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31.
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Dana Petcu Silviu Panica Marc Frîncu Marian Neagul Daniela Zaharie Georgiana Macariu Dorian Gorgan Teodor Ştefănuţ 《Computer Standards & Interfaces》2012,34(6):493-508
Earth observation data processing and storing can be done nowadays only using distributed systems. Experiments dealing with a large amount of data are possible within the timeframe of a lesson and can give trainees the freedom to innovate. Following these trends and ideas, we have built a proof-of-the-concept platform, named GiSHEO, for Earth observation educational tasks. It uses Grid computing technologies to analyze and store remote sensing data, and combines them with eLearning facilities. This paper provides an overview of the GiSHEO's platform architecture and of its technical and innovative solutions. 相似文献
33.
The literature on ‘high reliability organizations’ demonstrates how central reliability is to organizing in certain highly demanding settings. In more mundane settings, however, where there may not be a dominant type of catastrophic failure, the meaning attributed to reliability is less likely to be unambiguous and consensual. It is more likely to be explicitly relational: a quality of the relationship between an entity that is being relied on and an entity that is relying on it. This draws attention to the importance of the relying process in contributing to how a system performs and whether it meets expectations. A field study was carried out in a highway construction and maintenance organization to analyse the various understandings of reliability that organizational members had in different contexts. It found that there were multiple understandings – involving a capacity not only to achieve particular outcomes but also comply with norms, fit behaviour to situations, and communicate about what could and could not be achieved. It also found that reliability problems were not solved in some simple sense. Instead they were transformed into other reliability problems that then had to be managed by further effort or by other organizations. We suggest that recognizing the multiple meanings of reliability, the importance of relying, and the way in which reliability problems are transformed from one form to another all have important practical implications. 相似文献
34.
The effects of the unit corona-treatment energy on the contact angle of various liquids, on the surface free energy, on the extent of oxidation of a surface layer, and on the adhesion of acrylic adhesive were studied using a biaxially-oriented polypropylene (BOPP) film. The surface free energy was determined with the van Oss-Chaudhury-Good (VCG) approach as well as with the wettability method. The extent of oxidation of the surface layer of the corona-treated BOPP film was evaluated with X-ray photoelectron spectroscopy. The adhesion strength of joints between the BOPP film and the acrylic adhesive was measured using the 180°-peel test.
In the range of the unit corona-treatment energy up to 1.2 kJ/m2, a rapid increase in the surface free energy with the treatment energy is observed. In the range above that value, the surface free energy rises relatively slowly. The extent of oxidation of the surface layer and the adhesion strength of joints between the BOPP film and the acrylic adhesive are approximately in direct proportion to the unit energy of the corona treatment. A five-fold growth of the adhesion strength of the studied joints within the examined range of the treatment energy was found. 相似文献
In the range of the unit corona-treatment energy up to 1.2 kJ/m2, a rapid increase in the surface free energy with the treatment energy is observed. In the range above that value, the surface free energy rises relatively slowly. The extent of oxidation of the surface layer and the adhesion strength of joints between the BOPP film and the acrylic adhesive are approximately in direct proportion to the unit energy of the corona treatment. A five-fold growth of the adhesion strength of the studied joints within the examined range of the treatment energy was found. 相似文献
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In this work were determined triclosan and 4n‐nonylphenol in water from a reservoir that is used to provide water to a purification plant in an important city in Colombia. The analytical methodology was validated using solid‐phase extraction and analysis by gas chromatography‐mass spectrometry (GC‐MS). The analysis by GC‐MS showed good linearity in the range of 0.05–5 μg/L for both compounds. Recoveries from 79 to 109% and standard deviations of 2.5–7.7 for low concentrations and from 3.8 to 9.6 (n = 5) for high concentrations were obtained for both compounds. In Colombia, this is the first time that these compounds have been analysed in water supplying of a drinking water treatment plant. The validated method was applied to the analysis of 27 samples collected in August 2010 in 11 locations from the reservoir and in the influent and effluent of the drinking water treatment plant. In total, seven samples were found to contain triclosan. 相似文献
37.
The influence of electron beam irradiation,plastic deformation,and re‐irradiation on crystallinity degree,mechanical and sclerometric properties of GUR 1050 used for arthroplasty 下载免费PDF全文
Adrian Barylski Joanna Maszybrocka Marian Kupka Krzysztof Aniołek Łukasz Mieszczak 《应用聚合物科学杂志》2016,133(28)
The article describes the influence of an electron beam irradiation (I), plastic deformation (D), and re‐irradiation (R) on the properties of ultrahigh molecular weight polyethylene (GUR 1050). It was found that the modification through irradiation entailed a gradual increase in the degree of crystallinity (after irradiation–I). After plastic deformation and re‐irradiation (IDR) the degree of crystallinity decreases which had a direct influence on the mechanical properties. The polymer irradiation only (technique I) resulted in an increase in the maximum stress as compared with the material in the initial state. The application of deformation and re‐irradiation (technique IDR) allowed increasing the deformation resistance by more than 40%. Moreover, the irradiation with an electron beam resulted in the increase in hardness (H) and Young's modulus (E) proportionally to the applied irradiation dose and in the reduction of total indentation work (Wtot) and its components. After deformation and re‐irradiation the polyethylene hardness went down. The application of technique (I) caused an improvement to the material abrasion resistance (reduction of parameter PD–working scratch depth) with the increasing irradiation dose. The introduction of deformation and re‐irradiation did not have a material impact on parameter (PD) increasing at the same time elastic properties of UHMWPE (increase in parameter NPS–elastic recovery). Modification IDR has changed the wear mechanism (β) toward ploughing and has increased the abrasion‐resistance index (Wβ) and also significantly reduced the coefficient of friction (μ) of GUR 1050. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43683. 相似文献
38.
Katarzyna Grzybowska Zaneta Wojnarowska Andrzej Grzybowski Marian Paluch Juan M. Giussi M. Susana Cortizo Iwona Blaszczyk-Lezak Carmen Mijangos 《Polymer》2014
In this paper, dielectric and calorimetric studies of the small-molecule glass former allyl acetoacetate monomers as well as its newly synthetized homopolymer and copolymers with different styrene composition were performed in both the liquid and glassy states. The molecular dynamics studies by the broadband dielectric spectroscopy and the stochastic temperature modulated differential scanning calorimetry enabled us to explore relaxation processes of examined materials in the wide frequency range. We found that the copolymers reveal two co-existing glass transitions characterized by the glass transition temperatures, which are very close to those of the corresponding homopolymers. These results suggest that the copolymers exhibited some sequences of acetoacetate units with a microphase-separated morphology in agreement with the value of reactivity ratio previously determined. We investigated effects of copolymerization compositions on the glass transition temperature, the isobaric fragility index, the dielectric and calorimetric intensity, and the dynamic heterogeneity on the glass transitions of the materials. 相似文献
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40.
Vladimír Matlach Daniel Dostl Marian Novotný 《International journal of molecular sciences》2022,23(3)
This article examines the presence of the empirical tendency known as the Menzerath–Altmann Law (MAL) on protein secondary structures. MAL is related to optimization principles observed in natural languages and in genetic information on chromosomes or protein domains. The presence of MAL is examined on a non-redundant dataset of 4728 proteins by verifying significant, negative correlations and testing classical and newly proposed formulas by fitting the observed trend. We conclude that the lengths of secondary structures are specifically dependent on their number inside the protein sequence, while possibly reflecting the formula proposed in this paper. This behavior is observed on average but is individually avoidable and possibly driven by a latent cost function. The data suggest that MAL could provide a useful guiding principle in protein design. 相似文献