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Artificial locomotion control: from human to robots

ROBOTICS AND AUTONOMOUS SYSTEMS 2004年第4期47卷 203-223页

作者： Azevedo, C Poignet, P Espiau, B CNRS DPA P3M F-13402 Marseille 20 France LIRMM F-34392 Montpellier 05 France INRIA Rhone Alpes F-38334 Saint Ismier France

This paper concerns the simultaneous synthesis and control of walking gaits for biped robots. The goal is to propose an adaptable and reactive control law for two-legged machines. The problem is addressed with human locomotion as a reference. The starting point of our work is an analysis of human walking from descriptive (biomechanics) as well as explicative (neuroscience and physiology) points of view, the objective being to stress the relevant elements for the approach of robot control. The adopted principles are then: no joint trajectory tracking;explicit distinction and integration of postural and walking control;use of evolutive optimization objectives;on-line event handling and environment adaptation and anticipation. This leads to the synthesis of an original control scheme based on non-linear model predictive control: Trajectory Free NMPC. The movement is specified implicitly through coherent physical inequality constraints. Dynamic model and internal limitations of the system are part of the problem constraints. This work is validated by simulation results obtained for the Bip and Rabbit biped robots in various walking and standing situations and compared to human data recorded in these same situations. (C) 2004 Elsevier B.V. All rights reserved.

关键词： biped robots non-linear model predictive control optimization under constraints artificial walking TF-NMPC

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optimization of the direct Carnot cycle

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APPLIED THERMAL ENGINEERING 2007年第5-6期27卷 829-839页

作者： Feidt, M. Costea, M. Petre, C. Petrescu, S. Univ Politehn Bucuresti Fac Mech Engn Dept Appl Thermodynam Bucharest 060042 Romania Univ Nancy 1 CNRS URM 7563 LEMTA F-54504 Vandoeuvre Les Nancy France Bucknell Univ Dept Engn Mech Lewisburg PA 17837 USA

A model for the study and optimization of two heat reservoirs thermal machines is presented. The mathematical model basically consists of the First and Second Laws of Thermodynamics applied to the cycle and entire system, and the heat transfer equations at the source and sink. The internal and external irreversibilities of the cycle are considered by taking into account the entropy generation terms. Several constraints imposed to the system composed by the engine and the two heat reservoirs (namely, engine efficiency, or power output, or heat flux received by the engine, each of them together with imposed internal entropy generation and total number of heat transfer units of the machine heat exchangers) allow us to find the optimum operational conditions, as well as the limited variation ranges for the system parameters. Emphasis is put on coupling between various possible objective functions, namely thermal cost, useful effect, first law efficiency and whole system dissipation. It is for the first time to our knowledge when it has been proved that if one of the possible objective functions is fixed (as a parameter with imposed value), the optima of the other three always correspond to each other for the corresponding stationary state system, with a given optimum heat conductance allocation (one degree of freedom). Other interesting results are also reported in this paper. Some sensitivity studies were developed, too, with respect to various parameters of the model (engine performance, internal entropy generation, total number of heat transfer units). (c) 2006 Elsevier Ltd. All rights reserved.

关键词： optimization under constraints thermal engines non-linear heat transfer laws Carnot direct cycle

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Coding rules for amino acids in the genetic code: The genetic code is a minimal code of mutational deterioration

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ORIGINS OF LIFE AND EVOLUTION OF THE BIOSPHERE 2002年第1期32卷 23-33页

作者： Luo, LF Li, XQ Inner Mongolia Univ Dept Phys Hohhot Peoples R China

Coding rules for amino acids in the genetic code are discussed from the point that the genetic code is a minimal code of mutational deterioration. The global mutational deterioration (GMD) function is defined through several parameters describing single base mutations and amino acid distances. The problem of searching for the global minimum of the GMD function is discussed in some detail. From GMD minimization under initial constraints we have succeeded in deducing the standard genetic code.

关键词： amino acid distance coding rule globalmutational deterioration standard genetic code optimization under constraints single base mutation

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Towards Robust and Secure Watermarking 10

Towards Robust and Secure Watermarking

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12th ACM Multimedia Security Workshop

作者： Xie, Fuchun Furon, Teddy Fontaine, Caroline INRIA Rennes Bretagne Atlantique Res Ctr F-35042 Rennes France

ISBN: (纸本)9781450302869

This paper presents yet another attempt towards robust and secure watermarking. Some recent works have looked at this issue first designing new watermarking schemes with a security oriented point of view, and then evaluating their robustness compared to state-of-the-art but unsecure techniques. Our approach is, on contrary, to start from a very robust watermarking technique and to propose changes in order to strengthen its security levels. These changes include the introduction of a security criterion, an embedding process implemented as a maximization of a robustness metric under the perceptual and the security constraints, and a watermarking detection seen as a. contrario decision test. Our experimentations lead to, once again, a. trade-off between security and robustness. The technique is now perfectly secure against attacks mounted during the second edition of the BOWS challenge, but the price to pay is either a, lower robustness against common image processing, either a bigger probability of false alarm.

关键词： Watermarking robustness security attacks optimization under constraints

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Toward a new face recognition approach using OptimLBP and Learning Classifiers 9

Toward a new face recognition approach using OptimLBP and Le...

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9th International Conference on Wireless Networks and Mobile Communications (WINCOM)

作者： Dahmouni, Abdellatif Abdelouahad, Abdelkaher Ait Silkan, Hassan Univ Chouaib Doukkali Fac Sci Comp Sci Dept LAROSERI Lab El Jadida Morocco

ISBN: (数字)9781665452762

ISBN: (纸本)9781665452762

Face recognition has become a popular biometric technology to fight crime, prevent fraud, and provide security of various human-system interactions. For this reason, researchers have developed several face recognition approaches to minimize the impact of the human factor. In this paper, Optimal Local Binary Pattern (Optim-LBP) features extraction was used to improve face description and preserve features of crucial face components. Afterwards, the 2D Linear Discriminant Analysis (2DLDA) subspace method was used to generate reduced and discriminated face features data and the SVMs Classifiers to perform the classification process. Finally, the effectiveness of the proposed approach was evaluated using the ORL, Yale, and AR face's databases.

关键词： LBP Optim-LBP Entropy optimization under constraints 2DLDA SVM and Machine Learning

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CONSTRAINED BUNDLE ADJUSTMENT APPLIED TO WING 3D RECONSTRUCTION WITH MECHANICAL LIMITATIONS

CONSTRAINED BUNDLE ADJUSTMENT APPLIED TO WING 3D RECONSTRUCT...

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IEEE International Conference on Image Processing (ICIP)

作者： Demoulin, Quentin Lefebvre-Albaret, Francois Basarab, Adrian Kouame, Denis Tourneret, Jean-Yves Airbus 316 Route Bayonne F-31060 Toulouse France Univ Toulouse IRIT ENSEEIHT Tesa F-31071 Toulouse France Univ Toulouse CNRS Univ Paul Sabatier IRIT UMR CNRS 5505 Toulouse France

ISBN: (纸本)9781728163956

Aircraft certification procedures require the estimation of wing deformation, which is a very challenging problem in photogrammetry applications. Indeed, in real flight conditions with varying environment, 3D reconstruction is strongly degraded. To cope with this issue, we propose to introduce prior knowledge about the wing mechanical limits in the photogrammetry reconstruction method. These mechanical limits are expressed as appropriate regularizations that are included into the classical bundle adjustment step. The proposed approach is evaluated using data acquired on a real aircraft yielding promising results.

关键词： Bundle adjustment optimization under constraints wing deformations mechanical limits

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Design Methodology with optimization of an Interleaved Buck Converter for Automotive Application

Design Methodology with Optimization of an Interleaved Buck ...

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IEEE EUROCON Conference

作者： Bendali, M. Larouci, C. Azib, T. Marchand, C. Coquery, G. ESTACA Lab Commande & Syst 34-36 Rue Victor Hugo F-92300 Levallois Perret France CNRS UMR 8507 SUPELEC UPMC LGEP SPEE Labs UPS11 Paris France IFSTTAR Paris France

ISBN: (纸本)9781467322324;9781467322300

This paper presents a design methodology applied to interleaved converters. This methodology is based on a multi-physic optimisation. The number of cells is used as a key parameter to formalise this approach with analytical models established to offer compromise needed between the computation time and results accuracy. The proposed methodology is applied to an interleaved buck converter for automotive application considering electric, volume, efficiency and thermal constraints. It allows to find the optimal converter architecture by searching the optimal number of cells and adequate active and passive components selected from a manufacturer data base. The methodology is drawn up to remove the risk of feasibility of a converter configuration considering several design specifications.

关键词： interleaved power converters optimization under constraints multi-physic modeling

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Hierarchical Constrained Bayesian optimization for Feature, Acoustic Model and Decoder Parameter optimization 18

Hierarchical Constrained Bayesian Optimization for Feature, ...

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18th Annual Conference of the International-Speech-Communication-Association (INTERSPEECH 2017)

作者： Chandrashekaran, Akshay Lane, Ian Carnegie Mellon Univ Dept Elect & Comp Engn Pittsburgh PA 15213 USA

ISBN: (纸本)9781510848764

We describe the implementation of a hierarchical constrained Bayesian optimization algorithm and it's application to joint optimization of features, acoustic model structure and decoding parameters for deep neural network (DNN)-based large vocabulary continuous speech recognition (LVCSR) systems. Within our hierarchical optimization method we perform constrained Bayesian optimization jointly of feature hyper-parameters and acoustic model structure in the first-level, and then perform an iteration of constrained Bayesian optimization for the decoder hyper-parameters in the second. We show the the proposed hierarchical optimization method can generate a model with higher performance than a manually optimized system on a server platform. Furthermore, we demonstrate that the proposed framework can be used to automatically build real-time speech recognition systems for graphics processing unit (GPU)-enabled embedded platforms that retain similar accuracy to a server platform, while running with constrained computing resources.

关键词： Hyper-Parameter optimization Bayesian optimization Deep Neural Networks Speech Recognition optimization under constraints

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optimization of Diagnostics with Respect to the Diagnostic Coverage and the Cost Function

Optimization of Diagnostics with Respect to the Diagnostic C...

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24th International Conference on Information, Communication and Automation Technologies (ICAT)

作者： Wacker, H. D. Holub, P. Boercsoek, J. Univ Kassel D-34125 Kassel Germany

ISBN: (纸本)9781479904310

In this paper the authors study a Safety Instrumented System (SIS) subjected to periodically performed diagnostic measures or tests. They focus their interest onto partial tests similar to partial stroke tests, which are well known from testing valves. They then introduce diagnostic parameters in order to quantify manual, automatic and semi-automatic testing mathematically, and they distinguish between two different diagnostic modes: The semi-automatic component-based mode and the semi-automatic-time-based mode. In Chapter V, they investigate the semi-automatic mode by means of two functions depending on their diagnostic parameters: The diagnostic coverage factor and the cost function. They then pose two optimization problems in form of two linear programs. The first one minimizes the cost function under constraints on the diagnostic coverage, and the second one maximizes the diagnostic coverage under constraints on the cost function. The paper closes with the examples of a 1oo1-system and a 2oo2-system.

关键词： diagnostics proof test partial stroke test failure rate diagnostic coverage factor mean time to failure probability of failure on demand automatic diagnostics manual diagnostics semi automatic diagnostic linear programming optimization under constraints cost function cost factor 1oo1-system

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Contribution of the land use allocation model for agroecosystems: The case of Torrecchia Vecchia

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JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019年 252卷 109607-000页

作者： Elalamy, Yanis Doyen, Luc Mouysset, Lauriane Univ Bordeaux GREthA Ave Leon Duguit Pessac France Leonardo Rue Lamartine Paris France CIRED 45 Bis Ave Belle Gabrielle F-94130 Nogent Sur Marne France

In this study, we developed a bio-economic model coupling land use and ecosystem services to investigate the role of forests on a broad set of ecosystem services, including carbon sequestration, soil quality and biodiversity. As a case study, the model was calibrated with economic, agronomic and ecological data from the Torrecchia Vecchia agroecosystem in Italy. In our analysis of optimal land use allocation, the results showed that diversified land use is required to provide a good balance between provisioning and non-provisioning ecosystem services. More specifically, the development of woodlands alongside farming activities had a positive impact on the soil quality score and on landscape heterogeneity, which is a proxy for ecosystem function and resilience. These findings demonstrate that the inclusion of woodlands can alleviate the trade-offs between provisioning and non-provisioning services as they can generate profit while allowing for better soil quality and biodiversity relative to more intensive land use. The study also confirms that a landscape-scale method can be used to investigate agroecosystem management problems when spatially explicit data is not available.

关键词： optimization under constraints Viability Land use Ecosystem services Tipping points

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