排序方式: 共有582条查询结果,搜索用时 31 毫秒
121.
The automated real-time detection and classification of cetacean and anthropogenic sounds from deep-sea observatories can play a key role to study cetaceans in the field, to quantify the impact of anthropogenic sounds or to initiate mitigation measures during potentially harmful human activities. In the area of the NEMO-ONDE deep-sea observatory, sperm whales are often present together with heavy shipping. The spatial coincidence of both sound sources allows for the long term monitoring of their interaction. Some ships produce impulsive sounds and the automated separation of these impulses from sperm whale clicks is not a trivial task. As part of a detection, classification and localisation system for acoustic data from marine observatories, we present four modules performing the automated real-time classification of clicks from sperm whales and impulsive sounds produced by ships. First, two modules detect segments that contain impulsive sounds within a specifiable frequency band and return the impulses’ positions. Then, two modules classify the detected impulses as sperm whale clicks or ship impulses. Finally, at the level of 22 s segments, the classification outputs from individual impulses are combined into a decision on the presence of sperm whale clicks or ship impulses. The modules’ reliability was tested on data from the NEMO-ONDE observatory. Training and testing data were separated by more than 2 months, enabling to assess the consistency of the predictions over the long term. The automated separation between segments of the two classes was high with area under the ROC curve (AUC) values between 0.94 and 0.98. 相似文献
122.
Suvabrata Das Author VitaeKwok Fai CheungAuthor Vitae 《Wave Motion》2012,49(1):181-197
The steady forward motion of a marine vessel modifies the incident and scattered waves as well as its dynamic characteristics in a seaway. Small amplitude assumptions of the surface waves and vessel dynamic responses lead to linearization of the potential flow problem and its solution in the frequency domain. The mathematical formulation adopts a translating coordinate system at the vessel forward speed. The free surface boundary condition accounts for the modification of the uniform current around the vessel and a new radiation condition takes into account the Doppler shift of the scattered waves. A boundary element model, based on the Rankine source distribution, describes the steady and oscillatory flows around the vessel. Stokes’ theorem allows evaluation of the surface integrals involving the so-called m-terms due to oscillation of the vessel in a current. Through a numerical experiment with a Wigley hull form, we establish the convergence of the numerical model, verify the radiation condition, and examine the scattered wave patterns for a full range of forward speeds. Previous laboratory data provides validation of the computed hydrodynamic coefficients and dynamic response as well as the potential flow model for general seakeeping applications. 相似文献
123.
Capillary gel electrophoresis (CGE) has been used for protein separation for more than two decades. Due to the technology advancement, current CGE methods are becoming more and more robust and reliable for protein analysis, and some of the methods have been routinely used for the analysis of protein-based pharmaceuticals and quality controls. In light of this progress, we survey 147 papers related to CGE separations of proteins and present an overview of this technology. We first introduce briefly the early development of CGE. We then review the methodology, in which we specifically describe the matrices, coatings, and detection strategies used in CGE. CGE using microfabricated channels and incorporation of CGE with two-dimensional protein separations are also discussed in this section. We finally present a few representative applications of CGE for separating proteins in real-world samples. 相似文献
124.
Daniela KretschyAuthor Vitae Gunda KoellenspergerAuthor VitaeStephan Hann 《Analytica chimica acta》2012
This article reviews novel quantification concepts where elemental labelling is combined with flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS) or liquid chromatography inductively coupled plasma mass spectrometry (LC–ICP-MS), and employed for quantification of biomolecules such as proteins, peptides and related molecules in challenging sample matrices. In the first sections an overview on general aspects of biomolecule quantification, as well as of labelling will be presented emphasizing the potential, which lies in such methodological approaches. In this context, ICP-MS as detector provides high sensitivity, selectivity and robustness in biological samples and offers the capability for multiplexing and isotope dilution mass spectrometry (IDMS). Fundamental methodology of elemental labelling will be highlighted and analytical, as well as biomedical applications will be presented. A special focus will lie on established applications underlining benefits and bottlenecks of such approaches for the implementation in real life analysis. Key research made in this field will be summarized and a perspective for future developments including sophisticated and innovative applications will given. 相似文献
125.
Chungkyun Kim Eunmi Park 《Journal of polymer science. Part A, Polymer chemistry》2001,39(13):2308-2314
Dendritic carbosilanes containing benzoxazole, quinoline, and pyrone derivatives on the periphery were prepared. The parent dendrimers in the inner shell were prepared by the use of iterative hydrosilation and alkenylation cycles. The end generations were obtained by the reaction of terminal Si? Cl groups on each periphery with HOR [HOR = 2‐(2‐hydroxyphenyl)‐benzoxazole, 8‐hydroxyquinoline, and 3‐hydroxy‐2‐methyl‐4‐pyrone] in the presence of amine. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2308–2314, 2001 相似文献
126.
127.
128.
129.
130.