifically sound and practically useful reference model for intelligent multimedia presentation systems (IMP systems), namely that of providing, from the point of view of Human-Computer Interaction (HCI), a systematic understanding of the types of output information to be presented by IMP systems. The term ‘medium’, as it is used in the context of multimedia systems, is too coarse-grained for distinguishing between different types of output information. The paper introduces the notion of (representational) ‘modalities’ to enable sufficiently fine-grained distinctions to be made. For the term itself to be meaningful, ‘multimodal’ presentations must be composed of unimodal representations. In the approach presented, unimodal representations are defined from a small number of basic properties whose combinations specify the ‘generic’ level of a taxonomy of unimodal output modalities. Additional basic property distinctions serve to generate the more fine-grained ‘atomic’ and ‘sub-atomic’ levels in a hierarchical fashion. The taxonomy is set up with the aim of satisfying four basic requirements, viz. completeness, orthogonality, relevance and intuitiveness. A concluding discussion illustrates the practical use of the taxonomy.  相似文献   

2.
Dandan  Xiaohua  Ivan   《Computer Communications》2007,30(18):3627-3643
Location service provides position of mobile destination to source node to enable geo-routing. In existing quorum-based location service protocols, destination node registers its location along a ‘column’ while source node makes a query along a ‘row’. Grid and quorum-based location service is based on division of network into square grids, and selecting ‘leader’ location server node in each grid. Location updates, leader reelection and information transfer are performed whenever destination and leader nodes are moving to a different grid. We propose here to apply connected dominating sets (DS) as an alternative to grids. We also improved basic quorum, and applied on DS-quorum (DS based quorum) better criterion for triggering local information exchanges and global location updates, by meeting two criteria: certain distance movement and certain number of observed link changes with (DS) nodes. Backbones created by DS nodes (using 1-hop neighborhood information) are small size, do not have a parameter like grid size, and preserve network connectivity without the help of other nodes. Location updates and destination searches are restricted to backbone nodes. Both methods use ‘hello’ messages to learn neighbors. While this suffices to construct DS, grid leader (re)election requires additional messages. Simulation results show that using DS as backbone for quorum construction is superior to using grid as backbone or no backbone at all. The proposed DS-quorum location service can achieve higher (or similar) success rate with much less communication overhead than grid-based approaches.  相似文献   

3.
In order to perform business modelling as apart of information systems development, there is a need for frameworks and methods. The paper proposes a framework for business interaction based on a language/action perspective. The framework is an architecture of five generic layers. The first layer concept is ‘business act’, which functions as the basic unit of analysis. The following four layer concepts are ‘action pair’, ‘exchange’, ‘business transaction’, and ‘transaction group’. The framework is inspired by a similar framework constructed by Weigand et al. The paper makes a critical examination of this framework as a basis for the proposed framework.  相似文献   

4.
Containing the ‘outsider’ threat to the information systems of organisations as well as recognising the disruptive potential of ‘insiders’ are fundamentals of security management. However, the recent development of public–private partnerships in the UK requires a reassessment of the continuing utility of such dualities. This paper draws upon a sociological understanding of the complexities of organisational practices as well as a grounded case study of the implementation of the NHS ‘Choose and book’ service across both public and private healthcare organisations in order to challenge these essentialist forms of sociotechnical analysis. The paper proposes a sociomaterial understanding of information systems and organisational dynamics that does not seek to separate out distinct ‘human’ and ‘technical’ information security risks. Rather, it asserts that the organisational outcomes of the introduction of new information systems are necessarily emergent and contingent, and it is with these indeterminate realities that security analysts have to engage.  相似文献   

5.
We show that the Lyapunov function used in backstepping feedback designs for uncertain nonlinear systems leads to unnecessarily ‘hard’ control laws having undesirable high-gain properties. We present a new Lyapunov function and use it to design ‘softer’ control laws which exhibit the high-gain properties to a much lesser extent. We show that the ‘soft’ designs eliminate the chattering exhibited by the ‘hard’ designs and achieve the same or better performance with less control effort.  相似文献   

6.
A knowledge base containing incomplete information in the form of disjunctions and negative information shows difficulties regarding the update operators. In this paper simple and straightforward definitions are given for an ‘adding’ operator (‘+’) and a ‘removing’ operator (‘−’) using Hebrand models.  相似文献   

7.
Current state-of-the-art security systems incorporate ‘passive’ and/or ‘human’ elements, the effectiveness of which can only be measured by their ability to ‘deter’ intruders. However, rapidly changing economic and cultural conditions have weakened the strengths associated with such systems. In the not too distant future, the need for an ‘active’ security system will become necessary in order to reduce the onslaught of crime.

This paper presents a conceptual basis for the incorporation of artificial intelligence concepts in the design and implementation of ‘active’ security systems. Specifically, the paper discusses issues pertaining to a real-time model for visual perception and tracking of possible intruders.  相似文献   


8.
The European automotive industry requires frequent interaction and transfer of data between geographically dispersed designers and engineers at all stages of the product introduction process. The RACE CAR project identified and demonstrated Integrated Broadband Communications (IBC)-supported applications to support this process and improve competitiveness. User requirements for workstation-based, multi-media facilities including conferencing were identified. Two experiments were designed to investigate the role of face-to-face video and the means by which participants organise and control their interactions. These are critical issues in the multi-cultural, international environment of the European automotive industry. In the first experiment groups of three users solved a cooperative, screen-based, object manipulation task supported by different levels of communication. ‘Linked computers plus an audio link’ resulted in significantly faster completion times than either ‘audio alone’ or ‘linked computer plus audio and face-to-face video’. ‘Linked computers plus audio’ was also perceived as the most effective communications media. The passage of cursor via verbal agreement was successfully managed. Video was generally considered beneficial for initial introductions, assessing understanding and facilitating a stronger feeling of group identity.

In the second experiment, subjects were grouped under ‘chaired’ or ‘free-for-all’ conditions and linked via (1) audio and linked computers or (2) audio, linked computers and face-to-face video. The task was similar to Experiment 1 and attempts to introduce contention were made through adding hidden, sub-goals. The task took significantly less time to complete in the ‘video chaired’ condition than the ‘non-video chaired’ or ‘video free-for-all’ conditions. This suggests that video has an important role in enabling a chairperson to control the meeting. Contention was not successfully achieved.

The results of the experiments suggest face-to-face video may be useful in chaired meetings and to develop ‘team’ feeling. A free-for-all method of control passing was seen as most appropriate although problems in achieving contention in Experiment 2 meant the impact of disagreement was not fully investigated. The results are discussed in relation to the European automotive industry and areas for further study identified. Relevance to industry

The European automotive industry, which maintains distinct engineering functions in disparate countries, is striving to reduce the length of its design life cycle by improving communications between designers and engineers. The studies described in this paper provide information of use to the developers and procurers of systems intended to support this process. In particular issues relating to the relevance of face-to-face video and use of control mechanisms for co-operative computer-mediated work.  相似文献   


9.
BP is one of the largest energy companies in the world with 2003 revenues of $233 billion. In this paper, we analyse its use of an innovative ‘multi-enterprise asset management system’ that supports and enables the asset management strategy of BP's exploration and production division on the UK continental shelf (UKCS). The analysis focuses on how BP connects its business processes with over 1500 suppliers to co-ordinate the maintenance, operation and repair of specialised exploration and production equipment. The systems strategy is novel because it takes the enterprise computing concept and implements it across organisational boundaries—hence the term ‘multi-enterprise system’. This use of a shared system with all of its suppliers is distinctive from the most common way of connecting with economic partners which is to use shared data systems based on common data standards and communication technologies such as EDI and more recently XML-based systems within vertical industries such as RosettaNet. The design of the multi-enterprise system is based on a sophisticated business process management system called Maximo and this is used to illustrate the systems design aspect of the overall information system in the broader contexts of business strategy and information technology infrastructure.  相似文献   

10.
The paper deals with the optimal sensor location problem associated with minimax filtering for linear distributed parameter systems under the moving sensors. The problem of optimal choice of a measurement trajectory is treated here as an H-optimal control one under phase constraints with the objective to minimize a given ‘weak’ performance index under ‘worst’ possible disturbances. Existence of a solution to such a problem is established for the case of quadratic constraints on the disturbances and necessary conditions for optimally are derived on the basis of constructing a sequence of suboptimal solutions associated, in turn, with a sequence of finite-dimensional maximum principles.  相似文献   

11.
There is a growing information gap between the development of advanced human-machine systems, and the availability of human factors design criteria that can be applied during their design process. Despite increased interest in the development of human factors design guidelines, there also remains considerable uncertainty and concern regarding the actual utility of such information. Indeed, many existing human factors reference materials have been criticized by designers for being ‘too wordy’, ‘too general’, and ‘too hard to understand’. The development of clear, relevant, and useful human factors guidelines requires a judicious mix of science and art to overcome such criticisms. Specifically, while a number of empirical and systematic methods can be productively applied to their development, the final design guidelines will always represent a subjective integration of user requirements, design constraints, available information, and expert judgement. This paper summarizes procedures and heuristics associated with both the science and the art components of human factors design guideline development.  相似文献   

12.
This paper proposes a research direction to study the development of ‘artificial social intelligence’ of autonomous robots which should result in ‘individualized robot societies’. The approach is highly inspired by the ‘social intelligence hypothesis’, derived from the investigation of primate societies, suggesting that primate intelligence originally evolved to solve social problems and was only later extended to problems outside the social domain. We suggest that it might be a general principle in the evolution of intelligence, applicable to both natural and artificial systems. Arguments are presented why the investigation of social intelligence for artifacts is not only an interesting research issue for the study of biological principles, but may be a necessary prerequisite for those scenarios in which autonomous robots are integrated into human societies, interacting and communicating both with humans and with each other. As a starting point to study experimentally the development of robots' ‘social relationships’, the investigation of collection and use of body images by means of imitation is proposed. A specific experimental setup which we use to test the theoretical considerations is described. The paper outlines in what kind of applications and for what kind of robot group structures social intelligence might be advantageous.  相似文献   

13.
14.
Current computer systems providing consumer services seem to be designed primarily on ‘technology-oriented’ thinking, based on the ‘efficiency’ and the operating methods of the computer. To be of benefit to a wider variety of consumers, the system design may have to reflect a more ‘consumer-oriented’ approach, based on factors such as the needs, preferences, skills and knowledge of the user. This article demonstrates the differences between user evaluations of two computer systems designed to help in house-hunting, modelled on (a) consumer-oriented, and (b) technology-oriented approaches. Although particularly relevant to consumer systems, the article may have important implications for consumer and public services in general.  相似文献   

15.
The new HCI? navigation of information space   总被引:4,自引:0,他引:4  
David Benyon 《Knowledge》2001,14(8):425-430
When we use the term ‘human–computer interaction’ (HCI), the image that is conjured up is of a person sitting at a visual display unit staring in at the world of ‘information’; the person is very much outside the space of information. But when we think of other activities such as going shopping, having a meeting or driving across town, we do not think of the person as outside this space. On the contrary, we see the person as inside a space of activities, surrounded by, and interacting with, assorted artefacts and people. Navigation of Information Space is an alternative conceptualisation of HCI that sees people as existing inside information spaces. Looking at HCI in this way means looking at HCI design as the creation of information spaces. This paper explores these ideas in more detail, arguing that Navigation of Information Space is not just a metaphor for HCI; it is a ‘paradigm shift’. The paper illustrates how Semiotics has informed this conception and discusses why such a paradigm shift is needed.  相似文献   

16.
Buried stormwater pipe networks play a key role in surface drainage systems for urban areas of Australia. The pipe networks are designed to convey water from rainfall and surface runoff only and do not transport sewage. The deterioration of stormwater pipes is commonly graded into structural and serviceability condition using CCTV inspection data in order to recognize two different deterioration processes and consequences. This study investigated the application of neural networks modelling (NNM) in predicting serviceability deterioration that is associated with reductions of pipe diameter until a complete blockage. The outcomes of the NNM are predictive serviceability condition for individual pipes, which is essential for planning proactive maintenance programs, and ranking of pipe factors that potentially contribute to the serviceability deterioration. In this study the Bayesian weight estimation using Markov Chain Monte Carlo simulation was used for calibrating the NNM on a case study in order to account for the uncertainty often encountered in NNM's calibration using conventional back-propagation weight estimation. The performance and the ranked factors obtained from the NNM were also compared against a classical model using multiple discrimination analysis (MDA). The results showed that the predictive performance of the NNM using Bayesian weight estimation is better than that of the NNM using conventional backpropagation and MDA model. Furthermore, among nine input factors, ‘pipe age’ and ‘location’ appeared insignificant whilst ‘pipe size’, ‘slope’, ‘the number of trees’ and ‘climatic condition’ were found consistently important over both models for serviceability deterioration process. The remaining three factors namely, ‘structure’, ‘soil’ and ‘buried depth’ might be redundant factors. A better and more consistent data collection regime may help to improve the predictive performance of the NNM and identify the significant factors.  相似文献   

17.
A technique for the selection of the best set of test features for checkout or go-no-go test of a complex electro-hydraulic servo system from input-output measurements is presented. The first step is to establish checkout tolerance bands on the system response. Then the measurement set based on gain and phase which would best discriminate between the ‘healthy’ and ‘sick’ systems is selected from an initially large set of sampled frequencies via an optimization procedure in which the feature efficiency vector is introduced to add or discard features until a satisfactory set is obtained. Finally the selected feature sets are assessed for effectiveness via a ‘goodness’ criterion.  相似文献   

18.
The use of a touch-screen public access health information system was evaluated by monitoring system usage, by interviews with an opportunistic sample of 90 users and by other surveys.

To get the largest number of users, such a system needs to be sited in a highly visible setting where there are lots of people passing. For most people, privacy does not appear to be a problem. However, some groups may require more privacy and when siting in ‘quieter’ places, such as a library this may be more important than in busier anonymous places, or in places where health is a ‘natural’ topic of interest. Waiting rooms may not be the best sites.  相似文献   


19.
The project described is concerned with the development of a practical system for interpreting carotid angiograms. The general requirements of such a system are identified and some of the design considerations are discussed. The analysis strategies and types of knowledge used by an expert in recognizing and naming vessels and categorizing abnormalities on a single-plane angiogram are described- Two distinct types of knowledge are identified: ‘facts’ knowledge which is drawn from various areas of science, and ‘strategy’ knowledge which determines how the facts should be used. It is suggested that confidence parameters should be associated with each type of knowledge and these should be used in the control of the analysis of an angiogram. The ‘facts’ and ‘strategy’ knowledge bases have a hierarchical structure which, if exploited, would enable the system to be easily adapted for use in other application areas.  相似文献   

20.
Discrete Event Systems (DES) are a special type of dynamic system. The ‘state’ of these systems changes at discrete instants in time and the term ‘event’ represents the occurrence of discontinuous change (at possibly unknown intervals). Different Discrete Event Systems models are currently used for specification, verification, synthesis as well as for analysis and evaluation of different qualitative and quantitative properties of existing physical systems. The focus of this paper is the presentation of the automata and formal language model for DES introduced by Ramadge and Wonham and its application to the domain of mobile manipulator/observer agents. We demonstrate the feasibility of the DES framework for modeling, analysis and synthesis of some visually guided behaviors of agents engaged in navigational tasks and address synchronization issues between different components of the system. The use of DES formalism allows us to synthesize complex behaviors in a systematic fashion and guarantee their controllability.  相似文献   

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