Hybrid R&D

We develop a model of R&D competition and collaborationin which individual firms carry out independent in-house researchand also undertake joint research projects with other firms. Weexamine the impact of collaboration on in-house research andexplore the circumstances under which a hybrid organization ofR&D which combines the two is optimal for firms andsociety. We find that investments in independent research and injoint research are complementary: an increase in the number ofjoint projects also increases in-house research. Firm profits arehighest under a hybrid organization if the number of firms issmall (less than 5) while they are highest with pure in-houseresearch if the number of firms is large (5 or more). However,social welfare is maximized under a hybrid organization of R&D inall cases. Our analysis also yields new results on the role ofcooperative R&D. We find that non-cooperative decision making byfirms leads to larger R&D investments and higher social welfarethan fully cooperative decision making. However, a hybrid form ofdecision making where there is bilateral cooperation in jointprojects and non-cooperative decision making in in-house researchyields the highest level of welfare in concentrated industries.

Viscosity and tribology of copper oxide nanofluids

Nanofluids, a term proposed by Choi in 1995 [1], are composites consisting of solid nanoparticles with sizes varying generally from 1 to 100 nm dispersed in a liquid. Numerous nanoparticles used as oil additives have been investigated in recent years [2-7]. Results show that they deposit on the rubbing surface and improve the tribological properties of the base oil, displaying good friction and wear reduction characteristics even at concentrations below 2%wt. Although the viscosity of the nanofluids is a property of crucial importance for film forming, and hence friction and wear reduction, which are characteristic of lubricants, only Hwang et al. [8] have studied thermal characteristics, kinematic viscosity and tribological properties of nanofluids simultaneously. In this paper, we present measurements of dynamic viscosity of nanofluids formed by copper oxide nanoparticles dispersed in a polyalphaolefin, for temperatures and concentrations varying from 20 to 60ºC and 0.5 to 2% wt., respectively. Dependence of the nanofluid viscosity to the solid fraction and temperature was compared with existing models and its influence on lubrication was also analysed

STI–DUI learning modes, firm–university collaboration and innovation

In this study, the relationship between the formation of different types of collaborative agreements and firm innovation is examined. Two types of agreements are distinguished: ‘‘science and technology-based’’ (STI) and ‘‘learning-by-doing, by-using and byinteracting-based’’ (DUI) partnerships. A fixed-effects logit estimation is applied on an extensive panel of Spanish manufacturing and service firms to analyze the separate and combined impact of collaborative agreements associated to STI and/or DUI modes of learning, paying special attention to the role of partnerships with universities. While STI and DUI partnerships are important for product and process innovation in both separate and combined ways, the results demonstrate that different types of collaboration lead to different types of innovation. Product innovation benefits more from the combination of DUI and STI partnerships and process innovation seems to be more closely linked to DUI-related partnerships undertaken by firms. Findings also show that firm–university collaboration, without the engagement of other STI and DUI agents in the partnership, seems to be weak for product innovation

R&D Networks

Many markets are characterized by a high level of inter-firm collaboration in R&D activity. This paper develops a simple model of strategic networks which captures two distinctive features of such collaboration activity: bilateral agreements and non-exclusive relationships. We study the effects of collaborations on individual R&D effort, cost reduction, and market performance. We then examine the incentives of firms to form collaborative links and the architecture of strategically stable networks. Our analysis highlights the interaction between market competition and R&D network structure. We find that if firms are Cournot competitors then individual R&D effort is declining in the level of collaborative activity. However, cost reduction and social welfare are maximized under an intermediate level of collaboration. In some cases, firms can gain market power, and even induce exit of rival firms, by forming suitable collaboration agreements. Moreover, under certain circumstances, such asymmetric collaboration networks are also strategically stable. By contrast, if firms operate in independent markets then individual R&D effort is increasing in the level of collaborative activity. Cost reduction and social welfare are maximized under the complete network, which is also strategically stable.strategic alliances;networks;research and development

El control del tratamiento superficial de los tapones de corcho

Es bien sabido que el corcho como material posee una serie de características que le hacen susceptible de múltiples aplicaciones industriales (ligereza, elasticidad, compresibilidad, impermeabilidad, elevado rozamiento, aislante térmico etc.) de las cuales la más importante es la fabricación de tapones para el embotellado de los mejores caldos. Esto no solamente se debe al punto de vista económico (por el valor añadido que aporta), sino a lo que representa culturalmente en el mundo del vino. Un buen comportamiento de los tapones en el proceso de encorchado, así como de su permanencia en botella hasta el destapado, está íntimamente ligado a una serie de características de naturaleza físico-mecánica inherentes al corcho, al riguroso y cuidado proceso de fabricación y, de forma muy importante, a los tratamientos superficiale

Can it be measured - Fracture Toughness from Repetitive Nano-impacts Test?

The design of coatings in the field of engineering applications aims at a progressive shift to the development of “hard but tough” coatings. The difficulty in assessing their mechanical behaviour by conventional methods is behind the growing relevance of “in situ” experiments using instrumented microindentation technique. This technique is one of the few able to investigate the mechanical properties along of whatever length range, i.e. from small volume to bulk material. Information from the load-depth curve of indentation has proven to be abundant and varied and it can be used to determine several mechanical properties such as: hardness, Young’s modulus, yield strength, viscoelastic properties, etc [[1]].In fact, from this technique the evaluation of wear-resistance by hardness and/or scratch testing have become in a routine in a multitude of different materials [[2]]. Nevertheless, the results are not always accurate, particularly when the surfaces are subjected to erosive wear during service and fail by a fatigue process. For the purpose of providing a solution, impact technique have been developed to extend the capability of depth-sensing indentation/scratch instrumentation to perform fatigue testing in a wide variety of surfaces, such as DLC and amorphous carbon [[3]], plasma electrolytic oxidation surface[[4]], polymers [[5]] and numerous coatings for cutting tools [[6]]. Along the experiment, this technique produces a repetitive impact with a high stresses and high strain rates, simulating the fatigue conditions under repetitive contact conditions, at the nano or micro-scale. Depending on the material ductility and the load magnitude, fracture of the surface may be achieved. Therefore, the question is whether from these tests it is possible to calculate fracture toughness values, KC, since conventional ways to determine fracture toughness by single edge notched beam (SENB), chevron notched beam (CVNB) and double cantilever beam (DCB) are not applicable for systems whose dimensions are between a few hundreds of nanometers to a few microns. Along this work, it will be studied the feasibility of using impact tests with a cube-corner tip using low loads, assuming that the indented coatings resembles the pattern for the fracture mode type I considered in the classical fracture toughness tests. For this purpose, fracture toughness calculation by impact test will be analysed first in a brittle bulk Al2O3 material, since its mechanical properties are well known. After this, fracture toughness of Al2O3 coating on ductile metallic substrate will be analysed for chequing the substrate contribution and the applicability of the classical indentation models, IM, in case of impact done at low loads. Finally, a novel method to determine the fracture toughness in metallic nanomultillayer coatings by impact test will be show. The design of coatings in the field of engineering applications aims at a progressive shift to the development of “hard but tough” coatings. The difficulty in assessing their mechanical behaviour by conventional methods is behind the growing relevance of “in situ” experiments using instrumented microindentation technique. This technique is one of the few able to investigate the mechanical properties along of whatever length range, i.e. from small volume to bulk material. Information from the load-depth curve of indentation has proven to be abundant and varied and it can be used to determine several mechanical properties such as: hardness, Young’s modulus, yield strength, viscoelastic properties, etc [[1]].In fact, from this technique the evaluation of wear-resistance by hardness and/or scratch testing have become in a routine in a multitude of different materials [[2]]. Nevertheless, the results are not always accurate, particularly when the surfaces are subjected to erosive wear during service and fail by a fatigue process. For the purpose of providing a solution, impact technique have been developed to extend the capability of depth-sensing indentation/scratch instrumentation to perform fatigue testing in a wide variety of surfaces, such as DLC and amorphous carbon [[3]], plasma electrolytic oxidation surface[[4]], polymers [[5]] and numerous coatings for cutting tools [[6]]. Along the experiment, this technique produces a repetitive impact with a high stresses and high strain rates, simulating the fatigue conditions under repetitive contact conditions, at the nano or micro-scale. Depending on the material ductility and the load magnitude, fracture of the surface may be achieved. Therefore, the question is whether from these tests it is possible to calculate fracture toughness values, KC, since conventional ways to determine fracture toughness by single edge notched beam (SENB), chevron notched beam (CVNB) and double cantilever beam (DCB) are not applicable for systems whose dimensions are between a few hundreds of nanometers to a few microns. Along this work, it will be studied the feasibility of using impact tests with a cube-corner tip using low loads, assuming that the indented coatings resembles the pattern for the fracture mode type I considered in the classical fracture toughness tests. For this purpose, fracture toughness calculation by impact test will be analysed first in a brittle bulk Al2O3 material, since its mechanical properties are well known. After this, fracture toughness of Al2O3 coating on ductile metallic substrate will be analysed for chequing the substrate contribution and the applicability of the classical indentation models, IM, in case of impact done at low loads. Finally, a novel method to determine the fracture toughness in metallic nanomultillayer coatings by impact test will be show. [1] W. C. Oliver, G. M. Pharr. J. Mater. Res. 1992;7:1564. [2] J.L. Meneve, J.F. Smith, N.M. Jennett, S.R. Saunders. Appl. Surf. Sci. 1996;100/101:64 [3]B. Beake. Surf. Coat. Technol. 2005:198:90 [4]J.M. Wheeler, C.A. Collier, J.M. Paillard, J.A. Curran. Surf. Coat. Technol. 2010;204:3399. [5]B. Beake, S. Goodes, J. Smith, F. Gao. J. Mater. Res. 2004;19:237. [6]B.D. Beake, V.M. Vishnyakov, J.S. Colligon. J. Phys. D Appl. Phys. 2011;4

Internetmarkten: wie profiteert?

Economen lijken het er over eens dat het internet positieve welvaartseffecten kan hebben. Maar of het werkelijk de mogelijkheden biedt om tot een perfecte markt te komen, blijft de vraag. Werpt het internet geen nieuwe barrières op? En aan wie valt de extra welvaart toe? Over visionairs en technocraten

Two Firms is enough for Competition, but Three or More is better

We present an oligopoly model where a certain fraction of consumers engage in costly non-sequential search to discover prices. There are three distinct price dispersed equilibria characterized by low, moderate and high search intensity, respectively. We show that the effects of an increase in the number of firms active in the market are sensitive (i) to the equilibrium consumers' search intensity, and (ii) to the status quo number of firms. For instance, when consumers search with low intensity, increased competition does not affect expected price, leads to greater price dispersion and welfare declines. In contrast when consumers search with high intensity, increased competition results in lower prices when the number of competitors in the market is low to begin with, but in higher prices when the number of competitors is large. Moreover, duopoly yields identical expected price and price dispersion but higher welfare than an infinite number of firms