An edge problem having no singularity at the corner

The problem of thermal stresses induced by a uniform temperature rise in a rectangular plate clamped along an edge is formulated as a variational problem with a subsidiary condition. It is demonstrated that the solution in the clamped corner is known a priori and is non-singular. An approximate state of stress through the plate is obtained by the method of Kantorovich. It is shown that the finite element method fails to solve this problem. It is also shown that a previous investigation of this problem suffers from serious drawbacks.     

Cytochrome P450 3A4 activity in premenopausal and postmenopausal women, based on 6-beta-hydroxycortisol:cortisol ratios

STUDY OBJECTIVE: To characterize cytochrome P450 (CYP) 3A4 activity in premenopausal and postmenopausal women by evaluating the urinary 6-beta-hydroxycortisol:cortisol ratio. DESIGN: Prospective study SUBJECTS: Thirteen premenopausal and 13 postmenopausal women who were healthy and not receiving drugs known to affect CYP3A4 activity INTERVENTIONS: Beginning on day 2 of menses, premenopausal women collected first morning urine samples every other day for a complete menstrual cycle. Postmenopausal women collected first morning urine every other day for 28 days. MEASUREMENTS AND MAIN RESULTS: Mean weekly 6-beta-hydroxycortisol:cortisol ratios did not differ during the phase (week) of the menstrual cycle. Daily ratios did not differ in postmenopausal women. No difference between premenopausal and postmenopausal women was found on comparing overall median ratios. CONCLUSION: Cytochrome P450 3A4 activity as measured by 6-beta-hydroxy cortisol:cortisol ratio did not differ by week of menstrual cycle, suggesting no menstrual cycle-related changes. Menopause does not appear to be associated with differences in CYP3A4 activity, compared with premenopause.     

HTGR experience, programs, and future applications

This paper reviews the current status of the programs for the development of high-temperature gas-cooled reactors (HTGRs) in the major industrial countries of the world. Existing demonstration plants and facilities are briefly described, and national programs for exploiting the unique high-temperature capabilities of the HTGR for commercial production of electricity and in process steam/heat applications are discussed.     

Deformation Features of the Propagation of Cleavage Cracks in a Ferritic-Pearlite Microstructure in the Ductile to Brittle Transition Interval

Inorganic Materials - In the paper, the deformation features of the propagation of cleavage cracks in low-alloy low-carbon steel with a ferritic-pearlite microstructure by example of steel 09G2S...     

Computer Modelling of Deformation of Steel Samples with Mushy Zone

The integrated casting and rolling of steel plates in processes such as Inline Strip Production or Arvedi Steel Technology is the latest and very efficient way of hot strip production. The numerical modelling is very helpful in developing a “know how” theory for the mentioned processes. One of the most important relationships having crucial influence on the metal flow path is the strain‐stress curve. The inverse method, which is usually the only method of calculating a real strain‐stress relationship, needs a good mathematical model describing the plastic behaviour of the material. The model presented in the current paper fills the gap in modelling of plastic deformation of semi‐solid materials. On the other hand, the mathematical modelling should be closely related to experiments. The well known machine allowing tests in the discussed temperature range is the GLEEBLE thermo‐mechanical simulator. However, carrying out experiments with steel deformation in the semi‐solid state using this machine is very expensive. Therefore, application of a dedicated computer simulation system is strictly required. Inverse analysis and appropriate modelling of the testing procedure makes tests possible, first of all, but it also results in lowering testing cost. The newest version of the Def_Semi_Solid is a unique FEM system supporting tests at extra high temperature.     

Stability of a laser cavity with a two-mirror multipass system

An investigation is made of the stability of a laser cavity in which one of the nontransmitting mirrors is a multipass system consisting of two spherical mirrors. The stability of the cavity depends strongly on the number of passes of the beam in the multipass system, the configuration of the mirrors, and the constriction of the beam entering the system. A stable cavity configuration ensures low diffraction losses in the system and efficient lasing. Pis’ma Zh. Tekh. Fiz. 25, 33–38 (November 12, 1999)     

Application of generalized dynamic neural networks to biomedical data

This paper reviews the application of continuous recurrent neural networks with time-varying weights to pattern recognition tasks in medicine. A general learning algorithm based on Pontryagin's maximum principle is recapitulated, and possibilities of improving the generalization capabilities of these networks are given. The effectiveness of the methods is demonstrated by three different real-world examples taken from the fields of anesthesiology, orthopedics, and radiology.     

Child parent relationship training: Parents' perceptions of process and outcome.

Child Parent Relationship Training (CPRT) is a play-based parent consultation model designed for children (ages 3–10) who may be struggling emotionally or behaviorally. CPRT aims to help parents develop empathy and appreciation for their children, increase parenting ability and confidence, and strengthen parent–child relationships. To date, the majority of CPRT studies have been quantitative in nature. There has been limited research on the effectiveness of CPRT using qualitative methodologies, but existing qualitative studies show promising results. The current study utilized an ethnographic approach to examine the acceptability and perceived effectiveness of CPRT. Findings indicated that the parents perceived the CPRT model to be both acceptable and effective (e.g., increased knowledge and confidence in parenting, enhanced parent–child communication, strengthened parent–child relationships, and reduced behavioral problems among child participants). Limitations of the study and implications for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Methods of calculating leakage inductance of transformer windings

Precise and simple formulas for determining the area of the reduced leakage channel of concentric windings of equal heights in a transformer are suggested to replace formulas in which the approximate values of mean winding length are used to calculate the leakage inductance.