Influence of trimming of resistive thick films on nonlinearity of their current vs. voltage characteristics

Investigation of changes of nonlinearity of thick resistive films, trimmed by laser and by grinding, has been carried out. Laser trimming has been realized by an Ar laser, mechanical trimming by grinding of the layer by a milling machine using a diamond miller. The simplest method of trimming has been used - the resistors have been trimmed by realization of a groove, approximately in the middle of their length, perpendicularly to the axes of the resistors. The length of the trimming groove has been from 10% to 80% of the width of the resistor. All measured values of nonlinearity after trimming have been recalculated for starting values of the resistors. Nonlinearity has been examined for constant current density at the narrowest cross section of the resistive layer. It has been found that changes of nonlinearity caused by trimming depend on the ratio of the width and the length of the resistors. The changes have been very similar for resistors trimmed by the laser and for resistors trimmed mechanically

Testing of Normality of Data Files for Application of SPC Tools

Different types of statistical tests have been used for evaluation of the normality of selected data files. The files have been simulated to be on the border of normality. The results of the tests have been compared. It has been found that some files have been, using some type of a test, marked as normal, but using another type of a test, marked as non-normal. It is possible to find similar results by normality testing of data files obtained from production. Therefore, complementary tools for assessment of normality of the files under test have to be used. This paper compares results of normality testing of some simulated files by three basic tests of normality: test of elective skewness and kurtosis, Anderson-Darling test, and Kolmogorov-Smirnov test. It gives also directions indicating which other tools of exploratory analysis have to be used for verification of results obtained by different tests of normality

Influence of Carbon Nanotubes Added to a Commercial Adhesive

This paper describes the influence of carbon nanotubes onto electrical properties of electrically conductive adhesives. This work is related to our previous research that described electrical connection network within electrically conductive adhesive and possible advantages of non-spherical particles distributed within the adhesive matrix. Two different commercial conductive adhesives were used in this experiment and different amounts of carbon nanotubes were mixed using different methods (ultrasound/rotation/spatula mixing) into the matrix. The positive effect in terms of mechanical properties can be expected according to previous research in the material field. The goal of this work is to describe the influence of this additional filler onto electrical parameters and generally to improve the adhesive properties

Software design of optimization laboratory OptiLab

An overview of the software design, methods and data abstraction of the OptiLab framework is presented. The framework is aimed at the advanced analysis and optimization of mathematical models of physical fields and also coupled problems. The algorithms of the framework are implemented with respect to solution demands and huge data requirements. The paper presents a short description of the framework, its basic concept and structure

On Efficiency of ARQ and HARQ Entities Interaction in WiMAX Networks

Space scienc

Induction heating of rotating nonmagnetic billet in magnetic field produced by high-parameter permanent magnets

An advanced way of induction heating of nonmagnetic billets is discussed and modeled. The billet rotates in a stationary magnetic field produced by unmoving high-parameter permanent magnets fixed on magnetic circuit of an appropriate shape. The mathematical model of the problem consisting of two coupled partial differential equations is solved numerically, in the monolithic formulation. Computations are carried out using our own code Agros2D based on a fully adaptive higher-order finite element method. The most important resultsare verified experimentally on our own laboratory device

Evaluation of efficiency of technologies for wastewater sludge hygienisation

The paper compares the methods of hygienisation of wastewater treatment plants sludges with respect to meet legislative requirements of conditions for using the treated sludge on agricultural land. The paper draws a comparison of the experimental results between the method of hygienisation and stabilisation of the sludge through the autothermic aerobic thermophilic stabilisation (AATS) by pure oxygen and the method of sludge hygienisation by pasteurization. Results of the experiment confirm that sewage sludge treated by both assessed hygienisation technologies meets legislation requirements for application to agricultural soil.O

Postoj společnosti ke střelným zbraním v ČR

Firearms are a topic of today's society in many countries, and the Czech Republic is no exception. It is still a controversial topic, but it is becoming more and more relevant for all age groups, as we encounter firearms much more than in the past due to the internet, media, computer games, movies, and other aspects of today's world. Almost everyone has access to each of these possibilities at any time. The relevance and idea of firearms are also shaped by the situation in Ukraine, which has shaken the world. Firearms have been associated with society for a long time and have created a history in which they work together. Like many other things, firearms can be to our advantage, but they can also harm us as a society or as individuals. It is up to each individual to make a picture and boundary that they perceive as acceptable. The Czech Republic has a rich history of firearms, both in the early Middle Ages and in modern times, in which it also produces world-renowned models, and this can also influence society's perception of firearms. This work will focus on the historical development of society's view on the issue of firearms and their use, as well as on the modern view of this topic. Part of it is also a comparison of legislation regarding firearms in selected countries and a more detailed description of the legislation in the Czech Republic. The research to map the situation in the Czech Republic then focuses on the general public, including people of different age groups, which also includes the views of shooters, hunters, firearm owners, and even ordinary people who each have their own vision of this issue. The research will use a questionnaire with simple rating questions to provide a clear mapping of opinions

Possibilities of surface treatment of stainleess steels

Struktura korozivzdorných ocelí, technologie povrchových úprav, chemické úpravy austenitických ocelí, úpravy v radiofrekvenčním plazmatu.Structura of stainless steels, surface treatment technology, chemical treatment of austenitic steel, treatment in radiofrequency.