Constraint propagation on quadratic constraints

This paper considers constraint propagation methods for continuous constraint satisfaction problems consisting of linear and quadratic constraints. All methods can be applied after suitable preprocessing to arbitrary algebraic constraints. The basic new techniques consist in eliminating bilinear entries from a quadratic constraint, and solving the resulting separable quadratic constraints by means of a sequence of univariate quadratic problems. Care is taken to ensure that all methods correctly account for rounding errors in the computations. Various tests and examples illustrate the advantage of the presented method.     

基于∑-△转换器并集成了电流和温度传感功能的IGBT模块

市场的需求推动了系统集成在功率电子行业中的发展。本文将IGBT模块集成精确的电阻取样(如英飞凌MIPAQ^TM系列)与IGBT片上电流检测功能进行比较。同时对通过采用DBC上集成的NTC热敏电阻测量方法和通过IGBT片上集成的温度检测二极管测量方法进行了比较。接下来,在模块内部还采用∑-△转换器和无磁芯变压器技术对取样的信号进行转换和隔离传输。     

Stability and performance analysis of a SiC-based cascode switch and an alternative solution

Wide band-gap semiconductors are most attractive as materials for power devices due to low losses, improved temperature capability and high thermal conductivity. Although silicon carbide Schottky diodes have been commercially available on the market for years, an active wide band-gap switch is still missing. Probably the best performance of upcoming devices is gained with normally-on concepts such as silicon-carbide JFETs and gallium-nitride HEMTs. However, the vast majority of power electronic topologies rely on normally-off switches. An alternative approach is the use of the cascode concept which combines a normally-on wide band-gap device with high blocking capability and a low-voltage normally-off silicon MOSFET. In this work, the performance and stability of such an arrangement is analyzed and an alternative solution is proposed.     

Inverted-U Function Between Salivary Cortisol and Retrieval of Verbal Memory After Hydrocortisone Treatment.

The present study investigated the effect of a single oral dose of hydrocortisone (cortisol) on retrieval of verbal and nonverbal declarative memory. Fifty-nine healthy participants were randomly assigned to either receive 25 mg cortisol or a placebo 45 min before retrieval in a standardized memory test procedure. There was no global effect of cortisol on either verbal or nonverbal memory. However, a specific negative effect on free recall of associative verbal material appeared. In addition, high responders (salivary cortisol concentration > 68.25 nmol/L) exhibited impaired verbal memory compared with low responders (     

The optimization test environment

The Optimization Test Environment is an interface to efficiently test different optimization solvers. It is designed as a tool for both developers of solver software and practitioners who just look for the best solver for their specific problem class. It enables users to:

Choose and compare diverse solver routines;

Organize and solve large test problem sets;

Select interactively subsets of test problem sets;

Perform a statistical analysis of the results, automatically produced as , PDF, and JPG output.

The Optimization Test Environment is free to use for research purposes.