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71.
Fuzzy quality function deployment (QFD) has been extensively used for translating customer requirements (CRs) into product design requirements (DRs) in fuzzy environments. Existing approaches, however, for rating technical importance of DRs in fuzzy environments are found problematic, either incorrect or inappropriate. This paper investigates how the technical importance of DRs can be correctly rated in fuzzy environments. A pair of nonlinear programming models and two equivalent pairs of linear programming models are developed, respectively, to rate the technical importance of DRs. The developed models are examined and illustrated with two numerical examples. 相似文献
72.
In the frequency allocation problem, we are given a mobile telephone network, whose geographical coverage area is divided
into cells, wherein phone calls are serviced by assigning frequencies to them so that no two calls emanating from the same
or neighboring cells are assigned the same frequency. The problem is to use the frequencies efficiently, i.e., minimize the
span of frequencies used. The frequency allocation problem can be regarded as a multicoloring problem on a weighted hexagonal
graph. In this paper, we give a 1-local asymptotic 4/3-competitive distributed algorithm for multicoloring a triangle-free
hexagonal graph, which is a special case of hexagonal graph. Based on this result, we then propose a 1-local asymptotic13/9-competitive
algorithm for multicoloring the (general-case) hexagonal graph, thereby improving the previous 1-local 3/2-competitive algorithm.
A preliminary version of this paper appeared in the Proceedings of the 13th Annual International Computing and Combinatorics
Conference (COCOON 2007), LNCS 4598, pp. 526–536.
Y. Zhang research was supported by European Regional Development Fund (ERDF).
F.Y.L. Chin research was supported by Hong Kong RGC Grant HKU-7113/07E.
H. Zhu research was supported by National Natural Science Fund (grant #60496321). 相似文献
73.
Failure mode and effects analysis (FMEA) is a methodology to evaluate a system, design, process or service for possible ways in which failures (problems, errors, risks and concerns) can occur. It is a group decision function and cannot be done on an individual basis. The FMEA team often demonstrates different opinions and knowledge from one team member to another and produces different types of assessment information such as complete and incomplete, precise and imprecise and known and unknown because of its cross-functional and multidisciplinary nature. These different types of information are very difficult to incorporate into the FMEA by the traditional risk priority number (RPN) model and fuzzy rule-based approximate reasoning methodologies. In this paper we present an FMEA using the evidential reasoning (ER) approach, a newly developed methodology for multiple attribute decision analysis. The proposed FMEA is then illustrated with an application to a fishing vessel. As is illustrated by the numerical example, the proposed FMEA can well capture FMEA team members’ diversity opinions and prioritize failure modes under different types of uncertainties. 相似文献
74.
75.
Mei Kum Khaw Chin Hong Ooi Faisal Mohd-Yasin Anh V. Nguyen Geoffrey M. Evans Nam-Trung Nguyen 《Microfluidics and nanofluidics》2017,21(6):110
This paper reports the dynamic behaviour of a magnetically actuated floating liquid marble by analysing the oscillation of the marble. A liquid marble is a liquid droplet coated with hydrophobic powder. Magnetite particles inside the marble make it magnetic. The marble floats on a carrier liquid that contains aqueous glycerol of various concentrations. A permanent magnet located under the carrier liquid drives the floating marble with the initial velocity. Stopping the magnet abruptly causes the marble to oscillate around its final position for a few seconds. The oscillation was recorded and analysed using customised image processing and evaluation software. The damped harmonic motion model was then applied to the data and tested. Subsequently, critical parameters of the system such as the initial displacement, friction correction factor, the apparent frequency and the spring constant were determined and discussed. The simple experimental set-up and convenient theoretical approach allow us to characterise the marble motion under the influence of a magnet with good accuracy. 相似文献
76.
Lum Angeline Su Lyn Chiew Thiam Kian Ng Chirk Jenn Lee Yew Kong Lee Ping Yein Teo Chin Hai 《Universal Access in the Information Society》2017,16(3):775-791
Universal Access in the Information Society - In recent years, researchers have attempted to shift patient decision aids (PDAs) from paper-based to web-based to increase its accessibility. Insulin... 相似文献
77.
A common computer-based collaborative learning approach is to simply introduce contemporary computermediated communication technology into the classroom to support prescribed learning activities. This approach assumes that all students collaborate in similar ways and that presentday technology is sufficient to accommodate all collaboration forms. This view is superficial and limiting. Students collaborate in different ways at different levels on different learning activities. A more detailed articulation of collaboration in learning is crucial to understanding and extending the pedagogical capabilities and usefulness of collaborative technologies. A model is presented for a more finely articulated form of analysis that enumerates types of collaborative learning activities and evaluates how these activities may be supported through different design options. The analysis is based on actual classroom scenarios and the collaboration requirements that emerge from them. The authors have successfully applied this analysis model in the design of a computer-based collaborative learning environment for science education. 相似文献
78.
Strategies for Expressing Concise, Helpful Answers 总被引:2,自引:0,他引:2
David N. Chin 《Artificial Intelligence Review》2000,14(4-5):333-350
An intelligent help system needs to take into account the user's knowledgewhen formulating answers. This allows the system to provide more conciseanswers, because it can avoid telling users things that they already know.Since these concise answers concentrate exclusively on pertinent newinformation, they are also easier to understand. Information about theuser's knowledge also allows the system to take advantage of the user'sprior knowledge in formulating explanations. The system can provide betteranswers by referring to the user's prior knowledge in the explanation(e.g., through use of similes). This process of refining answers is calledanswer expression.The process of answer expression has been implemented in the UCExpresscomponent of UC (UNIX Consultant), a natural language system that helps theuser solve problems in using the UNIX operating system. UCExpress separatesanswer expression into two phases: pruning and formatting.In the pruning phase, subconcepts of the answer are pruned by being markedas already known by the user (and hence do not need to be generated), ormarked as candidates for generating anaphora or ellipsis (since they arepart of the conversational context). In the formatting phase, UCExpressuses information about the user's prior domain knowledge to select amongspecialized expository formats,such as similes and examples, for expressing information to the user. Theseformats allow UCExpress to present different types of information to theuser in a clear, concise manner. The result of UCExpress' answer expressionprocess is an internal form that a tactical level generator can easily useto produce good English. 相似文献
79.
Chin‐Yang Lee Chi‐Hung Liu Chih‐Wei Chen Saodo Miki Huang‐Ming Philip Chen Shermann Lin Po‐Hua Su Chein‐Dhau Lee 《Journal of the Society for Information Display》2008,16(1):71-75
Abstract— Novel anode layer plasma within minimum chamber space was developed for non‐contact alignment process. The plasma‐treated polyimide (PI) surface showed no particle contamination and no micro‐scratches. Surface morphology was investigated by using scanning electron microscope (SEM), an atomic force microscope (AFM), and X‐ray photoemission spectroscopy. The different oxygen‐to‐carbon ratio ([O]/[C] ratio) for XPS spectra indicated a composition change after plasma treatment. Surface pretilt angles were varied from 0 to 2.1° under different plasma exposure times. Finally, a prototype 20.8‐in. QXGA IPS‐mode gray‐scale medical liquid‐crystal display was successfully demonstrated with high contrast ratio, excellent uniformity, and wide viewing angle using this new plasma‐beam‐alignment technique. 相似文献
80.
Empirical Evaluation of User Models and User-Adapted Systems 总被引:5,自引:0,他引:5
Empirical evaluations are needed to determine which users are helped or hindered by user-adapted interaction in user modeling systems. A review of past UMUAI articles reveals insufficient empirical evaluations, but an encouraging upward trend. Rules of thumb for experimental design, useful tests for covariates, and common threats to experimental validity are presented. Reporting standards including effect size and power are proposed. 相似文献