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121.
The objective of the paper is to identify some of the determinants of foreign investment of the largest multinational enterprises (MNEs) operating in the wine industry. The factors that drive firms to invest abroad and those that determine the location of those investments are examined in the case of the world wine industry. The list of the largest MNEs has been compiled using financial databases and company websites. Spearman rank correlation values are calculated between the ranking of the location popularity of host countries and the ranking of the independent variables or indices for the same period. The results of this study have some important implications. They indicate that location-specific advantages of host countries do provide an explication of the internationalization of firms in some preferred countries rather than others. 相似文献
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124.
Denis Cavallucci François Rousselot Cecilia Zanni 《Creativity & Innovation Management》2009,18(2):71-80
Tools and methods developed during the era of quality and optimization have shown their limitations and become inappropriate in the context of the requirements of innovation. Nowadays the need to rebuild design practices in enterprises is strongly felt both in terms of human skills and methodological expertise. In part, a way to face the innovation era's difficulties has been provided through the theory of inventive problem solving. This theory represents a significant breakthrough in driving problem statement and solving in a direction that is expressed through the idea that technical systems are driven by objective laws. A second postulate concerns the notion of contradiction, but so far only few contributions have addressed the relations between laws and contradictions. This paper, through a qualitative approach, presents a solution to this limitation and proposes a possible use of laws within the choice of the appropriate conflicting pair, prior to the use of any TRIZ solving techniques. Tests to observe the impact of the proposed approach were conducted in a French engineering ‘grande école’ during three semesters with 180 engineers. The contribution of this paper is twofold. On the one hand, there is a theoretical contribution to the theory of inventive problem solving. In addition, the proposed method offers especially TRIZ practitioners new ways for problem understanding and problem formulation. 相似文献
125.
Réfrégier P Goudail F 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(6):1223-1233
Many applications use an active coherent illumination and analyze the variation of the polarization state of optical signals. However, as a result of the use of coherent light, these signals are generally strongly perturbed with speckle noise. This is the case, for example, for active polarimetric imaging systems that are useful for enhancing contrast between different elements in a scene. We propose a rigorous definition of the minimal set of parameters that characterize the difference between two coherent and partially polarized states. Indeed, two states of partially polarized light are a priori defined by eight parameters, for example, their two Stokes vectors. We demonstrate that the processing performance for such signal processing tasks as detection, localization, or segmentation of spatial or temporal polarization variations is uniquely determined by two scalar functions of these eight parameters. These two scalar functions are the invariant parameters that define the polarimetric contrast between two polarized states of coherent light. Different polarization configurations with the same invariant contrast parameters will necessarily lead to the same performance for a given task, which is a desirable quality for a rigorous contrast measure. The definition of these polarimetric contrast parameters simplifies the analysis and the specification of processing techniques for coherent polarimetric signals. 相似文献
126.
The calculated spectral transmittance of a multilayer laser mirror is used to determine the effective index of the single layer equivalent to the multilayer stack. We measure the artificial anisotropy of photoresist thin films whose structure is a one-dimensional, subwavelength grating obtained from interference fringes. The limitation of the theory of the first-order effective index homogenization is discussed. We designed normal-incidence, polarizing coating and a polarization rotator by embedding anisotropic films in simple multilayer structures. 相似文献
127.
Monfette Marie-Eve; Grimard Fran?ois; Ivers Hans; Blais Marie-Claude; Lavoie Vicky; Boisvert Jean-Marie 《Canadian Metallurgical Quarterly》2006,38(3):261
The popularity of the Fear of Negative Evaluation scale (FNE; Watson & Friend, 1969) stems from the centrality of this construct in personality, social and clinical psychology. In order to meet the needs of the Francophone researchers community, Kéroack, Boisvert, and Prévost (1987) traduced the short version of this instrument. Since social anxiety is most salient in adolescence, there is a need for normative and psychometric data for this population. This research aims at documenting the psychometric properties and norms for Francophone adolescents. Five hundred and seventy-eight participants aged from 14 to 19 years completed the French versions of the short FNE and the Social Avoidance and Distress scale. The factorial structure, the internal consistency and the convergent validity analyses confirm the traduction's quality and the questionnaire's validity. Norms are presented separately for females and males. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
Jochen Alber Hongbing Fan Henning Fernau Rolf Niedermeier Fran Rosamond 《Journal of Computer and System Sciences》2005,71(4):385-405
We establish a refined search tree technique for the parameterized DOMINATING SET problem on planar graphs. Here, we are given an undirected graph and we ask for a set of at most k vertices such that every other vertex has at least one neighbor in this set. We describe algorithms with running times O(8kn) and O(8kk+n3), where n is the number of vertices in the graph, based on bounded search trees. We describe a set of polynomial time data-reduction rules for a more general “annotated” problem on black/white graphs that asks for a set of k vertices (black or white) that dominate all the black vertices. An intricate argument based on the Euler formula then establishes an efficient branching strategy for reduced inputs to this problem. In addition, we give a family examples showing that the bound of the branching theorem is optimal with respect to our reduction rules. Our final search tree algorithm is easy to implement; its analysis, however, is involved. 相似文献
129.
Hans Korving Fran?ois H. L. R. Clemens Jan M. van Noortwijk 《Canadian Metallurgical Quarterly》2006,132(10):1076-1085
Sewage pumping stations represent an element of the sewer system, which is directly responsible for affecting serviceability; i.e., failing pumps may result in combined sewer overflows or flooding. However, failures of sewage pumps are not yet incorporated in sewer assessments due to lack of data. This paper presents the analysis of pump failure data provided by two sewer management authorities in The Netherlands. Pump failures have been studied accounting for the nature of the failures, the operation and maintenance procedures of the management authority, the aging of the pumps, and the changes in the environment of pumps. The analysis shows that sewage pumps fail relatively often due to the composition of sewage and the discontinuous operation of the pumps. The interarrival time and the duration of failures are highly variable and independent of the specific function of the pump. Resulting pump failure characteristics are applied in a Monte Carlo simulation to calculate the impact of failures on combined sewer overflow volumes. The results indicate that the serviceability of sewer systems is significantly affected by failing pumps. Therefore, including pump availability in sewer system assessments should be considered. 相似文献
130.
Sylvain Paris François X. Sillion Long Quan 《International Journal of Computer Vision》2006,66(2):141-161
Surface reconstruction from multiple calibrated images has been mainly approached using local methods, either as a continuous
optimization problem driven by level sets, or by discrete volumetric methods such as space carving. We propose a direct surface
reconstruction approach which starts from a continuous geometric functional that is minimized up to a discretization by a
global graph-cut algorithm operating on a 3D embedded graph. The method is related to the stereo disparity computation based
on graph-cut formulation, but fundamentally different in two aspects. First, existing stereo disparity methods are only interested
in obtaining layers of constant disparity, while we focus on high resolution surface geometry. Second, most of the existing
graph-cut algorithms only reach approximate solutions, while we guarantee a global minimum. The whole procedure is consistently
incorporated into a voxel representation that handles both occlusions and discontinuities. We demonstrate our algorithm on
real sequences, yielding remarkably detailed surface geometry up to 1/10th of a pixel.
Author has worked on this project during his Ph. D. at ARTIS 相似文献