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71.
European river basin authorities are responsible for the implementation of the new river basin management plans in accordance with the European Water Framework Directive. This paper presents a new methodology framework and approach to define and evaluate environmental flow regimes in the realistic complexities that exist with multiple water resource needs at a basin scale. This approach links river basin simulation models and habitat time series analysis to generate ranges of environmental flows (e‐flows), which are evaluated by using habitat, hydropower production and reliability of water supply criteria to produce best possible alternatives. With the use of these tools, the effects of the proposed e‐flows have been assessed to help in the consultation process. The possible effects analysed are impacts on water supply reliability, hydropower production and aquatic habitat. After public agreements, a heuristic optimization process was applied to maximize e‐flows and habitat indicators, while maintaining a legal level of reliability for water resource demands. The final optimal e‐flows were considered for the river basin management plans of the Duero river basin. This paper demonstrates the importance of considering quantitative hydrologic and ecological aspects of e‐flows at the basin scale in addressing complex water resource systems. This approach merges standard methods such as physical habitat simulations and time series analyses for evaluating alternatives, with recent methods to simulate and optimize water management alternatives in river networks. It can be integrated with or used to complement other frameworks for e‐flow assessments such as the In‐stream Flow Incremental Methodology and Ecological Limits of Hydrologic Alteration. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
72.
We propose an approach to shape detection of highly deformable shapes in images via manifold learning with regression. Our method does not require shape key points be defined at high contrast image regions, nor do we need an initial estimate of the shape. We only require sufficient representative training data and a rough initial estimate of the object position and scale. We demonstrate the method for face shape learning, and provide a comparison to nonlinear Active Appearance Model. Our method is extremely accurate, to nearly pixel precision and is capable of accurately detecting the shape of faces undergoing extreme expression changes. The technique is robust to occlusions such as glasses and gives reasonable results for extremely degraded image resolutions. 相似文献
73.
A. Lopez I. Garces M.A. Losada J.J. Martinez A. Villafranca J.A. Lazaro 《Photonics Technology Letters, IEEE》2006,18(16):1696-1698
In this work, an intensity modulation/frequency-shift keying (IM/FSK) orthogonal modulation scheme is achieved by direct modulation of a distributed feedback laser source using its adiabatic chirp characteristics. Optical frequencies for "1" and "0" bits are separated only 0.7 GHz, obtaining a narrow-FSK modulation and, accordingly, a low residual intensity modulation. Ethernet frames at 1.25 Gb/s (GbE) are transmitted with a label inserted using coded mark inversion codification at a 155-Mb/s rate. Error rates for the Ethernet payload and for the label have been measured for different payload extinction ratios, showing the viability of this scheme for distances up to 25 km. 相似文献
74.
B. Dagens A. Martinez J.-G. Provost D. Make O. Le Gouezigou L. Ferlazzo K. Merghem A. Lemaitre A. Ramdane B. Thedrez 《Photonics Technology Letters, IEEE》2006,18(4):589-591
For the first time with a directly modulated InAs-GaAs quantum-dot laser, high extinction ratio (up to 17 dB) and 25/spl deg/C-85/spl deg/C single-mode-fiber data floor-free transmissions are achieved at 2.5 Gb/s. Moreover, an interferometric technique showed a nearly constant Henry factor /spl sim/2 until a bias current six times the threshold current. 相似文献
75.
S. A. Martinez M. P. Blodgett S. Sathish S. Mall 《Metallurgical and Materials Transactions A》2005,36(12):3385-3396
The evolution of fretting fatigue damage was investigated in shot-peened Ti-6Al-4V samples, by measuring the changes in the
surface residual stress, using the X-ray diffraction technique. The surface residual stress was found to relax as the number
of fretting fatigue cycles increased. The relaxation behavior of the residual stress with the increasing number of fretting
fatigue cycles was observed to occur in three stages. In the first 20 pct of the fretting fatigue life, a drastic relaxation
was observed. In the second part (between 20 and 70 pct), a gradually increasing behavior was observed. During the last 20
to 30 pct of the fretting fatigue life, a dramatic relaxation of the residual stress was found to occur. A complete relaxation
of the residual stress occurred in the fracture region. A scanning electron microscope observation of the microstructure of
the damaged region was used to examine the mechanisms leading to the relaxation of the residual stress. The development of
delaminations at the early stages of the accumulation of the fretting fatigue damage was observed to be the main cause of
the initial relaxation. The generation of microcracks from the voids left behind by the delaminations is responsible for the
additional relaxation of the residual stress. The coalescence of the microcracks generated from different delaminated regions
produced yet more relaxation of residual stress and, ultimately, the final fracture of the specimen. 相似文献
76.
B. Calvo M. A. Martinez M. Doblar 《International journal for numerical methods in engineering》2005,62(2):159-185
In this paper, an extension of the natural element method (NEM) is presented to solve finite deformation problems. Since NEM is a meshless method, its implementation does not require an explicit connectivity definition. Consequently, it is quite adequate to simulate large strain problems with important mesh distortions, reducing the need for remeshing and projection of results (extremely important in three‐dimensional problems). NEM has important advantages over other meshless methods, such as the interpolant character of its shape functions and the ability of exactly reproducing essential boundary conditions along convex boundaries. The α‐NEM extension generalizes this behaviour to non‐convex boundaries. A total Lagrangian formulation has been employed to solve different problems with large strains, considering hyperelastic behaviour. Several examples are presented in two and three dimensions, comparing the results with the ones of the finite element method. NEM performs better showing its important capabilities in this kind of applications. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
77.
Nonlinear blind source separation using kernels 总被引:13,自引:0,他引:13
We derive a new method for solving nonlinear blind source separation (BSS) problems by exploiting second-order statistics in a kernel induced feature space. This paper extends a new and efficient closed-form linear algorithm to the nonlinear domain using the kernel trick originally applied in support vector machines (SVMs). This technique could likewise be applied to other linear covariance-based source separation algorithms. Experiments on realistic nonlinear mixtures of speech signals, gas multisensor data, and visual disparity data illustrate the applicability of our approach. 相似文献
78.
Hassan H. Martinez J.-M. Dominguez C. Perles A. Albaladejo J. 《Education, IEEE Transactions on》2004,47(4):446-452
An innovative educational methodology adapted to the requirements of a new era with new societal and industrial challenges for electronic engineers is proposed in this paper. This active methodology, known as the Educational Innovation Project (EIP), is being studied in the Electronic Engineering (EE) degree of the Higher Technical School of Design Engineering at the Polytechnic University of Valencia, Valencia, Spain. The main objective of the EIP methodology is to improve the process of teaching and learning in order to increase student success. To accomplish this objective, the EIP method addresses various issues. From an organizational viewpoint, different structural aspects of the EE degree have been adapted, such as balancing and integrating lectures and laboratory sessions, advancing into interdisciplinary studies coordinated among all the subjects of the course, and strengthening the work in teams to tackle real engineer problems. The industrial computer engineering (ICE) subject is taken as a reference to show how these aspects have been applied. Regarding the faculty, lecturers participate in an open and permanent process of further training; attitudes toward cooperation and exchanges of experience among them are promoted; and research and reflection on new methodologies is encouraged. One of the challenges of the implementation of the EIP project is the development of multidisciplinary projects by team workers. The knowledge acquired from all the subjects is put into practice through the development of a common project to undertake real engineering problems. 相似文献
79.
This paper presents the results of the OEPM (Spanish Patent and Trademark Office)/OECD (Organisation for Economic Co-operation and Development) survey on the economic and financial uses of patents carried out in 2008 among Spanish business applicants of OEPM patents. It also summarizes evidence from previous surveys. All available information indicates that only a few Spanish firms holding patents license them out. Results from the OEPM/OECD survey also reveal that obtaining public support is the first financial use of patents for Spanish firms. Responses to the same OECD questionnaire by EPO patent applicants from several European countries are quite different: licensing out is an extended practice among EPO patent holders from different countries, including Spain, and convincing venture capitalists and private investors are their two most important financial uses of patents. In our view this suggests that there are significant differences across European countries as regards the development of national technology markets and results from international surveys are driven by responses from the largest and more developed countries. The drivers and actors in markets for patents that only protect inventions nationally may be quite distinct from those in markets for patents that protect inventions regionally, such as EPO patents within Europe. 相似文献
80.
Nowadays, many of the plastic components are aesthetic pieces, and they are fabric, thermoplastic vulcanizates (TPVs), or film coated. In the case of upholstered pieces, they are injected onto a textile tissue introduced into the mold, and they are finished with an edging process. Simulation programs used to optimize the injection process are not able to simulate the injection over fabrics, and therefore, it is difficult to select an injection machine without knowing the pressure drop inside the mold and without knowing how the parameters affect to the injection cycle or to the aesthetic aspect of this kind of pieces. This article presents a software for rapid calculations during the filling phase without the need for complex modeling. The program will be able to calculate pressure drop and other flow parameters that are fundamental for a good design of an industrial mold used in in‐mold decoration (IMD) technique. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers 相似文献