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151.
We have detected the lack of a widely accepted knowledge representation model in the area of Blood Vessel analysis. We find that such a tool is needed for the future development of the field and our own research efforts. It will allow easy reuse of software pieces through appropriate abstractions, facilitating the development of innovative methods, procedures and applications. We include a thorough review of vascular morphology image analysis. After the identification of the key representation elements and operations, we propose a Vessel Knowledge Representation (VKR) model that would fill this gap. We give insights into its implementation based on standard Object-Oriented Programming tools and paradigms. The VKR would easily integrate with existing medical imaging and visualization software platforms, such as the Insight ToolKit (ITK) and Visualization Toolkit (VTK). 相似文献
152.
This article provides jet fuel demand projections at the worldwide level and for eight geographical zones until 2025. Air traffic forecasts are performed using dynamic panel-data econometrics. Then, the conversion of air traffic projections into quantities of jet fuel is accomplished by using a complementary approach to the ‘Traffic Efficiency’ method developed previously by the UK Department of Trade and Industry to support the Intergovernmental Panel on Climate Change ( IPCC, 1999). According to our main scenario, air traffic should increase by about 100% between 2008 and 2025 at the world level, corresponding to a yearly average growth rate of 4.7%. World jet fuel demand is expected to increase by about 38% during the same period, corresponding to a yearly average growth rate of 1.9% per year. According to these results, energy efficiency improvements allow reducing the effect of air traffic rise on the increase in jet fuel demand, but do not annihilate it. Jet fuel demand is thus unlikely to diminish unless there is a radical technological shift, or air travel demand is restricted. 相似文献
153.
S. Vallon P. Chevallier L. Guiziou G. Alibert L.S.H.K. Chun N. Boos 《Photonics Technology Letters, IEEE》2003,15(4):554-556
A 40-band integrated static gain-flattening filter (GFF) is presented. The design of the filter was optimized using a newly developed analytical model, which shows a good agreement with the experimental results. The filter has a low insertion loss of 4.1 dB, an attenuation range that exceeds 20 dB, and is able to generate slopes above 20 dB/nm. It is a first step toward an integrated high-resolution dynamic GFF. 相似文献
154.
Cornu S Montagne D Maguin F Lay CL Chevallier P Cousin I 《The Science of the total environment》2007,377(2-3):244-254
In this paper we studied the nature and hierarchy of the processes responsible for soil evolution as a function of land use (forest and culture). Albeluvisols were chosen as a pedological model for this study. Iron, manganese, calcium, potassium and trace elements were used as indicators of the soil processes. Their spatial distribution was mapped along tongues of Albeluvisols at a pluri-centimetric scale, using X-ray microfluorescence. In both land use, Fe distribution was shown to be closely related to the soil colour variation along the tongues. Nickel and Cu followed the same distribution. Zinc was almost functioning as Fe with the difference that this element was not lost from the transition zone identified between the bleached tongues and the ochre volumes representative of the illuvial horizon. Under forest, the Fe and Mn redox fronts were closely associated that allows mapping them on the same thin section. Manganese disappeared from the neighbourhood of the iron redox front under agriculture. This was interpreted as a slow down of the iron redox process due to pH increase while Mn redox process was not modified. In addition, under forest, Ca seems totally leached. Liming causes an increase of Ca concentrations in the whole soil profile. This Ca is in an exchangeable form principally located at the interface between white and ochre volumes. We concluded that by liming, Man induced drastic changes in the kinetic of redox process in Albeluvisols over 200 years showing at the same time the extreme rapidity of these processes. 相似文献
155.
9月17日,博通公司的无线连接集团高级总监Rahul Patel先生接受了本刊记者关于802.11n相关问题的采访。在采访中,Rahul Patel首先向记者介绍了Wi—Fi技术的发展情况以及Wi—Fi联盟目前的工作进展。他介绍说:“做为互联网世界的必然衍生产物,在过去4、5年中,Wi—Fi逐渐地集成到基于尖端通信半导体的消费类电子产品当中,其作用也开始显现。 相似文献
156.
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158.
Xinshen Du Yinping Li Xing Liu Xiong Wang Celine Huselstein Yanteng Zhao Peter R. Chang Yun Chen 《Journal of materials science. Materials in medicine》2014,25(3):823-833
Polyurethane prepolymer (PUP) was first synthesized from polycaprolactone diol and isophorone diisocyanate; and then a series of zein-based polyurethane (ZEPU) sheets was fabricated from PUP and zein (ZE) using a hot press and moulding process without addition of other additives. Effects of ZE content (WZE) on the structure and properties of the resultant ZEPU sheets were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, dynamic mechanical analysis, tensile testing, and dissolubility testing in alcohol. The results indicated that cross-linking and grafting reactions occurred between ZE and PUP to form new polyurethane showing a higher thermal stability, flexibility, and alcohol-resistance than the neat ZE sheets. For example, the elongation at break of ZEPU with 50 % WZE was 211.2 %, which was 47 times higher than that of neat ZE sheet. ZE molecules acted as both cross-linkers and polymer fillers in ZEPU sheets. The cytotoxicity and cytocompatibility of ZEPU sheets were evaluated by cell culture in vitro. The ZEPU sheets showed non- or low-cytotoxicity, and L929 cells grew and expanded well on the surfaces of the sheets with WZE over 50 %. Undoubtedly, the fabrication of ZE-based polyurethanes without toxic additives such as catalysts, cross-linkers and chain extenders improved the physical properties and cytocompatibility of zein, thus widening the possible range of applications for zein-based biomaterials. 相似文献
159.
T Bizollon S Guichard SN Ahmed P Chevallier C Ducerf M Sepetjan J Baulieux C Trepo 《Canadian Metallurgical Quarterly》1998,29(6):893-900
Large-scale DNA sequencing is creating a sequence infrastructure of great benefit to protein biochemistry. Concurrent with the application of large-scale DNA sequencing to whole genome analysis, mass spectrometry has attained the capability to rapidly, and with remarkable sensitivity, determine weights and amino acid sequences of peptides. Computer algorithms have been developed to use the two different types of data generated by mass spectrometers to search sequence databases. When a protein is digested with a site-specific protease, the molecular weights of the resulting collection of peptides, the mass map or fingerprint, can be determined using mass spectrometry. The molecular weights of the set of peptides derived from the digestion of a protein can then be used to identify the protein. Several different approaches have been developed. Protein identification using peptide mass mapping is an effective technique when studying organisms with completed genomes. A second method is based on the use of data created by tandem mass spectrometers. Tandem mass spectra contain highly specific information in the fragmentation pattern as well as sequence information. This information has been used to search databases of translated protein sequences as well as nucleotide databases such as expressed sequence tag (EST) sequences. The ability to search nucleotide databases is an advantage when analyzing data obtained from organisms whose genomes are not yet completed, but a large amount of expressed gene sequence is available (e.g., human and mouse). Furthermore, a strength of using tandem mass spectra to search databases is the ability to identify proteins present in fairly complex mixtures. 相似文献
160.
L Ginot N Ait-Bouali M Besse P Chevallier F Goldberg J Buisson 《Canadian Metallurgical Quarterly》1997,9(4):379-396
We know better the violences made by the youngs than those they suffer from. The purpose of this study is to assess, as for a city surrounding Paris, the prevalence of the violences they felt and its relation with the psychic uneasiness. Some 344 youngs (from 15 to 25 years old) selected in the city, have filled in an autoquestionnaire. It has shown that 61.6% of them have already suffered from violences, among them 44.5% from adults and what is more from institutional adults. 13.7% of the selected youngs were victims of regular violences in school sphere and 12.8% in urban environment. The expression of a psychic uneasiness is linked to the previous violences they have felt. The feeling of call for help by a psychologist or a psychiatrist is in relation with the past psychic discomfort and not with the past suffered violences. 相似文献