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101.
Joaquín M. Azagra-Caro Ignacio Fernández-de-Lucio François Perruchas Pauline Mattsson 《Scientometrics》2009,80(2):441-455
Most studies of patents citations focus on national or international contexts, especially contexts of high absorptive capacity,
and employ examiner citations. We argue that results can vary if we take the region as the context of analysis, especially
if it is a region with low absorptive capacity, and if we study applicant citations and examiner-inserted citations separately.
Using a sample from the Valencian Community (Spain), we conclude that (i) the use of examiner-inserted citations as a proxy
for applicant citations, (ii) the interpretation of non-patent references as indicators of science-industry links, and (iii)
the traditional results for geographical localization are not generalizable to all regions with low absorptive capacity. 相似文献
102.
Gaëtan Compère Jean‐François Remacle Johan Jansson Johan Hoffman 《International journal for numerical methods in engineering》2010,82(7):843-867
In this paper, we identify and propose solutions for several issues encountered when designing a mesh adaptation package, such as mesh‐to‐mesh projections and mesh database design, and we describe an algorithm to integrate a mesh adaptation procedure in a physics solver. The open‐source MAdLib package is presented as an example of such a mesh adaptation library. A new technique combining global node repositioning and mesh optimization in order to perform arbitrarily large deformations is also proposed. We then present several test cases to evaluate the performances of the proposed techniques and to show their applicability to fluid–structure interaction problems with arbitrarily large deformations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
103.
104.
Philippe Robin François Gitzhofer Pierre Fauchais Maher Boulos 《Journal of Thermal Spray Technology》2010,19(5):911-920
Ceramic functional coatings are frequently applied to structural materials, covering a wide range of thermomechanical and
electrochemical applications. The main limiting feature is their reliability when subjected to cyclic transient thermal stresses.
The study described in this article is a continuation of earlier research study focused on acoustic emission (AE) monitoring
of the thermomechanical aging effects in ceramic coatings. Here, emphasis is placed on the usefulness of combining AE short-term
monitoring with finite element modeling (FEM) to predict the performance of such coatings when subjected to cyclic thermal
loads. The FEM study presented in this article is based on a three-dimensional, time-dependent approach, of the stress fields
that developed within the coatings during the post-deposition cooling step and the thermal cycling. Experiments were conducted
using yttrium-stabilized zirconia (YSZ) and Alumina (Al2O3) ceramic coatings combined with a NiCr-based intermetallic bond coat. 相似文献
105.
106.
Massimiliano Tomasulo Erhan Deniz Tiziana Benelli Salvatore Sortino Françisco M. Raymo 《Advanced functional materials》2009,19(24):3956-3961
Two macromolecular constructs incorporating a single polymer backbone with multiple photochromic side chains are developed. Both systems are prepared from preformed photochromic [1,3]oxazines after the ring‐opening polymerization of their norbornene appendages. In solution, UV illumination of these polymers opens the [1,3]oxazine rings in their side chains in less than 6 ns and with a quantum yield of 0.09 in both instances. The photogenerated species incorporate a 4‐nitrophenolate chromophore, and hence, their formation is accompanied by the appearance of an intense band in the visible region of the absorption spectrum. The photoproducts revert spontaneously to the original state with first‐order kinetics in microseconds. Furthermore, both photochromic polymers tolerate hundreds of switching cycles with no sign of degradation, even in the presence of molecular oxygen. Thus, this design logic and choice of functional building blocks can translate into the realization of innovative photoresponsive materials with excellent photochromic performance. 相似文献
107.
Abdallah Hamze Dr. Anne Giraud Dr. Samir Messaoudi Dr. Olivier Provot Dr. Jean‐François Peyrat Prof. Jérôme Bignon Dr. Jian‐Miao Liu Dr. Joanna Wdzieczak‐Bakala Dr. Sylviane Thoret Joëlle Dubois Dr. Jean‐Daniel Brion Prof. Mouad Alami Dr. 《ChemMedChem》2009,4(11):1912-1924
The cytotoxic activities of 23 new isocombretastatin A derivatives with modifications on the B‐ring were investigated. Several compounds exhibited excellent antiproliferative activity at nanomolar concentrations against a panel of human cancer cell lines. Compounds isoFCA‐4 ( 2 e ), isoCA‐4 ( 2 k ) and isoNH2CA‐4 ( 2 s ) were the most cytotoxic, and strongly inhibited tubulin polymerization with IC50 values of 4, 2 and 1.5 μM , respectively. These derivatives were found to be 10‐fold more active than phenstatin and colchicine with respect to growth inhibition but displayed similar activities as tubulin polymerization inhibitors. In addition, cell cycle arrest in the G2/M phase and subsequent apoptosis was observed in three cancer cell lines when treated with these compounds. The disruptive effect of 2 e , 2 k and 2 s on the vessel‐like structures formed by human umbilical vein endothelial cells (HUVEC) suggest that these compounds may act as vascular disrupting agents. Both compounds 2 k and 2 s have the potential for further prodrug modification and development as vascular disrupting agents for treatment of solid tumors. 相似文献
108.
This article shows the results obtained when using secure spread-spectrum watermarking on gray-scale images in the watermark only attack (WOA) framework. Two secure modulations, natural watermarking (NW) and circular watermarking (CW), are compared with classical insecure modulations, spread spectrum (SS) and improved spread spectrum (ISS), from distortion, robustness, and security points of view. Implementations of CW and NW for still images are proposed: they use a wavelet transform and variable strength embedding with bounded distortion. Robustness of these schemes is assured by using JPEG compression and security is quantified by using a source separation technique: independent component analysis (ICA). Finally, tests are conducted on 2,000 natural images. They allow to distinguish between WOA security classes. 相似文献
109.
Clémentine Cornu Vincent Chapurlat Jean-Marc Quiot François Irigoin 《Annual Reviews in Control》2012,36(2):300-308
Increasing competition on markets induces a vital need for companies to improve their efficiency and reactivity. For this, a solution is to deploy, improve and manage their processes while paying a special attention on the abilities of the resources those involve. Particularly, their interoperability is considered in this article as a challenge conditioning the success of the deployment. Consequently, this paper provides a comparison of existing interoperability assessment solutions and presents a methodology to assess interoperability of people, material resources and organisation units involved or that could be involved in a process, all along the deployment effort. This methodology is usable for prevention, detection and correction of interoperability problems. 相似文献
110.
Quentin Lequy Mathieu Bouchard Guy Desaulniers Fran?ois Soumis Beyime Tachefine 《Journal of Scheduling》2012,15(2):239-251
In some companies such as large retail stores, the employees perform different activities (e.g., cashier or clerk in a specific
department) to respond to a customer demand for each activity that varies over the planning horizon and must be fulfilled
as soon as possible. For a given time period, this demand translates into an ideal number of employees required for the corresponding
activity. During a work shift, an employee can be assigned to several activities that are interruptible at any time and subject
to operational constraints (required skills, minimum and maximum assignment durations). Given work shifts already assigned
to the employees, the multi-activity assignment problem (MAAP) consists of assigning activities to the shifts such that the
activity demands are satisfied as best as possible over the planning horizon. In this paper, we propose three integer programming
models for the MAAP and develop various heuristics based on mathematical programming techniques. Computational results obtained
on randomly generated MAAP instances show that a heuristic column generation method embedded into a rolling horizon procedure
provides the best results in general. 相似文献