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121.
Lamoussa J. Kere Sousso Kelouwani Kodjo Agbossou Yves Dubé Nilson Henao Raymond Courteau 《International Journal of Hydrogen Energy》2014
This paper investigates a hydrogen-based genset maximum efficiency tracking problem in the context of electric vehicle range extension. This genset is cheaper than fuel cells and has the desirable property of being greenhouse gas emission free in addition to being less pollutant than the conventional gasoline based gensets. Using Taylor's series, a parametric efficiency model is built iteratively. This model is used by a nonlinear optimization method which searches for the optimal operating conditions for a maximum achievable efficiency. The root-mean-square-error between experimental data and the model is less than 5 × 10−4. The hardware-in-the-loop simulation demonstrated that the proposed tracking approach is effective. In addition, it can improve the hydrogen-based genset efficiency up to 7.15% compared to the commonly used industrial method based on a constant speed drive approach. 相似文献
122.
Nadine Gobron Bernard Pinty Michel Verstraete Yves Govaerts 《International journal of remote sensing》2013,34(9):1917-1927
This paper describes the physical and mathematical approach followed to design a vegetation index optimized for the Medium Resolution Imaging Spectrometer (MERIS) sensor, i.e. the MERIS Global Vegetation Index (MGVI). It complements an earlier feasibility study presented elsewhere in this issue by Govaerts and collaborators. Specifically, the crucial issue of the dependency of the vegetation index on changes in illumination and observing geometries is addressed, together with the atmospheric contamination problem. The derivation of the optimal MGVI index formulae allows a comparison of its performance with that of the widely used Normalized Difference Vegetation Index (NDVI), both from a theoretical and an experimental point of view. Data collected by the MOS/IRS-P3 instrument since March 1996 in spectral bands analogous to those that will be available from MERIS can be used to evaluate the MVGI. 相似文献
123.
Some limitations of three dimensional Navier-Stokes Characteristic Boundary Conditions (3D-NSCBC) are discussed for flows traveling in a direction that is oblique to the boundary. To limit errors generated at boundaries with flows having any arbitrary direction, it is proposed to organize the wave decomposition in a coordinate system that is attached to the local flow streamline crossing the boundary, because some modeled expressions are not frame independent. Compared to previous 3D-NSCBC, the modified strategy accounting for oblique waves is found to improve the outflow treatment for transverse outgoing vortices, up to vortices crossing an outflow corner. The method is also applied to an expanding laminar flame. 相似文献
124.
Solenne Taront Audrey Dieudonné Simon Blanchard Pascale Jeannin Philippe Lassalle Yves Delneste Philippe Gosset 《Particle and fibre toxicology》2009,6(1):9
Background
The exposure to pollutants such as diesel exhaust particles (DEP) is associated with an increased incidence of respiratory diseases. However, the mechanisms by which DEP have an effect on human health are not completely understood. In addition to their action on macrophages and airway epithelial cells, DEP also modulate the functions of dendritic cells (DC). These professional antigen-presenting cells are able to discriminate unmodified self from non-self thanks to pattern recognition receptors such as the Toll like Receptors (TLR) and Scavenger Receptors (SR). SR were originally identified by their ability to bind and internalize modified lipoproteins and microorganisms but also particles and TLR agonists. In this study, we assessed the implication of SR in the effects of DEP associated or not with TLR agonists on monocyte-derived DC (MDDC). For this, we studied the regulation of CD36, CXCL16, LOX-1, SR-A1 and SR-B1 expression on MDDC treated with DEP associated or not with TLR2, 3 and 4 ligands. Then, the capacity of SR ligands (dextran sulfate and maleylated-ovalbumin) to block the effects of DEP on the function of lipopolysaccharide (LPS)-activated DC has been evaluated. 相似文献125.
Many embedded systems and consumer appliances require high performance at extremely low price points, and they need them yesterday! Meeting these needs is the latest challenge for system and processor architects. SandCraft recognized this challenge early on and developed the Montage architecture to meet these needs and generate revenue that fuels business growth. Montage implements MIPS-compatible processors for license to MIPS licensees. We have implemented two Montage incarnations now on the market: the SR1 and the SR1-GX high-performance microprocessor cores. Other designs are in the pipeline. With the intellectual property in place, the architecture will proliferate and show that low cost and flexibility do not have to come at the cost of compromising performance. Here, we describe the philosophy behind the development of the Montage architecture and illustrate some of the thinking that resulted in this processor line 相似文献
126.
High molecular weight poly(tert. butyl acrylate) s have been synthesized anionically using a technique derived from that of Teyssié et al. It was established that under proper conditions the sites remained living, allowing proper control of the molecular weight and yielding samples with narrow molecular weight distributions. 相似文献
127.
K.D. Choquette G. Hasnain Y.H. Wang J.D. Wynn R.S. Freund A.Y. Cho R.E. Leibenguth 《Photonics Technology Letters, IEEE》1991,3(10):859-862
GaAs quantum well vertical-cavity surface emitting lasers fabricated using low damage reactive ion etching are discussed. Lasers which are partially and completely etched through their structure are compared. The surface recombination velocity of exposed GaAs is not exacerbated in deep etched lasers; other loss mechanisms in shallow etched lasers have comparable impact on laser performance. Etched lasers exhibit low voltage and small differential series resistance at threshold, while devices fabricated by a combination of etching and ion implantation possess lower threshold current. It is found that reactive ion etching has little additional effect on laser operation, whereas the different device structures considered do influence laser performance.<> 相似文献
128.
ELECTROLESS METALLIZATION of insulatingmaterials is currently used in industry since severaldecades.In its most common applications it consists ina redox reaction between Ni(+2)or Cu(+2)ions and astrong reducer(respectively hypophosphite,H2PO2,forNi(+2)and formaldehyde,HCHO,for Cu(+2))bothcontained in the same solution.The reaction initiationis generally catalyzed by palladium,then the redoxreaction goes on thanks to the remarkable property ofNi and Cu in their metallic state to … 相似文献
129.
Ioana G Carabin Michael R Lyon Simon Wood Xavier Pelletier Yves Donazzolo George A Burdock 《Nutrition journal》2009,8(1):9
Background
The relationship of dietary fiber to overall health is of great importance, as beneficial effects have been demonstrated with the use of fiber from diverse sources, some traditional, other novel. PolyGlycopleX? (PGX?) is a unique proprietary product composed of three water-soluble polysaccharides, that when processed using novel technology give rise to a final product – a soluble, highly viscous functional fiber. 相似文献130.
This paper analyzes a Newsvendor type inventory model in which a manufacturer sells a single product to a retailer store whose
inventory is subject to errors stemming from execution problems. Hence, within the store, all of the products are not available
on shelf for sales either because the replenishment of the shelf from the backroom is subject to execution errors that mainly
result in products lost in the backroom or products misplaced on the other shelves of the store. We compare two situations:
in the first situation, the two supply chain actors are aware of errors and optimize their ordering decisions by taking into
account this issue. The second situation deals with the case where an advanced automatic identification system such as the
Radio Frequency Identification technology is deployed in order to eliminate errors. Each situation is developed for three
scenarios: in the centralized scenario, we consider a single decision-maker who is concerned with maximizing the entire supply
chain’s profit; in the decentralized uncoordinated scenario, the retailer and the manufacturer act as different parties and
do not cooperate. The third scenario is the decentralized coordinated scenario where we give conditions for coordinating the
channel by designing a buyback contract.
The authors would like to thank the editor, Prof. Dr. Hans-Otto Guenther, and two anonymous referees for their constructive
comments to improve this article. 相似文献