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261.
The model selection paradigm is one of the focused themes within decision science. This paper addresses the consistent solution of model selection issue on the basis of the fuzzy axiomatic design (FAD) methodology. Moreover, the developed FAD–based model selection interface (FAD–MSI) is performed over the critical ship management processes in order to assign suitable (multiple criteria decision-making) MCDM techniques even if commonly utilized hybrid approaches. The outcomes of this study encourage the maritime practitioners for the further researches towards analytical modelling of ship management processes. 相似文献
262.
Tiina Komulainen Francis J. Doyle III Ari Rantala Sirkka-Liisa Jämsä-Jounela 《Journal of Process Control》2009,19(1):2-15
A two level control strategy that stabilizes and optimizes the production of an industrial copper solvent extraction process is presented. The stabilizing layer consists of a multi-input–multi-output controller or two single-input–single-output controllers with additional four feedforward compensators that regulate the flow rates in the copper solvent extraction process. The optimization layer consists of an optimizer that maximizes the production of the copper solvent extraction process and gives setpoints to the controllers at the stabilizing level. The mechanistic plant models, verified with industrial data, are linearized by identifying first and higher order transfer function models from simulated PRBS data. On the basis of the linear models, the interactions of the controlled variables, and the pairing of the controlled and manipulated variables are studied and the optimizer and the controllers designed. The control strategy employing two PI-control loops or a model predictive controller and additionally four feedforward control loops is successfully tested against simulated disturbances and setpoint changes. The control strategy is also compared to the data collected from the industrial plant under manual control. With this two level control strategy the production of the copper solvent extraction process is increased by 3–5% and the process variation is decreased by 70–90% compared to the manual operation of the case industrial plant. The results gained in simulation environment are successful and encouraging for further testing in an industrial plant. 相似文献
263.
Anne Köpsel Päivi Majaranta Poika Isokoski Anke Huckauf 《Behaviour & Information Technology》2016,35(12):1044-1062
Modern interaction techniques like non-intrusive gestures provide means for interacting with distant displays and smart objects without touching them. We were interested in the effects of feedback modality (auditory, haptic or visual) and its combined effect with input modality on user performance and experience in such interactions. Therefore, we conducted two exploratory experiments where numbers were entered, either by gaze or hand, using gestures composed of four stroke elements (up, down, left and right). In Experiment 1, a simple feedback was given on each stroke during the motor action of gesturing: an audible click, a haptic tap or a visual flash. In Experiment 2, a semantic feedback was given on the final gesture: the executed number was spoken, coded by haptic taps or shown as text. With simultaneous simple feedback in Experiment 1, performance with hand input was slower but more accurate than with gaze input. With semantic feedback in Experiment 2, however, hand input was only slower. Effects of feedback modality were of minor importance; nevertheless, semantic haptic feedback in Experiment 2 showed to be useless at least without extensive training. Error patterns differed between both input modes, but again not dependent on feedback modality. Taken together, the results show that in designing gestural systems, choosing a feedback modality can be given a low priority; it can be chosen according to the task, context and user preferences. 相似文献
264.
265.
We consider broadcasting in random d-regular graphs by using a simple modification of the random phone call model introduced by Karp et al. (Proceedings of the FOCS ’00, 2000). In the phone call model, in every time step, each node calls a randomly chosen neighbour to establish a communication channel to this node. The communication channels can then be used bi-directionally to transmit messages. We show that, if we allow every node to choose four distinct neighbours instead of one, then the average number of message transmissions per node required to broadcast a message efficiently decreases exponentially. Formally, we present an algorithm that has time complexity \(O(\log n)\) and uses \(O(n\log \log n)\) transmissions per message. In contrast, we show for the standard model that every distributed algorithm in a restricted address-oblivious model that broadcasts a message in time \(O(\log n)\) requires \(\Omega (n \log n{/} \log d)\) message transmissions. Our algorithm efficiently handles limited communication failures, only requires rough estimates of the number of nodes, and is robust against limited changes in the size of the network. Our results have applications in peer-to-peer networks and replicated databases. 相似文献
266.
This paper develops and tests a motivational model to explain the overall continuance intention to use computers and smartphones. Based on survey data from 192 undergraduate students, structural equation modeling analysis is used to report: (1) the independent effect of intrinsic motivation on the continuance intention to use computers and smartphones; (2) the independent effect of extrinsic motivation on the continuance intention to use computers but not smartphones; (3) intrinsic motivation mediating the effect of extrinsic motivation on the continuance intention to use computers; (4) the independent effect of technology cognizance on the continuance intention to use computers but not smartphones; (5) intrinsic motivation positively influencing extrinsic motivation and technology cognizance, with respect to both devices. This research contributes to an improved understanding of the independent and interrelated effects of intrinsic and extrinsic motivations to use technological devices. The findings have important implications for theory and practice regarding the overall use of technology. 相似文献
267.
Mikko Kurimo Seppo Enarvi Ottokar Tilk Matti Varjokallio André Mansikkaniemi Tanel Alumäe 《Language Resources and Evaluation》2017,51(4):961-987
One particular problem in large vocabulary continuous speech recognition for low-resourced languages is finding relevant training data for the statistical language models. Large amount of data is required, because models should estimate the probability for all possible word sequences. For Finnish, Estonian and the other fenno-ugric languages a special problem with the data is the huge amount of different word forms that are common in normal speech. The same problem exists also in other language technology applications such as machine translation, information retrieval, and in some extent also in other morphologically rich languages. In this paper we present methods and evaluations in four recent language modeling topics: selecting conversational data from the Internet, adapting models for foreign words, multi-domain and adapted neural network language modeling, and decoding with subword units. Our evaluations show that the same methods work in more than one language and that they scale down to smaller data resources. 相似文献
268.
269.
270.
Jens Jägersküpper 《Algorithmica》2011,59(3):409-424
In their seminal article Droste, Jansen, and Wegener (Theor. Comput. Sci. 276:51–82, 2002) consider a basic direct-search heuristic with a global search operator, namely the so-called (1+1) Evolutionary Algorithm
((1+1) EA). They present the first theoretical analysis of the (1+1) EA’s expected runtime for the class of linear functions
over the search space {0,1}
n
. In a rather long and involved proof they show that, for any linear function, the expected runtime is O(nlog n), i.e., that there are two constants c and n′ such that, for n≥n′, the expected number of iterations until a global optimum is generated is bounded above by c⋅nlog 2
n. However, neither c nor n′ are specified—they would be pretty large. Here we reconsider this optimization scenario to demonstrate the potential of
an analytical method that makes use of the distribution of the evolving candidate solution over the search space {0,1}
n
. Actually, an invariance property of this distribution is proved, which is then used to obtain a significantly improved bound
on the drift, namely the expected change of a potential function, here the number of bits set correctly. Finally, this better
estimate of the drift enables an upper bound on the expected number of iterations of 3.8nlog 2
n+7.6log 2
n for n≥2. 相似文献