Stabilization of the inverted pendulum around its homoclinic orbit

The inverted pendulum has been used as a benchmark for motivating the study of nonlinear control techniques. We propose a simple controller for balancing the inverted pendulum and raise it to its upper equilibrium position while the cart displacement is brought to zero. The control strategy is based on an energy approach of the cart and pendulum system.     

INPI, the Internet and electronic commerce

The information society has always raised important social, economic and cultural issues for our country. In the early days, Minitel was a major factor in user awareness and education in France. Internet-based technologies then offered the ergonomics and user-friendliness expected by a wide section of the public, both French-speaking and otherwise. Our task of disseminating industrial property information, which is a public service, was therefore facilitated by the fact that access was quick and easy and was available anywhere in the world seven days a week and 24 h a day.I – The patents web www.inpi.fr/brevets and esp@cenet: In order to reach as many members of the public as possible and as part of the esp@cenet project, since September 1998 the patents web www.inpi.fr/brevets has been offering access in French to the past two years of FR, EP and PCT publications, the full text of FR applications and a link to esp@cenet.Although the request forms seem simple, not every Internet user understands what professionals like ourselves mean by publication number, priority, filing, inventors, applicants or IPC code.The patents web www.inpi.fr/brevets therefore offers an added-value service, namely the natural-language search engine CIB-LN (in English this would be IPC-NL).This extremely powerful engine enables all French-speaking Internet users to identify the relevant patent classification codes in French using their own words, and to search with the utmost efficiency on the Net using both the patents web www.inpi.fr/brevets and any other patents sites which accept IPC entries.This achievement is currently the subject of a study of the transferability of the natural language search engine into other languages.We are currently experiencing the fourth commercial and marketing revolution, in the shape of electronic commerce. The first revolution involved the emergence of fairs in the Middle Ages, the second the establishment of department stores in the late 19th century, and the third the introduction of volume retailing in the 1950s.Electronic commerce therefore poses a major challenge to any private or public company. Marketing estimates and forecasts indicate that information marketing services will be among the most successful. INPI certainly hopes to take up this challenge.II – INPI shop: Our shop, which is in the process of being set up, will combine information marketing services with:

• trade mark priority and French Commercial and Companies Register (RNCS) searches;

• copies of patents;

• strategic and competitor information search (RISC) services;

• historical background;

• BREF, COSMOS, GLOBALPAT and RXN CD-ROMs;

• official publications.

The success and viability of an Internet shop is directly proportional to its links to other shops or service sites. It is therefore quite obvious that the INPI shop will be linked to direct INPI search systems (the patents, trade marks and companies webs) and to any other search service or shop which would like to be linked to it.     

Temporal relation algebra for audiovisual content analysis

Multimedia Tools and Applications - The context of this work is to characterize the content and the structure of audiovisual documents by analysing the temporal relationships between basic events...     

Mathematical morphology on hypergraphs,application to similarity and positive kernel

The focus of this article is to develop mathematical morphology on hypergraphs. To this aim, we define lattice structures on hypergraphs on which we build mathematical morphology operators. We show some relations between these operators and the hypergraph structure, considering in particular transversals and duality notions. Then, as another contribution, we show how mathematical morphology can be used for classification or matching problems on data represented by hypergraphs: thanks to dilation operators, we define a similarity measure between hypergraphs, and we show that it is a kernel. A distance is finally introduced using this similarity notion.     

On the applicability of the Heliosat-2 method to assess surface solar irradiance in the Intertropical Convergence Zone,French Guiana

Measurements of daily means of surface solar irradiance made at four ground stations in French Guiana are compared to estimates from the HelioClim-3 database produced by the Heliosat-2 method applied to Meteosat satellite images. The bias ranges from 12 W m^?2 (6% of the mean of measurements) to 23 W m^?2 (12%), depending on the stations. The root mean square difference ranges between 23 W m^?2 (11%) and 35 W m^?2 (18%). The correlation coefficient (r) is close to 0.9. Better results are observed during the rainy season than during the dry season. Uncertainties are mainly due to the presence of clouds, large viewing angles of the Meteosat satellite, and limitations of the atmospheric transmittance model under the tropical atmospheric conditions. It is concluded that the Heliosat-2 method provides new knowledge about solar radiation in French Guiana.     

Youth gambling behaviors: An examination of the role of resilience.

The study of resilient children has overturned many deficit-focused models concerning the ontogenesis of children raised in adversity. This study explored the relationship between risk and protective factors, resilience, and youth gambling behavior. More specifically, this study examined the relative contribution of various risk and protective domains in relation to problem gambling behavior and examined whether youth identified as resilient (high risk exposure- high internalized protection) were as likely as those identified as vulnerable (high risk exposure-low internalized protection) to engage in excessive gambling behavior. The sample consisted of 1,273 students ages 12 to 19. The findings demonstrated that risk and protective factors each provide a unique contribution to the prediction model of gambling problems. Resilient and vulnerable youth differed significantly in their self-reported gambling severity. As well, resilient youth were not statistically distinguishable from low-risk exposure groups in terms of their gambling severity. Findings are interpreted with respect to resilience and prevention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neutron Scattering from the Flux Line Lattice in the Cubic (K, Ba)BiO 3 Superconductor

Small Angle Neutron Scattering has been used to observe diffraction from the flux line lattice in the fully isotropic (K, Ba)BiO ₃ high T _c superconductor. We show that the flux lines are ordered into a hexagonal lattice at low field (H < H _e 0.6T H _g (0) where H _g is the second order vortex glass transition field). The diffracted intensity continuously drops to zero as the field is increased towards H _e . Those observations are in good agreement with recent theoritical works which suggested that the formation of dislocations becomes favorable above H _e leading to a glassy structure. The field H _e lies close to the onset of the second peak in magnetization measurements indicating that this peak is related to the change in the vortex structure.     

Sturmian Trees

We consider Sturmian trees as a natural generalization of Sturmian words. A Sturmian tree is a tree having n+1 distinct subtrees of height n for each n. As for the case of words, Sturmian trees are irrational trees of minimal complexity.     

Measure of circularity for parts of digital boundaries and its fast computation

This paper focuses on the design of an effective method that computes the measure of circularity of a part of a digital boundary. An existing circularity measure of a set of discrete points, which is used in computational metrology, is extended to the case of parts of digital boundaries. From a single digital boundary, two sets of points are extracted so that the circularity measure computed from these sets is representative of the circularity of the digital boundary. Therefore, the computation consists of two steps. First, the inner and outer sets of points are extracted from the input part of a digital boundary using digital geometry tools. Next, the circularity measure of these sets is computed using classical tools of computational geometry. It is proved that the algorithm is linear in time in the case of convex parts thanks to the specificity of digital data, and is in O(nlogn) otherwise. Experiments done on synthetic and real images illustrate the interest of the properties of the circularity measure.     

Strain differences in the isolation-induced effects on prepulse inhibition of the acoustic startle response and on locomotor activity.

The authors investigated the effects of isolation rearing on acoustic startle response, prepulse inhibition (PPI), its modification by apomorphine, and locomotor activity in 3 rat strains: Wistar (WS), Sprague-Dawley (SD), and Lister hooded (ListH). SD and ListH, but not WS, showed isolation-induced PPI deficits. In 2 consecutive PPI tests, only SD isolates showed significant PPI deficits. An isolation rearing effect in ListH was significant only in the 1st PPI test. Apomorphine dose-dependently (0.0–0.5 mg/kg) disrupted PPI, but sensitivity to the drug differed, with WS and SD rats being more sensitive to lower doses (0.01–0.05 mg/kg) than ListH rats (0.5 mg/kg). Isolates, irrespective of strain, did not differ from grouped rats in their response to the apomorphine challenge. Only WS and ListH isolates demonstrated significantly increased locomotor activity. Strain differences in the different parameters measured did not predict isolation-induced effects on PPI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)