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991.
Firms striving to maintain high rates of innovation need a continuous flow of new ideas. This is resulting in the establishment by large firms of IT platforms to generate ideas for innovation, and to encourage employees and customers to participate in innovation contests. However, there has been little published research on the use of IT platforms for idea generation by employees, and it is unclear whether they facilitate in‐house innovation. The purpose is to investigate how firms use IT platforms internally to generate ideas, and how their use contributes to the innovation process in large firms. We rely on data from two collaborative research projects in the automotive industry: Volvo Cars and Renault. We found that both firms used IT platforms as campaigns to promote innovation and to involve employees in the innovation process. The findings suggest that these virtual idea campaigns support innovation in large firms mainly by (1) encouraging employee creativity in idea generation and (2) involving employees and top managers simultaneously in the innovation process. This paper contributes to idea management systems theory by highlighting the importance of virtual idea campaigns for the firm's innovation process, and their dual role.  相似文献   
992.
A detector with high dynamic range designed for combined small- and wide-angle x-ray scattering experiments has been developed. It allows measurements on single events and reactive systems, such as particle formation in flames and evaporation of levitating drops. The detector consists of 26 channels covering a region from 0.5° to 60° and it provides continuous monitoring of the sampled signal without readout dead time. The time resolution for fast single events is about 40 μs and for substances undergoing slower dynamics, the time resolution is set to 0.1 or 1 s with hours of continuous sampling. The detector has been used to measure soot particle formation in a flame, burning magnesium and evaporation of a toluene drop in a levitator. The results show that the detector can be used for many different applications with good outcomes and large potential.  相似文献   
993.
Organizing for idea generation is a recurring challenge in intensive innovation contexts. The literature on ideation has reached a compelling consensus on the features that such organizational devices must possess to support sufficient creativity: learning processes and a creative climate of confidence to promote collaboration. However, current practical methodologies struggle to simultaneously realize these two features. In this paper, we explore the potential of Serious Games, a collaborative tool that has been used since the 1960s to facilitate learning processes through the simulation of reality and a role‐playing game, to induce an immersive experience and, more recently, to support the ideation process. To do so, we conducted an exploratory case study using a Serious Game to support ideation in a French medium‐sized business. We then assess the strengths and areas for improvement of this Serious Game with respect to an ideation performance framework based on the existing literature. Our findings show that Serious Games are efficient tools for supporting existing knowledge exchange between participants and collaboration by providing a creative climate, but they may not sufficiently support learning of the external knowledge required to attain high levels of originality. Accordingly, we discuss some crucial parameters to be further explored to allow for the effective managerial use of such methodologies, such as the fine‐tuning of the knowledge content that serves as a basis for the game.  相似文献   
994.
The human hand is a complex biological system able to perform numerous tasks with impressive accuracy and dexterity. Gestures furthermore play an important role in our daily interactions, and humans are particularly skilled at perceiving and interpreting detailed signals in communications. Creating believable hand motions for virtual characters is an important and challenging task. Many new methods have been proposed in the Computer Graphics community within the last years, and significant progress has been made towards creating convincing, detailed hand and finger motions. This state of the art report presents a review of the research in the area of hand and finger modeling and animation. Starting with the biological structure of the hand and its implications for how the hand moves, we discuss current methods in motion capturing hands, data‐driven and physics‐based algorithms to synthesize their motions, and techniques to make the appearance of the hand model surface more realistic. We then focus on areas in which detailed hand motions are crucial such as manipulation and communication. Our report concludes by describing emerging trends and applications for virtual hand animation.  相似文献   
995.
RÉSUMÉ

La numération a fait l'objet d'études importantes, notamment au Québec, durant les années 1980–2000. Les études ont révélé sa complexité ainsi que les difficultés que posent à la fois son enseignement et son apprentissage. La présente étude s'inscrit dans le prolongement d'une suite d'études didactiques sur ces difficultés. Plus précisément, elle investigue les connaissances d'élèves québécois de 3e année primaire sur la numération de position et les compare à celles d'une recherche phare menée par Bednarz et Dufour-Janvier dont les résultats ont fait l'objet de plusieurs publications (1982 Bednarz, N. et Dufour-Janvier, B. (1982). The understanding of numeration in primary school. Educational Studies in Mathematics, 13, 3357. [Google Scholar], 1984a Bednarz, N. et Dufour-Janvier, B. (1984a). La numération: les difficultés suscitées par son apprentissage ; une stratégie didactique cherchant à favoriser une meilleure compréhension. Grand N, 33, 531. [Google Scholar], 1984b Bednarz, N. et Dufour-Janvier, B. (1984b). La numération: une stratégie didactique cherchant à favoriser une meilleure compréhension. Grand N, 34, 117. [Google Scholar], 1988 Bednarz, N. et Dufour-Janvier, B. (1988). A constructivist approach to numeration in primary school: Results of a three year intervention with the same group of children. Educational Studies in Mathematics, 19, 299331. [Google Scholar]). Les résultats de notre étude montrent que si 30 ans ont passé depuis la recherche de Bednarz et Dufour-Janvier, peu de changements sont observés dans les conduites mathématiques des élèves en numération. Quelques hypothèses, relatives à la fois aux contraintes d'enseignement et aux difficultés spécifiques d'appropriation de la numération sont, au terme de l'article, formulées pour expliquer ces résultats.  相似文献   
996.
This paper addresses the problem of stability analysis for a given class of nonlinear systems resulting from the connection of a linear system with an isolated backlash operator. Constructive conditions based on LMIs to ensure closed-loop stability are proposed by using some suitable Lyapunov functionals with quadratic terms and Lure type terms, and generalized sector conditions. Additionally, the boundary of the associated set of all the admissible equilibrium points is precisely defined.  相似文献   
997.
We propose a framework of graph-based tools for the segmentation of microscopic cellular images. This framework is based on an object oriented analysis of imaging problems in pathology. Our graph tools rely on a general formulation of discrete functional regularization on weighted graphs of arbitrary topology. It leads to a set of useful tools which can be combined together to address various image segmentation problems in pathology. To provide fast image segmentation algorithms, we also propose an image simplification based on graphs as a pre processing step. The abilities of this set of image processing discrete tools are illustrated through automatic and interactive segmentation schemes for color cytological and histological images segmentation problems.  相似文献   
998.
In today's industrial context, competitiveness is closely associated to supply chain performance. Coordination between business units is essential to increase this performance, in order to produce and deliver products on time to customers, at a competitive price. While planning systems usually follow a single straightforward production planning process, this paper proposes that partners adapt together their local planning process (i.e. planning behaviours) to the different situations met in the supply chain environment. Because each partner can choose different behaviour and all behaviours will have an impact on the overall performance, it is difficult to know which is preferable for each partner to increase their performance. Using agent-based technology, simulation experiments have been undertaken to verify if multi-behaviour planning agents who can change planning behaviours to adapt to their environment can increase supply chain performance. These agents have been implemented in an agent-based planning platform, using a case study illustrating a lumber supply chain. The performance analysis shows that advanced planning systems can take advantage of using multiple planning processes, because of the dynamic context of supply chains.  相似文献   
999.
Social influence on song acquisition was studied in 3 groups of young European starlings raised under different social conditions but with the same auditory experience of adult song. Attentional focusing on preferred partners appears the most likely explanation for differences found in song acquisition in relation to experience, sex, and song categories. Thus, pair-isolated birds learned from each other and not from broadcast live songs, females did not learn from the adult male tutors, and sharing occurred more between socially associated peers. On the contrary, single-isolated birds clearly copied the adult songs that may have been the only source of attention stimulation. Therefore, social preference appears as both a motor for song learning and a potential obstacle for acquisition from nonpreferred partners, including adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Replica Management in the European DataGrid Project   总被引:1,自引:0,他引:1  
Within the European DataGrid project, Work Package 2 has designed and implemented a set of integrated replica management services for use by data intensive scientific applications. These services, based on the web services model, enable movement and replication of data at high speed from one geographical site to another, management of distributed replicated data, optimization of access to data, and the provision of a metadata management tool. In this paper we describe the architecture and implementation of these services and evaluate their performance under demanding Grid conditions.This work was partially funded by the European Commission program IST- 2000-25182 through the European DataGrid Project.  相似文献   
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