New Stainless Steel Solutions as Economic Alternatives to Classical 1.4301 Austenitic Grades

In the recent situation of a historically high nickel price, austenitic stainless steels, such as 1.4301, became too expensive compared to their actual technical value in many applications. This paper presents two new stainless steel grades developed by ArcelorMittal to replace 1.4301. The first one is a 20%Cr ferritic grade. The second one is a low‐Ni Cu‐bearing austenitic grade. The choices in the compositions are described as a function of the technical requirements, economical target and the production process limitations. The final properties are discussed as a function of the composition and compared with 1.4301 and other existing stainless steels. Finally, the complementarities of these two new grades are highlighted in regard to the different application markets considered.     

HERSCHEL—PACS Bolometer Arrays for Submillimeter Ground-Based Telescopes

The Herschel Space Observatory will carry onboard a new kind of bolometric architecture for the PACS (Photodetector Array Camera and Spectrometer) submillimeter photometer. These new generation CCD-like multiplexed bolometer arrays are buttable and enable the conception of large fully sampled focal planes either for space or for ground-based telescopes. We present here some development for ground-based applications in the context of the ARTEMIS (ARchitecture de bolomètres pour des TElescopes sub-MIllimétriques au Sol) project. We have developed an electro-thermal numerical model that simulates the performances of these semiconducting bolometers under specific ground-based conditions (different wavelengths and background powers for example). This model permits to determine the optimal parameters for each condition and shows that the bolometers can be background limited in each atmospheric transmission window between 200 and 450 microns. We also describe the optical system that provides a high optical efficiency in each submillimeter atmospheric window. Astronomical observations made with a prototype on the APEX telescope are presented.     

Natural ageing of tri-layer polyethylene film: Evolution of properties and lifetime in North Africa region

The effects of natural ageing in the north Algeria of tri-layer films lay down hot greenhouse made of low-density polyethylene are presented in this work. Ageing was monitored by observing the changes of physical, mechanical and structural effects on the various greenhouse faces. It has been shown that the structural change occur on the outside face of the films, while the inside faces are protected by the dye. The study shows that the measured parameters are directly related to the criteria of evaluation of the greenhouse effectiveness. The lifetime of these films under natural conditions in north Algerian was estimated to be 10 months.     

Online measurement of water content in candidate reference materials by acousto-optical tuneable filter near-infrared spectrometry (AOTF-NIR) using pork meat calibrants controlled by Karl Fischer titration

Certified reference materials (CRMs) are prepared from a wide variety of matrices. Water removal is an excellent way of achieving increased matrix lifetime and hence CRM stability. High-speed acousto-optical tuneable filter near-infrared spectrometry (AOTF-NIR) has been implemented for measurement of water content in powder matrix reference materials in amber glass vials. Almost 50,000 spectra were collected from 1300 to 2100 nm with a 2 nm increment for powders of meat, rye grass, potato, cotton seed and sugar beet. The AOTF-NIR instrument was placed in a capping machine, with a measurement frequency of 10–15 vials/min and a trigger signal for reproducible collection of spectra. The calibrants comprised 19 pork meat powder samples equilibrated with different hygrostatic solutions or subjected to oven drying to achieve different water concentrations. Mixtures of powders with different water content were also prepared in order to obtain a calibration range from 0.5 to 8.3% water (m/m). All calibration samples were measured by volumetric Karl Fischer titration (V-KFT), accredited under ISO 17025. The calibrants were then measured by AOTF-NIR together with the samples. Multiplicative scatter correction (MSC) was applied to the absorbance spectra in order to correct for the scattering of light in the different powders and scattering effects from the vials. A partial least squares regression model (PLS) based on two principal components was created and applied for prediction of water content in the samples with a standard error of 0.5% water (m/m).     

Use of analogies in therapeutic situations: An analogue study.

141 participants read vignettes that described stressors encountered by college students. Each vignettes also included information about the students' hobby and therapeutic advice the students might follow to deal with their stressors. This advice was expressed in either a literal or an analogical form. Ss were asked to read the vignettes from the perspective of a therapist, a patient, or an observer, and to rate the advice component of each vignette for helpfulness. Analogical advice was rated as significantly more helpful than literal advice on a variety of questions. A surprise cued-recall memory test showed that Ss in the analogical condition but not in the literal condition remembered information according to their assigned role. In the role of patients, Ss showed greatest recall for the therapeutic advice, but in the role of therapists, they showed greatest recall for the students' stressors. In line with a growing literature in cognitive psychology, these results show that the impact of analogies in therapeutic interactions is a combined is a combined function of the material to be processed and the role of the person processing it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Constraint-induced movement therapy: A new approach to treatment in physical rehabilitation.

Constraint-Induced (CI) Movement Therapy is a new approach to the rehabilitation of movement, based on research in neuroscience and behavioral psychology, that has been shown in controlled experiments to greatly increase the amount of use of an impaired upper extremity in chronic stroke patients in both the laboratory and the real world. CI Therapy consists of a family of techniques that induce stroke patients to greatly increase their use of an affected upper extremity for many hours a day over 10 to 14 consecutive days. The signature technique involves restricting the contralateral arm in a sling and training the affected arm. This commentary reviews the animal and human research and the theoretical formulation on which CI Therapy is based. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A generalized galerkin method for steady convection-diffusion problems with application to quadratic shape function elements

A generalization of the standard Galerkin finite element method is considered to enable it to deal successfully with steady convection-diffusion problems. The proposed method employs a generalized governing equation which is obtained by subtracting from the original differential equation the scalar product of its gradient by a vector of free parameters associated with each of the coordinate directions. The generalized equation is successively discretized by the standard Bubnov-Galerkin finite element method. The effectiveness of the method is illustrated for the case of quadratic local interpolations in one and two space dimensions.     

A recognition network model-based approach to dynamic image understanding

In this paper, we present definitions for a dynamic knowledge-based image understanding system. From a sequence of grey level images, the system produces a flow of image interpretations. We use a semantic network to represent the knowledge embodied in the system. Dynamic representation is achieved by ahypotheses network. This network is a graph in which nodes represent information and arcs relations. A control strategy performs a continuous update of this network. The originality of our work lies in the control strategy: it includes astructure tracking phase, using the representation structure obtained from previous images to reduce the computational complexity of understanding processes. We demonstrate that in our case the computational complexity, which is exponential if we only use a purely data-driven bottom-up scheme, is polynomial when using the hypotheses tracking mechanism. This is to say that gain improvement in computation time is a major reason for dynamic understanding. The proposed system is implemented; experimental results of road mark detection and tracking are given.