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91.
92.
GSA: A Gravitational Search Algorithm 总被引:13,自引:0,他引:13
In recent years, various heuristic optimization methods have been developed. Many of these methods are inspired by swarm behaviors in nature. In this paper, a new optimization algorithm based on the law of gravity and mass interactions is introduced. In the proposed algorithm, the searcher agents are a collection of masses which interact with each other based on the Newtonian gravity and the laws of motion. The proposed method has been compared with some well-known heuristic search methods. The obtained results confirm the high performance of the proposed method in solving various nonlinear functions. 相似文献
93.
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95.
《国际互联网参考资料服务季刊》2013,18(2):11-20
Abstract The Information Services Department at the Washington, DC law firm, Dickstein Shapiro Morin & Oshinsky, decided in 1995 to provide firmwide access to the Internet. Two separate World Wide Web home pages would be created to meet the divergent needs of the Marketing Department and the information resource requirements of the attorneys, who would be using the Internet for research. In the course of developing Internet pages for the firm, the Library began working in conjunction with attorneys in various practice sections to locate and create Internet resources. The cooperation between attorneys and the Libraiy has led to Internet pages of hypertext linked resources for each specific practice section within the firm. Furthermore, some of the pages of resources have evolved into home pages for the various sections. 相似文献
96.
《Ergonomics》2012,55(6):519-530
‘Shrinking targets’ are targets whose size diminishes with time. The task studied is a modification of Fitts' (1954) paradigm, with the difference that, as soon as the movement is started, the target size reduces at a constant rate until it finally vanishes. Very little research has been reported on this problem apart from Johnson and Hart (1987) and Hancock and Caird (1993). Two experiments are reported aimed at determining the parameters that affect the movement time and the probability of capturing a target when there are different amplitudes of movement, target widths and shrink rates. A multiplicative model is required to describe movement time data, which is dependent on Fitts' Index of Difficulty, the shrink rate and the product of these two variables. An alternative model describes the critical movement time, for a specified probability of target capture, in a modified form of Fitts' Law. Statement of Relevance: Modifications of Fitts' Law have been developed for many different movement tasks. Shrinking targets occur in circumstances such as gunnery and in computer games, where a target is moving away from the person. An expression is developed for the critical time to capture the target in terms of a modified form of Fitts' Law. 相似文献
97.
Decision trees are well-known and established models for classification and regression. In this paper, we focus on the estimation
and the minimization of the misclassification rate of decision tree classifiers. We apply Lidstone’s Law of Succession for
the estimation of the class probabilities and error rates. In our work, we take into account not only the expected values
of the error rate, which has been the norm in existing research, but also the corresponding reliability (measured by standard
deviations) of the error rate. Based on this estimation, we propose an efficient pruning algorithm, called k-norm pruning, that has a clear theoretical interpretation, is easily implemented, and does not require a validation set.
Our experiments show that our proposed pruning algorithm produces accurate trees quickly, and compares very favorably with
two other well-known pruning algorithms, CCP of CART and EBP of C4.5.
Editor: Hendrik Blockeel. 相似文献
98.
Mobile phone touchscreens have many ergonomic problems related to text entry. Previous studies, which attempted to use ambiguous keyboards to resolve problem of small keys, focused on the disambiguation process without consideration of the user loading on graphic user interface. This study investigates user loadings, which interfere with performance in the key selection phase when using an ambiguous keyboard. Hence, three QWERTY-like ambiguous keyboards and a standard QWERTY keyboard were compared via visual search and manual operation experiments. The visual search experiment shows that layouts with many letters per key were strongly related to long visual search times, and layouts with large keys were operated faster and more accurately in the manual operation experiment. Consequently, the trade-off between visual and manual loading differed among different letter-key assignments. This study is important in that it elucidates the impacts of visual and manual loadings on ambiguous keyboards, as well as in providing user interface designers with an enhanced understanding of how to design ambiguous keyboards based on user criteria.Relevance to industryAmbiguous keyboard designs in previous studies were generally far from the actual needs of users. This study examines the factors affecting text entry performance of users via the user-centered approach, improving the understanding of designers. 相似文献
99.
Sebastia Massanet 《Information Sciences》2011,181(11):2111-3916
A new class of fuzzy implications called the h-implications is introduced. They are implications generated from an additive generator of a representable uninorm in a similar way of Yager’s f- and g-implications which are generated from additive generators of continuous Archimedean t-norms and t-conorms. Basic properties of these implications are studied in detail. Modifications and generalizations of the initial definition are presented and their properties studied and compared between them. One of the modifications, called (h, e)-implications, is another example of a fuzzy implication satisfying the exchange principle but not the law of importation for any t-norm, in fact for any function F : [0, 1]2 → [0, 1]. 相似文献
100.
《Ergonomics》2012,55(10):1349-1356
AbstractA study was conducted in which 11 police officers wore one of three different types of Individual Light Armour Vests (ILAV), or normal station wear, for an entire day while completing power and agility-based tasks including a vertical jump (VJ), agility test, 20?m sprint and counter movement jump (CMJ). Despite all three ILAVs being significantly (p?<?.05) heavier than normal station wear, there were no significant differences between any of the ILAVs in VJ, time to complete the agility test, 20?m sprint time, peak force, velocity, power and jump distance in the CMJ. There was a significantly (p?<?.05) higher mean force produced in the CMJ while wearing all three ILAVs. The ILAV’s investigated do not appear to be heavy enough to significantly affect the power or agility of police officers. The utilisation of ILAVs by police officers does not appear to hinder policing tasks that involve agility or power development. Practitioner summary: The addition of the extra load of military-styled body armour is known to decrease performance and mobility. When compared to normal station wear, the wearing of three different ILAV types used in policing do not appear to be heavy enough to affect the power or agility of police officers. Abbreviations: ILAV: individual light armour vest; VJ: vertical jump; CMJ: counter movement jump; N: normal station wear 相似文献