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31.
Emmanuel Bruno Nicolas Faessel Herv�� Glotin Jacques Le Maitre Michel Scholl 《World Wide Web》2011,14(5-6):623-649
We present in this paper a model for indexing and querying web pages, based on the hierarchical decomposition of pages into blocks. Splitting up a page into blocks has several advantages in terms of page design, indexing and querying such as (i) blocks of a page most similar to a query may be returned instead of the page as a whole (ii) the importance of a block can be taken into account, as well as (iii) the permeability of the blocks to neighbor blocks: a block b is said to be permeable to a block b?? in the same page if b?? content (text, image, etc.) can be (partially) inherited by b upon indexing. An engine implementing this model is described including: the transformation of web pages into blocks hierarchies, the definition of a dedicated language to express indexing rules and the storage of indexed blocks into an XML repository. The model is assessed on a dataset of electronic news, and a dataset drawn from web pages of the ImagEval campaign where it improves by 16% the mean average precision of the baseline. 相似文献
32.
33.
Hans-Henrik Hvolby Author Vitae Jacques H. Trienekens Author Vitae 《Computers in Industry》2010,61(9):808-812
Four main frameworks for intercompany relationships (SCOR, CPFR, ISA95 and OAG) are discussed and compared. The link between the frameworks and different supply chain integration applications such as ERP, CRM and VMI are pictured. Finally the state-of-the-art, future state and challenges of the supply chain integration applications are discussed. It is concluded that the main challenge with respect to frameworks supporting business systems integration is to extend them with implementation functionality to better support business system application development. An example of this is customer requirement fulfillment processes such as product development and order fulfillment. Not only do they cross the borders of the company's departments (sales, logistics, purchasing, etc) but also various companies in the supply chain. In spite of this development, business integration across systems and borders are still not matured and to a large extend based on human interaction. 相似文献
34.
This paper shows how to apply discrete time non-homogeneous semi-Markov processes (DTNHSMP) with an age index to credit risk.
The idea is to consider the credit risk problem as a reliability model indexed by the age and in this way, many semi-Markov
results could be adapted to describe credit risk problem. The default state is seen as a “non working state”. As the semi-Markov
process is a generalization of Markov process, the presented model can be seen as a more general migration model. In fact,
in semi-Markov environment the distribution function (d.f.) of the waiting time before a transition can be of any type and
without the strong constraints of the Markov model. Furthermore, some results on the asymptotic behavior of the presented
model are given. This permits the construction of the d.f. of the default random variable for each “working state”. An example,
constructed manipulating some Standard & Poor’s (S&P) data, is presented. 相似文献
35.
QUAD: A multivariate stream cipher with provable security 总被引:1,自引:0,他引:1
36.
Samuel Aupetit Virginie Gallier Jacques Riff Stéphane Espié Flavien Delgehier 《Ergonomics》2016,59(8):1109-1120
This article sets out to identify the typical risky situations experienced by novice motorcyclists in the real world just after licensing. The procedure consists of a follow-up of six novices during their first two months of riding with their own motorbike instrumented with cameras. The novices completed logbooks on a daily basis in order to identify the risky situations they encountered, and were given face-to-face interviews to identify the context and their shortcomings during the reported events. Data show a large number of road configurations considered as risky by the riders (248 occurrences), especially during the first two weeks. The results revealed that a lack of hazard perception skills contributed to the majority of these incidents. These situations were grouped together to form clusters of typical incident scenarios on the basis of their similarities. The most frequent scenario corresponds to a lane change in dense traffic (15% of all incidents). The discussion shows how this has enhanced our understanding of novice riders’ behaviour and how the findings can improve training and licensing. Lastly, the main methodological limitations of the study and some guidelines for improving future naturalistic riding studies are presented.
Practitioner Summary:
This article aims to identify the risky situations of novice motorcyclists in real roads. Two hundred forty-eight events were recorded and 13 incident scenarios identified. Results revealed that a lack of hazard perception contributed to the majority of these events. The most frequent scenario corresponds to a lane change in dense traffic. 相似文献
37.
Hendriks Martijn Verriet Jacques Basten Twan Theelen Bart Brassé Marco Somers Lou 《International Journal on Software Tools for Technology Transfer (STTT)》2017,19(4):487-510
International Journal on Software Tools for Technology Transfer - System designers make trade-offs between metrics of interest such as execution time, functional quality and cost to create a... 相似文献
38.
Transfer of learning in virtual environments: a new challenge? 总被引:1,自引:0,他引:1
The aim of all education is to apply what we learn in different contexts and to recognise and extend this learning to new
situations. Virtual learning environments can be used to build skills. Recent research in cognitive psychology and education
has shown that acquisitions are linked to the initial context. This provides a challenge for virtual reality in education
or training. A brief overview of transfer issues highlights five main ideas: (1) the type of transfer enables the virtual
environment (VE) to be classified according to what is learned; (2) the transfer process can create conditions within the
VE to facilitate transfer of learning; (3) specific features of VR must match and comply with transfer of learning; (4) transfer
can be used to assess a VE’s effectiveness; and (5) future research on transfer of learning must examine the singular context
of learning. This paper discusses how new perspectives in cognitive psychology influence and promote transfer of learning
through the use of VEs. 相似文献
39.
Quality control lead times are one of most significant causes of loss of time in the pharmaceutical and cosmetics industries. This is partly due to the organization of laboratories that feature parallel multipurpose machines for chromatographic analyses. The testing process requires long setup times and operators are needed to launch the process. The various controls are non-preemptive and are characterized by a release date, a due date and available routings. These quality processes lead to significant delays, and we therefore evaluate the total tardiness criterion. Previous heuristics were defined for the total tardiness criterion, parallel machines, and setup such as apparent tardiness cost (ATC) and ATC with setups (ATCS). We propose new rules and a simulated annealing procedure in order to minimize total tardiness. 相似文献
40.
Pure and rare earth doped gadolinium oxide (Gd2O3) waveguide films were prepared by a simple sol-gel process and dip-coating method. Structure of Gd2O3 films annealed at different temperature was investigated by X-ray diffraction and transmission electron microscopy. Oriented growth of (400) face of Gd2O3 has been observed when the films were deposited on amorphous substrate. The refractive index and thickness of films were determined by m-lines spectroscopy. The laser beam (λ= 632.8 nm) was coupled into the film by a prism coupler and the propagation length is about 3.5 cm. Luminescence properties of europium ions doped films were measured by waveguide fluorescence spectroscopy, which shows disordered environment for Eu^3 at 400℃. 相似文献