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Y Lööf

Publications and source records attributed to Y Lööf.

5 recordsLinked to original sources
PubMed1990

Improving electromyographic jitter measurements by analysis of the firing pattern.

A new model for predicting the jitter from the firing pattern is presented. The jitter is decomposed into two components: 1) variation explained by the firing pattern, 2) random variation. The first component reflects the velocity recovery function of the muscle fiber. The second component reflects the neuromuscular transmission. Two methods are deduced from the model. Method I predicts the jitter from the most recent discharge. Method II can take any period of firing pattern into consideration. Model parameters can be given a physiological interpretation. Measures describing the velocity recovery function are derived. An improved estimate of the neuromuscular jitter is obtained compared to traditional jitter measures under simulated conditions.

Computer Simulation↗
PubMedDate not supplied

An operator approach to interactive data processing. I. The system.

A computer software system for interactive data processing is described. Data are transferred between functions ('operators'). Execution flow is designed in a semi-graphical language. Data are composed of arbitrary data types in sequences of any length. The system works as an interpreter and the user may define or modify its current operation without delay. Lucidity is increased by the possibility of building complex functions ('macros') from simpler ones. Once such a construction has been made, the functions included can be made transparent to the user. Portability is emphasized by using only standard PASCAL. To promote flexibility, entirely new procedures and data types can be introduced. Both short- and long-term solutions are thus supported.

Electronic Data Processing↗
PubMedDate not supplied

An operator approach to interactive data processing. II. Some applications of scalars and vectors.

A modular software system for interactive data processing is described in part I of this series. Flexibility and portability are stressed. The system works as an interpreter and new functions may be introduced instantly. A simple graphical user interface controls performance. Arbitrary data types are supported. In the current work, the system has been implemented for numerical data (scalars and one-dimensional arrays). Some commonly used parametric and non-parametric statistical procedures (such as Students t-test, linear regression, Mann-Whitney and Wilcoxon tests) illustrate the use of scalars. Arrays can indicate complex quantities, used in signal analysis. The fast Fourier transform is a basic building block. It is included into other functions such as convolution, cross-correlation and digital filter design. The benefit of such constructions is illustrated by adaptive filtering of evoked potentials.

Computers↗