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41.
Steve Phelps Peter McBurney Simon Parsons 《Autonomous Agents and Multi-Agent Systems》2010,21(2):237-264
The advent of large-scale distributed systems poses unique engineering challenges. In open systems such as the internet it
is not possible to prescribe the behaviour of all of the components of the system in advance. Rather, we attempt to design
infrastructure, such as network protocols, in such a way that the overall system is robust despite the fact that numerous
arbitrary, non-certified, third-party components can connect to our system. Economists have long understood this issue, since
it is analogous to the design of the rules governing auctions and other marketplaces, in which we attempt to achieve socially-desirable
outcomes despite the impossibility of prescribing the exact behaviour of the market participants, who may attempt to subvert
the market for their own personal gain. This field is known as “mechanism design”: the science of designing rules of a game
to achieve a specific outcome, even though each participant may be self-interested. Although it originated in economics, mechanism
design has become an important foundation of multi-agent systems (MAS) research. In a traditional mechanism design problem,
analytical methods are used to prove that agents’ game-theoretically optimal strategies lead to socially desirable outcomes.
In many scenarios, traditional mechanism design and auction theory yield clear-cut results; however, there are many situations
in which the underlying assumptions of the theory are violated due to the messiness of the real-world. In this paper we review
alternative approaches to mechanism design which treat it as an engineering problem and bring to bear engineering design principles, viz.: iterative step-wise refinement of solutions, and satisficing
instead of optimization in the face of intractable complexity. We categorize these approaches under the banner of evolutionary mechanism design. 相似文献
42.
43.
Mobile robotic systems must sense constraints imposed by a dynamically changing environment and predictably react to those changes in real-time. Complexity arises in mobile robotic systems because the computing platform travels through the environment with which the system is interacting. These systems have spatio-temporal requirements in the sense that correct behavior is defined in terms of both space and time. The focus of this paper is mobile robotic platforms that must sense their environment and avoid obstacles as they navigate from one point to another. We present a design and analysis methodology for these platforms that integrates spatio-temporal attributes with fixed priority real-time scheduling through the use of zone and processing window abstractions. 相似文献
44.
Investment in information technology is steadily increasing, but many organizations find it difficult to formally assess the value of IT investments because the latter are often incorporated into broad management initiatives. the authors believe that the results of the research study reported on here can help firms to develop a better understanding of the dynamic relationship between IT investment and performance at both the firm and industry levels of analysis. This study clearly demonstrates the importance of adopting an organizational change perspective when assessing the impact of IT investment on firm performance. 相似文献
45.
Securing Wireless Mesh Networks 总被引:1,自引:0,他引:1
Now found in domestic, commercial, industrial, military, and healthcare applications, wireless networks are becoming ubiquitous. Wireless mesh networks (WMNs) combine the robustness and performance of conventional infrastructure networks with the large service area and self-organizing and self-healing properties of mobile ad hoc networks. In this article, the authors consider the problem of ensuring security in WMNs, introduce the IEEE 802.11s draft standard, and discuss the open security threats faced at the network and data-link layers. 相似文献
46.
Matt Jones Steve Jones Gareth Bradley Nigel Warren David Bainbridge Geoff Holmes 《Personal and Ubiquitous Computing》2008,12(7):513-525
Listening to music on personal, digital devices whilst mobile is an enjoyable, everyday activity. We explore a scheme for
exploiting this practice to immerse listeners in navigation cues. Our prototype, ONTRACK, continuously adapts audio, modifying
the spatial balance and volume to lead listeners to their target destination. First we report on an initial lab-based evaluation
that demonstrated the approach’s efficacy: users were able to complete tasks within a reasonable time and their subjective
feedback was positive. Encouraged by these results we constructed a handheld prototype. Here, we discuss this implementation
and the results of field-trials. These indicate that even with a low-fidelity realisation of the concept, users can quite
effectively navigate complicated routes.
相似文献
Matt Jones (Corresponding author)Email: |
Steve JonesEmail: |
Gareth BradleyEmail: |
Nigel WarrenEmail: |
David BainbridgeEmail: |
Geoff HolmesEmail: |
47.
Steve Whittaker Simon Tucker Kumutha Swampillai Rachel Laban 《Personal and Ubiquitous Computing》2008,12(3):197-221
Although many recent systems have been built to support Information Capture and Retrieval (ICR), these have not generally
been successful. This paper presents studies that evaluate two different hypotheses for this failure, firstly that systems
fail to address user needs and secondly that they provide only rudimentary support for ICR. Having first presented a taxonomy
of different systems built to support ICR, we then describe a study that attempts to identify user needs for ICR. On the basis
of that study we carried out two user-oriented evaluations. In the first, we carried out a task-based evaluation of a state-of-the-art
ICR system, finding that it failed to provide users with abstract ways to view meetings data, and did not present users with
information categories that they considered to be important. In a second study, we introduce a new method for comparative
evaluation of different techniques for accessing meetings data. The second study showed that simple interface techniques that
extracted key information from meetings were effective in allowing users to extract gist from meetings data. We conclude with
a discussion of outstanding issues and future directions for ICR research. 相似文献
48.
Structured decomposition of adaptive applications 总被引:1,自引:0,他引:1
49.
Guo Y Hsu S Sawhney HS Kumar R Shan Y 《IEEE transactions on pattern analysis and machine intelligence》2007,29(5):824-839
This paper addresses the problem of matching vehicles across multiple sightings under variations in illumination and camera poses. Since multiple observations of a vehicle are separated in large temporal and/or spatial gaps, thus prohibiting the use of standard frame-to-frame data association, we employ features extracted over a sequence during one time interval as a vehicle fingerprint that is used to compute the likelihood that two or more sequence observations are from the same or different vehicles. Furthermore, since our domain is aerial video tracking, in order to deal with poor image quality and large resolution and quality variations, our approach employs robust alignment and match measures for different stages of vehicle matching. Most notably, we employ a heterogeneous collection of features such as lines, points, and regions in an integrated matching framework. Heterogeneous features are shown to be important. Line and point features provide accurate localization and are employed for robust alignment across disparate views. The challenges of change in pose, aspect, and appearances across two disparate observations are handled by combining a novel feature-based quasi-rigid alignment with flexible matching between two or more sequences. However, since lines and points are relatively sparse, they are not adequate to delineate the object and provide a comprehensive matching set that covers the complete object. Region features provide a high degree of coverage and are employed for continuous frames to provide a delineation of the vehicle region for subsequent generation of a match measure. Our approach reliably delineates objects by representing regions as robust blob features and matching multiple regions to multiple regions using Earth Mover's Distance (EMD). Extensive experimentation under a variety of real-world scenarios and over hundreds of thousands of Confirmatory Identification (CID) trails has demonstrated about 95 percent accuracy in vehicle reacquisition with both visible and Infrared (IR) imaging cameras. 相似文献
50.
Formal Analysis of Multiparty Contract Signing 总被引:1,自引:0,他引:1
We analyze the multiparty contract-signing protocols of Garay and MacKenzie (GM) and of Baum and Waidner (BW). We use a finite-state tool, Mocha, which allows specification of protocol properties in a branching-time temporal logic with game semantics. While our analysis does not reveal any errors in the BW protocol, in the GM protocol we discover serious problems with fairness for four signers and an oversight regarding abuse-freeness for three signers. We propose a complete revision of the GM subprotocols in order to restore fairness. 相似文献