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In this paper we examine how foreign actors capitalize on their ethnic identity to gain skills and capabilities that enable them to operate in a new and strange environment. We explore the mechanisms by which Bulgarian entrepreneurs in London use their ethnic identity to develop competitive advantage and business contacts. We find that the entrepreneurs studied gain access to a diaspora network, which enables them to develop essential business capabilities and integrate knowledge from both home and host country environments. The diaspora community possesses a collective asset (transactive memory) that allows its members to remove competition from the interfirm level to the network level (i.e., diaspora networks vs. networks of native businesspeople). Additionally, the cultural identity and networks to which community members have access provide bridging capabilities that allow diaspora businesspeople to make links to host country business partners and thus embed themselves in the host country environment. Thus, this paper adds to the growing body of work showing how foreignness can serve as an asset in addition to its better-known role as a liability.  相似文献   
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An overlapping composite track coating was produced on a steel surface by preplacing a 0·5 mm thick layer of TiC powder and then melting using a tungsten inert gas torch of constant energy input. The influence of the overlapping operation on preheating of the substrate, the dissolution of TiC particulates and the subsequent depth and hardness of the composite layer was analysed. The melt microstructure consisted of both undissolved and partially dissolved TiC particulates, together with a variety of morphologies and sizes of TiC particles precipitated during solidification. Preheating, resulting from the overlapping operation, occurred, producing additional melting of the TiC particulates and deeper melt depths but with a reduced volume fraction of TiC precipitates in the subsequent tracks. A maximum hardness of over 800 HV was developed in the composite layer. The high hardness was unevenly distributed in tracks melted at the initial and final stages, while it varied across the melt depths in other tracks.  相似文献   
4.
As one of the representative unsupervised data augmentation methods, generative adversarial networks (GANs) have the potential to solve the problem of insufficient samples in fault diagnosis of rotating machinery. However, the existing unsupervised GANs are usually incapable of simultaneously generating multi-mode fault samples and have some shortcomings such as mode collapse and gradient vanishing. To overcome these deficiencies, a supervised model called modified auxiliary classifier GAN (MACGAN) designed with new framework is proposed in this paper. Firstly, a new ACGAN framework is developed by adding an independent classifier to improve the compatibility between the classification and discrimination. Secondly, the Wasserstein distance is introduced in the new loss functions to overcome mode collapse and gradient vanishing. Finally, to achieve stable training, a spectral normalization is used to replace the weight clipping to constrain the weight parameters of discriminator. The proposed method is applied to fault diagnosis of bearing and gear. Compared with the existing GANs, the proposed method can more efficiently generate multi-mode fault samples with higher qualities, which can be used to assist the training of deep learning-based fault diagnosis models with high accuracy and good stability.  相似文献   
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Carbon deposition occurs when Dimethyl ether (DME) fuel is used for SOFC, leading to battery degradation. In order to study the effect of water addition on carbon deposition, this work used reactive force field molecular dynamics (Reaxff MD) to simulate the process of carbon deposition with or without water addition, and analyze its anti-carbon deposition mechanism on nickel-based anode.It is found that the number of carbon atoms on nickel can be effectively reduced by mixing water with fuel. As the H2O/DME ratio increases, there are fewer carbon atoms on the nickel anode. And there are two main ways for water molecules to resist carbon deposition. First is that the OH group generated by decomposition of water molecules at high temperature reacts with CH component to form aldehyde group, which reduces the formation of carbon deposition precursor. The other is that the increase of water molecules introduces more oxygen atoms into the system, and the carbon atoms formed by DME molecules combine with oxygen atoms to form CO, thus reducing carbon deposition. This study is helpful to promote the industrialization of DME as SOFC fuel.  相似文献   
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The shortage of land together with heavy industrialization in Japan makes incineration, and its associated process of sludge melting, favoured methods for the disposal of sewage sludge. The technology used in Japan for thermal drying of sludge and sludge incineration is similar to that used in other industrialized countries. The sludge melting processes which are used in a few installations are unusual. Most of the ash or slag which is produced from the burning of sewage sludge is disposed of by landfill, although an increasing amount of ash and slag is being disposed of by incorporation into construction materials.  相似文献   
9.
T his STUDY INVESTIGATES the decline in pH of soft waters during distribution. The fieldwork and laboratory data confirmed and quantified the pH decline in soft water that had had the pH increased by lime addition at the treatment stage. A pH of 9.0 can decline to 7.5 during distribution. The role of humic acid as a causative agent of pH decline is examined in detail by modified jar test experiments and the development of a dialysis technique. The results of these experiments show that binding or complexing occurs between the humic acid and the calcium ions. This complexing generates H+ ions with the consequential decline in pH of the water.  相似文献   
10.
Book reviews     
Managing Cities. The New Urban Context. P. Healey, S. Cameron, S. Davoudi, S. Graham & A. Madani‐Pour (Eds) Chichester, John Wiley and Sons, 1995, £14.95 pb, ISBN 0–471–95533–7

Industrial Property: Policy and Economic Development. Rick Ball & Andy Pratt (Eds). London, Routledge, 1994, £45.00 hb, ISBN 0–415–09152–7

Grassroots Environmental Action: People's Participation in Sustainable Development. Dharam P. Ghai & Jessica M. Vivian (Eds). London and New York, Routledge, 1995 (pb), 347 pp., ISBN 0–415–12703–3

Services and Space: Key Aspects of Urban and Regional Development. N. Marshall & P. Wood. Essex, Longman Scientific and Technical, 1995, 294 pp., £17.99 pb, ISBN 0–582–25162–1

Servicing The Middle Classes: Class, Gender and Waged Domestic Labour in Contemporary Britain. Nicky Gregson & Michelle Lowe. Routledge, 1994, vii + 327 pp., £13.99 pb, ISBN 0–419–08531–4

Urban Development Planning: Lessons for the Economic Reconstruction of South Africa's Cities. Richard Tomlinson. Johannesburg, Witwatersrand University Press, 1994, 277 pp., £14.95 pb, ISBN 1–868–14258–2  相似文献   

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