Rejected axioms for the “nonsense-logic” W and the k-valued logic of Sobociński

In this paper rejection systems for the “nonsense-logic” W and the k-valued implicational-negational sentential calculi of Sobociński are given. Considered systems consist of computable sets of rejected axioms and only one rejection rule: the rejection version of detachment rule

Refutation systems for a system of nonsense-logic

In the paper rejection systems for a system of nonsense-logic are investigated. The first rejection system consists of four rejected axioms and only one rejection rule the rule of rejection by detachment. The second one consists of one rejected axiom and two rejection rules: the rule of rejection by detachment and the rule of rejection by substitution. The aim of the paper is to present also a proof of Ł-decidability for the considered systems

On two different concepts of set

The article contains no abstrac

Ten parameter screening of the single point incremental forming process

There are many factors that influence the quality of parts formed by single point incremental forming. The purpose of this work is to take a Design of Experiments approach to study the effects of all major parameters on the quality of the formed part. The two quality measures used were the shape error and the surface roughness. Analysis of Means calculations were performed using these measures. An improvement in surface quality was observed for larger tool sizes and reductions in step size. This study also shows that the spindle direction during forming has a major role on the surface quality of formed parts

PROJECT PHANTOM: OPTIMIZING THE MISSING PERSON SEARCH PROCESS IN RUSSIA

Finding missing people is a big challenge for any country and Russia could benefit by improved search strategies. The goal of our project, sponsored by Russia-based Foton Bank, was to construct a detailed block diagram for a search protocol with sensitivity to time and to different types of missing persons (children, elderly, etc.) to be implemented in a mobile application. This application will expedite and streamline search operations for missing persons in Russia and will integrate the multiple services and networks of databases currently in place

On Stress-Induced Polarization Effect in Ammonothermally Grown GaN Crystals

The results of basic ammonothermal crystallization of gallium nitride are described. The material is mainly analyzed in terms of the formation of stress (called stress-induced polarization effect) and defects (threading dislocations) appearing due to a stress relaxation process. Gallium nitride grown in different positions of the crystallization zone is examined in cross-polarized light. Interfaces between native ammonothermal seeds and new-grown gallium nitride layers are investigated in ultraviolet light. The etch pit densities in the seeds and the layers is determined and compared. Based on the obtained results a model of stress and defect formation is presented. New solutions for improving the structural quality of basic ammonothermal gallium nitride crystals are proposed

Fundamental Studies on Crystallization and Reaching the Equilibrium Shape in Basic Ammonothermal Method: Growth on a Native Lenticular Seed

In this paper, a detailed investigation of the basic ammonothermal growth process of GaN is presented. By analyzing the crystallization on a native seed with a lenticular shape, thus with an intentionally varying off-cut, we wanted to answer some basic questions: (i) Which crystallographic planes play the most important role during growth (which planes are formed and which disappear)? (ii) What is the relationship between the growth rates in different crystallographic directions? (iii) What is the influence of the off-cut of the seed on the growth process? Two non-polar slices, namely, 12¯10 and 1¯100, as well as a 0001 basal plane slice of an ammonothermal crystal were analyzed. The examined planes were selectively etched in order to reveal the characteristic features of the growth process. The applied characterization methods included: optical microscopy with Nomarski contrast and ultraviolet illumination, X-ray topography and high-resolution X-ray diffraction, and secondary ion mass spectrometry. The obtained results allowed for creating a growth model of an ammonothermal GaN crystal on a lenticular seed. These findings are of great importance for the general understanding of the basic ammonothermal crystal growth process of GaN

On Stress-Induced Polarization Effect in Ammonothermally Grown GaN Crystals

The results of basic ammonothermal crystallization of gallium nitride are described. The material is mainly analyzed in terms of the formation of stress (called stress-induced polarization effect) and defects (threading dislocations) appearing due to a stress relaxation process. Gallium nitride grown in different positions of the crystallization zone is examined in cross-polarized light. Interfaces between native ammonothermal seeds and new-grown gallium nitride layers are investigated in ultraviolet light. The etch pit densities in the seeds and the layers is determined and compared. Based on the obtained results a model of stress and defect formation is presented. New solutions for improving the structural quality of basic ammonothermal gallium nitride crystals are proposed