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21.
Rigaud V. Coste-Maniere E. Aldon M.J. Probert P. Perrier M. Rives P. Simon D. Lang D. Kiener J. Casal A. Amar J. Dauchez P. Chantler M. 《Robotics & Automation Magazine, IEEE》1998,5(1):25-35
The main goal of the UNION ESPRIT Basic Research Action is to develop methods for increasing the autonomy and intelligence of underwater remotely operated vehicles (ROVs). The project focuses mainly on the development of coordinated control and sensing strategies for combined manipulator and vehicle systems. Both fundamental theories and methods for the design of these heterogeneous systems are investigated. A complex canonical mission in the field of offshore inspection maintenance and repair tasks was chosen as an integration guideline of all the results 相似文献
22.
Bond Between Near-Surface Mounted Carbon-Fiber-Reinforced Polymer Laminate Strips and Concrete 总被引:1,自引:0,他引:1
José Manuel de Sena Cruz Joaquim António Oliveira de Barros 《Canadian Metallurgical Quarterly》2004,8(6):519-527
In recent years, a strengthening technique based on near-surface mounted (NSM) laminate strips of carbon-fiber-reinforced polymer (CFRP) has been used to increase the load-carrying capacity of concrete and masonry structures by introducing laminate strips into precut grooves on the concrete cover of the elements to be strengthened. The high experimentally derived levels of strength efficacy with concrete columns, beams, and masonry panels have presented NSM as a viable and promising technique. This practice requires no surface preparation work and, after cutting the groove, requires minimal installation time compared to the externally bonded reinforcing technique. A further advantage associated with NSM CFRP is its ability to significantly reduce the probability of harm resulting from fire, acts of vandalism, mechanical damage, and aging effects. To assess the bond behavior of CFRP to concrete, pullout-bending tests have been carried out. The influences of bond length and concrete strength on bond behavior are analyzed, the tests are described, and the results are presented and discussed in detail. Finally, a local stress-slip relationship is determined based on both experimental results and a numerical strategy. 相似文献
23.
Joaquim Salvi Author Vitae Jordi Pagès Author Vitae Author Vitae 《Pattern recognition》2004,37(4):827-849
Coded structured light is considered one of the most reliable techniques for recovering the surface of objects. This technique is based on projecting a light pattern and viewing the illuminated scene from one or more points of view. Since the pattern is coded, correspondences between image points and points of the projected pattern can be easily found. The decoded points can be triangulated and 3D information is obtained. We present an overview of the existing techniques, as well as a new and definitive classification of patterns for structured light sensors. We have implemented a set of representative techniques in this field and present some comparative results. The advantages and constraints of the different patterns are also discussed. 相似文献
24.
Zheng Liu Xin-Hao Zhang Borja Callejas-Díaz Joaquim Mullol 《International journal of molecular sciences》2016,17(5)
The concept of united airway diseases (UAD) has received increasing attention in recent years. Sustained and increased inflammation is a common feature of UAD, which is inevitably accompanied with marked gene modification and tight gene regulation. However, gene regulation in the common inflammatory processes in UAD remains unclear. MicroRNA (miRNA), a novel regulator of gene expression, has been considered to be involved in many inflammatory diseases. Although there are an increasing number of studies of miRNAs in inflammatory upper and lower airway diseases, few miRNAs have been identified that directly link the upper and lower airways. In this article, therefore, we reviewed the relevant studies available in order to improve the understanding of the roles of miRNAs in the interaction and pathogenesis of UAD. 相似文献
25.
Enriqueta Casal Rosa Lebrón-Aguilar Yuan Chuan-Lee Tomiya Noboru Jesús Eduardo Quintanilla-López 《Food Analytical Methods》2013,6(3):814-825
Isolation and characterization of oligosaccharides from caseinomacropeptide (CMP) are important in understanding the biological and functional properties of CMP. However, it is difficult to achieve this goal, due to the high degree of isomerism present in these types of compounds. In this study, the sialylated oligosaccharides derived from ovine and caprine CMP were released as oligosaccharide alditols by reductive β-elimination and subsequently separated and characterized using graphite carbon column liquid chromatography–negative electrospray ionization ion trap tandem mass spectrometry (LC/ESI(?)-MSn). Although, the chromatographic resolution of isomeric oligosaccharides was not achieved perfectly, the characteristic tandem mass spectra of these compounds allowed differentiating and confirming unequivocally the structure of each one of the oligosaccharides. In CMP of both species, four trisaccharides and four tetrasaccharides were identified as O-glycans. Their chemical structures were identified to be Galβ1-3(NeuAcα2-6)GalNAcol, NeuAcα2-3Galβ1-3GalNAcol, Galβ1-3(NeuGcα2-6)GalNAcol, NeuGcα2-3Galβ1-3GalNAcol, NeuAcα2-3Galβ1-3(NeuGcα2-6)GalNAcol, NeuGcα2-3Galβ1-3(NeuAcα2-6)GalNAcol, NeuAcα2-3Galβ1-3(NeuAcα2-6)GalNAcol, and NeuGcα2-3Galβ1-3(NeuGcα2-6)GalNAcol. The LC/MSn methodology using an ion trap-type mass analyzer shown in this study is of general applicability for determination of short O-glycan oligosaccharides. 相似文献
26.
Laura Cherta Joaquim Beltran Francisco López Félix Hernández 《Food Analytical Methods》2013,6(4):1170-1187
A fast gas chromatography–mass spectrometry method has been developed for multiresidue determination of up to 56 pesticides in fruits and vegetables in a chromatographic run time of <10 min, using a single quadrupole mass spectrometer operating in selected ion monitoring mode. The well-known acetate-buffering version of the QuEChERS method has been used for sample preparation. Programmable temperature vaporizer injection of 3 μL allowed reaching limits of detection between 0.15 and 15 μg/kg for most compounds in the sample matrices tested. The applicability of the method has been evaluated in apple, orange, carrot, and tomato. Recoveries at three fortification levels (0.01, 0.1 and 0.5 mg/kg) ranged from 70 to 120 % for most compounds, with relative standard deviations below 20 % in all cases. The developed method has been applied to fruit and vegetable samples from different Spanish provinces. 相似文献
27.
Joaquim Montezuma 《Housing Studies》2006,21(6):883-908
This paper provides evidence about institutional investors' attitudes and perceptions of residential property as an investment asset group in three European countries (Switzerland, the Netherlands and Sweden). These countries stand out, with an extraordinarily large institutional residential ownership, in fact, residential institutional allocation represents about 6 per cent, 2 per cent and 3 per cent of the total institutional investment in Switzerland, the Netherlands and Sweden, respectively. Housing is the most important institutional property asset type in Switzerland and the Netherlands, comprising over 52 per cent and 50 per cent of their institutional property portfolios, respectively. In Sweden residential property plays an important, but not dominant role in the domestic institutional property portfolios, representing about 21 per cent of the institutional property holdings. Using a postal survey of representatives of pension funds, insurance companies, property investment and asset management companies the study analyses the attractiveness of residential property in terms of institutional investment goals. The survey examines the institutional investors' perceptions of housing investment, namely with respect to its returns, volatility, inflation hedging, liabilities matching and correlation with shares, bonds and non-residential property. Additionally, the survey looks at the institutional investors' experiences regarding the private rented sector. The survey suggests that investment in residential property equity is likely to be done through larger portfolios, which tend to invest in housing directly. Residential property is seen mainly as an earning asset group able to provide diversification benefits for investors even when portfolios already include non-residential property. The respondents are mainly concerned with rent regulation issues, the lack of well-structured investment vehicles is undoubtedly a less important problem. 相似文献
28.
Stress and strain distribution in demineralized enamel: A micro‐CT based finite element study 下载免费PDF全文
Aline Almeida Neves Eduardo Coutinho Haimon Diniz Lopes Alves Joaquim Teixeira de Assis 《Microscopy research and technique》2015,78(10):865-872
Physiological oral mechanical forces may play a role on the progression of enamel carious lesions to cavitation. Thus, the aim of this study was to describe, by 3D finite element analysis, stress, and strain patterns in sound and carious enamel after a simulated occlusal load. Micro‐CT based models were created and meshed with tetrahedral elements (based on an extracted third molar), namely: a sound (ST) and a carious tooth (CT). For the CT, enamel material properties were assigned according to the micro‐CT gray values. Below the threshold corresponding to the enamel lesion (2.5 g/cm3) lower and isotropic elastic modulus was assigned (E = 18 GPa against E1 = 80 GPa, E2 = E3 = 20 GPa for sound enamel). Both models were imported into a FE solver where boundary conditions were assigned and a pressure load (500 MPa) was applied at the occlusal surface. A linear static analysis was performed, considering anisotropy in sound enamel. ST showed a more efficient transfer of maximum principal stress from enamel to the dentin layer, while for the CT, enamel layer was subjected to higher and concentrated loads. Maximum principal strain distributions were seen at the carious enamel surface, especially at the central fossa, correlating to the enamel cavity seen at the original micro‐CT model. It is possible to conclude that demineralized enamel compromises appropriate stress transfer from enamel to dentin, contributing to the odds of fracture and cavitation. Enamel fracture over a dentin lesion may happen as one of the normal pathways to caries progression and may act as a confounding factor during clinical diagnostic decisions. Microsc. Res. Tech. 78:865–872, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
29.
30.
Gema Casal Xavier Monteys John Hedley Paul Harris Conor Cahalane Tim McCarthy 《International journal of remote sensing》2019,40(8):2855-2879
Bathymetry estimated from optical satellite imagery has been increasingly implemented as an alternative to traditional bathymetric survey techniques. The availability of new sensors such as Sentinel-2 with improved spatial and temporal resolution, in comparison with previous optical sensors, offers innovative capabilities for bathymetry derivation. This study presents an assessment of the fit between satellite data and the underlying models in the most widely used empirical algorithms: the linear band model and the log-transformed band ratio model using Sentinel-2A data. Both models were tested in two study areas of the Irish coast with different morphological and environmental conditions. Results showed that the linear band model fitted better than the log-transformed band ratio model providing coefficient of determination values, R2, between 0.83 and 0.88 (0 m–10 m) for the five images considered in the study. The closest fit was found in the depth range 2 m–6 m. Atmospheric correction, bottom type influence, and water column conditions proved to be key factors in the bathymetric derivation using these satellite datasets. 相似文献