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91.
Supply chain networks need to respond efficiently to operation disruptions, as one of their aims is to guarantee the on time delivery of products. Hence, robustness has become one of the important issues to consider when designing supply networks. There are alternative ways to measure what robustness means in this context. In this paper, we propose a new metric based on the effect on service level of the collapse of active transportation links. Numerical experiments are carried out to understand how different design factors affect robustness. Robustness under a targeted attack is compared with robustness to random failures. Results show that flow complexity (i.e. the number of potential transportation links between supply network nodes) is the most influential factor affecting supply network and its robustness, as well as the service level that can be maintained after disruptions. Thus, diversification both in supply sources and transportation routes seems to be key to robustness. 相似文献
92.
Ana Fernndez Vilas Rebeca P. Díaz Redondo Manuel Ramos Cabrer Jos J. Pazos Arias Alberto Gil Solla Jorge García Duque Martín Lpez Nores Yolanda Blanco Fernndez 《Software》2006,36(13):1421-1442
Nowadays, we are living in a time of important technological changes that affect our lives at home and our communication with the outside world. Among them, the developments in Interactive Digital TV (IDTV) and the smart home field can be considered as particularly important. Related to the former, the new Set‐Top Boxes (STBs) are not only a decoder for digital television broadcast but also an entry point to the Information Society and a suitable platform to support the execution of interactive applications. With regards to the latter, the Residential Gateways (RGs) combine different network technologies to allow the connection of different electronics devices and appliances at home, not only with each other but also with the Internet. Since there is no widespread consensus about the configurations and functions of the RGs, we propose to coordinate the two aforementioned worlds by extending the functionality of STBs to become a RG. Our proposal consists of merging the Multimedia Home Platform (MHP), one of the main standard frameworks for IDTV, with Open Service Gateway Initiative (OSGi), the most widely used open platform to set up RGs. To overcome the radically different nature of these specifications—the function‐oriented MHP middleware and the service‐oriented OSGi framework—we define a new kind of application, coined as XbundLET. This application is able to bridge the gap between the two frameworks and make their interaction feasible. We also show how this proposal has the potential to enable the production of scenarios that cannot currently be put into practice in a natural way. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
93.
Study of the binding in an aqueous medium of inclusion complexes of several cyclodextrins involving fenoprofen calcium 总被引:1,自引:0,他引:1
Díaz D Escobar Llanos CM Bernad Bernad MJ 《Drug development and industrial pharmacy》1999,25(1):107-110
Interactions among fenoprofen calcium and alpha-, beta-, gamma- and hydroxypropyl-beta-cyclodextrins (HP-beta-CD) were evaluated in aqueous solution by UV/vis and fluorescence direct spectroscopies and monodimensional (1D) 1H-NMR. Different UV/vis and fluorescence emission spectra were obtained to study the apparent binding constants (K) to define the most appropriate cyclodextrin to form the inclusion complexes (IC). beta-CD and HP-beta-CD clearly fit the magnitude of stability constant data of the complexes to take into account the pharmaceutical technology interest. 相似文献
94.
The corrosion inhibition effect of the following organic additives: 2‐butin‐1,4‐diol (BD), N,N′‐dimethylthiourea (DMTU), N,N′‐diethylthiourea (DETU) and N,N′‐diisopropylthiourea (DITU), in steel pickling baths (sulphuric acid solutions) was studied by means of weight loss and electrochemical measurements like open circuit potential (OCP), polarization curves and impedance spectroscopy (EIS). A significant decrease in the corrosion rate was observed in presence of the investigated compounds depending on the nature and the concentration of the additives. The weight loss experiments show an inhibitory efficiency that reaches values beyond 98 %. The protective effect increases with the enlargement of the lateral chain size in the case of the thioureas. The electrochemical experiments show also a protective effect of the organic additives against corrosion. Their adsorptive behaviour is found to follow the Langmuir model. 相似文献
95.
M. Epifani R. Díaz J. Arbiol E. Comini N. Sergent T. Pagnier P. Siciliano G. Faglia J.R. Morante 《Advanced functional materials》2006,16(11):1488-1498
Metal oxide (SnO2, TiO2, In2O3, ZnO) sols are prepared by various sol–gel processes in such a way as to hinder the condensation reactions. The obtained sols are injected at 160 °C into a solution of tetradecene and dodecylamine, and kept under heating for different periods of time. Depending on the starting sol, variously crystallized oxide nanoparticles are obtained, whose phase compositions and chemical structure have been studied by X‐ray diffraction (XRD) and Fourier transform IR spectroscopy. The elimination of the organic residuals has been carried out by thermal treatment, and the thermal evolution of the nanoparticles has been studied by thermal analyses and Raman spectroscopy. High‐resolution transmission electron microscopy studies coupled with XRD measurements show that the thermal treatment does not markedly affect the particle size, which remains in the nanometer‐sized regime (from 3.5 to 8.5 nm, depending on the system), except in the case of ZnO. The thermally purified and stabilized powders, drop‐coated onto alumina substrates with pre‐deposited electrical contacts, have been tested as gas‐sensing devices, displaying outstanding sensing properties even at room temperature. 相似文献
96.
A Mu?oz E Bureo JJ Ortega C Richard T Olivé MS Maldonado L Madero MA Díaz 《Canadian Metallurgical Quarterly》1998,83(11):981-984
BACKGROUND AND OBJECTIVE: To compare the estimated survival and disease-free survival between children with Ph1-positive chronic myeloid leukemia treated with allogeneic bone marrow transplantation or conventional chemotherapy. DESIGN AND METHODS: In this retrospective study we compared the results obtained in a group of 14 children who received allogeneic bone marrow transplantation (BMT) between 1983 and 1993, and another group of 27 children treated with busulfan, hydroxyurea or alpha-interferon during the same time period. Patients were transplanted at a median of 7 months from diagnosis and all except one were in their first chronic phase. Conditioning consisted in total body irradiation and cyclophosphamide in 12 cases, and busulfan was added in two. RESULTS: Of the 14 patients treated with BMT, two died of transplant-related complications and two relapsed 18 and 48 months after the BMT. Ten children remain alive and disease free at a median follow up of 60 months. The probability of DFS at 5 years is 70%. Of the 27 patients treated with chemotherapy, 22 have died at a median of 36 months from diagnosis. The probability of survival at 5 years is 5% versus 83% for the BMT group (p = 0.001). INTERPRETATION AND CONCLUSIONS: Allogeneic BMT is a safe and very effective treatment for Ph-positive CML in children. Patients who have an HLA-identical sibling donor must receive a transplant as soon as possible after being diagnosed. 相似文献
97.
Enterocin I (ENTI) is a novel bacteriocin produced by Enterococcus faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation. The bacteriocin is active against many olive spoilage and food-borne gram-positive pathogenic bacteria, including clostridia, propionibacteria, and Listeria monocytogenes. ENTI was purified to homogeneity by ammonium sulfate precipitation, binding to an SP-Sepharose fast-flow column, and phenyl-Sepharose CL-4B and C2/C18 reverse-phase chromatography. The purification procedure resulted in a final yield of 954% and a 170,000-fold increase in specific activity. The primary structure of ENTI was determined by amino acid and nucleotide sequencing. ENTI consists of 44 amino acids and does not show significant sequence similarity with any other previously described bacteriocin. Sequencing of the entI structural gene, which is located on the 23-kb plasmid pEF1 of E. faecium 6T1a, revealed the absence of a leader peptide at the N-terminal region of the gene product. A second open reading frame, ORF2, located downstream of entI, encodes a putative protein that is 72.7% identical to ENTI. entI and ORF2 appear to be cotranscribed, yielding an mRNA of ca. 0.35 kb. A gene encoding immunity to ENTI was not identified. However, curing experiments demonstrated that both enterocin production and immunity are conferred by pEF1. 相似文献
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