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81.
Jeffery Karafa Mihalis M. Golias Stephanie Ivey Georgios K. D. Saharidis Nikolaos Leonardos 《The International Journal of Advanced Manufacturing Technology》2013,65(1-4):473-484
In this paper, the berth allocation problem with stochastic vessel handling times is formulated as a bi-objective problem. To solve the resulting problem, an evolutionary algorithm-based heuristic and a simulation-based Pareto front pruning algorithm is proposed. Computational examples show that the proposed approach provides solutions superior to the ones where the expected value of the vessel handling times is used. 相似文献
82.
Multi-Camera Human Activity Monitoring 总被引:1,自引:0,他引:1
Loren Fiore Duc Fehr Robot Bodor Andrew Drenner Guruprasad Somasundaram Nikolaos Papanikolopoulos 《Journal of Intelligent and Robotic Systems》2008,52(1):5-43
With the proliferation of security cameras, the approach taken to monitoring and placement of these cameras is critical. This
paper presents original work in the area of multiple camera human activity monitoring. First, a system is presented that tracks
pedestrians across a scene of interest and recognizes a set of human activities. Next, a framework is developed for the placement
of multiple cameras to observe a scene. This framework was originally used in a limited X, Y, pan formulation but is extended to include height (Z) and tilt. Finally, an active dual-camera system for task recognition at multiple resolutions is developed and tested. All
of these systems are tested under real-world conditions, and are shown to produce usable results.
This work has been supported by the NSF through grants #IIS-0219863, #CNS-0224363, #CNS-0324864, #IIP-0443945, #CNS-0420836,
#IIP-0726109, and #CNS-0708344. 相似文献
83.
Nikolaos Dimitratos Jose Antonio Lopez-Sanchez Graham J. Hutchings 《Topics in Catalysis》2009,52(3):258-268
The use of renewable feedstocks, derived from biomass, for the chemical industry is discussed. The modern chemical industry
is based around platform chemicals, e.g. ethene, propene, benzene and xylenes, which are readily derived from oil, and using
these intermediates a broad range of finished products can be derived. While it is feasible that biomass can be converted
to syngas and hence to existing key platform chemicals, this loses all of the chemical complexity that is inherent in bio-derived
molecules. In this paper some of the options are considered and, in particular, the oxidation of glucose and glycerol using
gold nanoparticles supported on carbon is described. We also contrast the oxidation of glycerol using supported gold and gold–palladium
alloys prepared using an impregnation technique, since the gold–palladium alloys have been shown to be highly effective for
the oxidation of alcohols and the synthesis of hydrogen peroxide. 相似文献
84.
Vaios T. Karathanos Ioannis Mourtzinos Konstantina Yannakopoulou Nikolaos K. Andrikopoulos 《Food chemistry》2007,101(2):652-658
In the present study, complexes of vanillin with β-cyclodextrin (β-CD) were prepared by the freeze-drying method. The formation of the inclusion complex was confirmed by differential scanning calorimetry (DSC). DSC thermograms indicated that the endothermic peak of vanillin and the physical mixture of vanillin with β-CD, due to the melting of vanillin crystals, were absent in DSC thermograms obtained for the freeze-dried inclusion complex. Moreover, the DSC studies under oxidation conditions indicate that the complex of vanillin with β-CD is protected towards oxidation since it remains intact at temperatures where the free vanillin is oxidising. The structure of the complex in aqueous solutions was established by nuclear magnetic resonance (NMR) studies and specifically by two-dimensional rotational frame NOE spectra. NMR studies showed inclusion of the entire vanillin molecule in the β-CD in a tilted manner and with the aldehyde group in the primary side. The stoichiometry of the complex was 1:1. A phase solubility study was performed by mixing an excess amount of vanillin with aqueous solutions containing increasing amounts of β-CD. The results indicated that the complex of a vanillin/β-CD inclusion is more soluble in water than vanillin alone. 相似文献
85.
Autonomous stair-climbing with miniature jumping robots. 总被引:1,自引:0,他引:1
Sascha A Stoeter Nikolaos Papanikolopoulos 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2005,35(2):313-325
The problem of vision-guided control of miniature mobile robots is investigated. Untethered mobile robots with small physical dimensions of around 10 cm or less do not permit powerful onboard computers because of size and power constraints. These challenges have, in the past, reduced the functionality of such devices to that of a complex remote control vehicle with fancy sensors. With the help of a computationally more powerful entity such as a larger companion robot, the control loop can be closed. Using the miniature robot's video transmission or that of an observer to localize it in the world, control commands can be computed and relayed to the inept robot. The result is a system that exhibits autonomous capabilities. The framework presented here solves the problem of climbing stairs with the miniature Scout robot. The robot's unique locomotion mode, the jump, is employed to hop one step at a time. Methods for externally tracking the Scout are developed. A large number of real-world experiments are conducted and the results discussed. 相似文献
86.
87.
88.
Nick Kalogeropoulos Nikolaos K Andrikopoulos Maria Hassapidou 《Journal of the science of food and agriculture》2004,84(13):1750-1758
The effect of domestic pan‐frying in virgin olive oil (VOO) on the proximate composition, energy content, cholesterol, squalene and fatty acids in the edible portion of six species of finfish, common squid and mussels just caught from several regions of the Aegean Sea (Mediterranean Sea) was investigated. The species selected are traditionally consumed pan‐fried in VOO by the Greeks. On a fresh weight basis, pan‐frying caused significant water loss and increase of total fat, crude protein and energy content. The amount of VOO absorbed during frying ranged from 4.5 to 14.2% of fresh matter, showing a non‐linear negative correlation with initial fat, fish length and fish weight. Cholesterol content increased from 25 to 106 mg 100 g?1 fresh weight (fw) to 33–130 mg 100 g?1 fw after frying. VOO absorbed during frying resulted in a 20–78 times increase of squalene content and in significant alteration of fatty acid composition, the major change being the increase of monounsaturated fatty acids which became predominant in all fried samples. The intakes of fat and major fatty acid classes by consuming the pan‐fried seafood were comparable with the respective average Greek values. Frying in VOO resulted in a two to three times decrease of the atherogenic index and a slightly less decrease of the thrombogenic index. Both indices remained lower than 0.45 in all fried samples. The cholesterol‐saturated fat index and the cholesterol index increased up to twice after frying, ranging between 3.4–9.9 and 2.9–9.3, respectively. From the results obtained it is concluded that fish and shellfish pan‐fried in VOO present a healthy lipid profile in terms of the n‐6/n‐3 ratio, major fatty acid classes and total fat content. Copyright © 2004 Society of Chemical Industry 相似文献
89.
Implementation of quality control methods in conjunction with chemometrics toward authentication of dairy products 总被引:2,自引:0,他引:2
The implementation of novel and accurate quality and safety control methods in conjunction with chemometrics in various fields of science, particularly in food science, showed that this combination stands for a very powerful tool for detecting food authenticity. The latter reflects both geographic origin and variety. Dairy products, in particular, have repeatedly worried the public authorities in terms of authentication regarding origin and in view of the many illnesses occasionally due to products of specific origin. Therefore, the development of a robust and reliable system endowed with this discriminatory power (varietal and/or geographic) is of great importance, both in terms of public health and consumer protection. 相似文献
90.
Maria Koutsoupidou Irene S. Karanasiou Nikolaos Uzunoglu 《Journal of Computational Electronics》2014,13(3):593-598
Metamaterials are artificial materials offering unique properties which render them useful for various applications. In the present paper, we examine whether it is possible to design a split ring resonators’ (SRRs) based metamaterial substrate for enhancing the performance of planar antennas operating at THz frequencies. Initially, the radiating characteristics of a simple rectangular patch antenna over two well-known SRR substrates are studied. The yielded results are then compared to those of two novel designs of metamaterial antenna substrate with SRRs of decreasing size which are proposed to improve the antenna’s performance. 相似文献