Ethnic diversity and trust in the school context: When do adolescents trust their peers and people in general?

SUMMARY OF THE DISSERTATION ETHNIC DIVERSITY AND TRUST IN THE SCHOOL CONTEXT: WHEN DO ADOLESCENTS TRUST THEIR PEERS AND PEOPLE IN GENERAL? BY ANDREA WINGEN Trust is an essential part of social life and important for successful human interaction. Especially social trust, that is trust in strangers, is crucial and has been linked to numerous positive consequences for individuals and society as a whole. This thesis focuses on trust in little-known and unknown peers and people in general, in particular during early adolescence – an age group which has received very little attention in research so far. Thereby, I focus on possible influencing factors specific to the school context. Schools as places where young people spend the majority of their time in close proximity to many other peers likely shape adolescents’ understanding of the world they live in and their place within it and thereby influence their trust in other people. The first and second studies presented in this thesis (Chapters 2 and 3) suggest that the group composition within the school grade and class relates to adolescents’ social trust within and beyond the school context. The share of the ethnic majority (i.e., students without migration background) in the school grade positively relates to students' trust in unknown peers within the school grade and people in general (Chapter 2). The alignment of ethnic origin and gender in the school class (i.e., if many fellow students of the same ethnic origin also belong to the same gender, while many students of another ethnic origin belong to a different gender) is negatively associated with both types of social trust for ethnic majority students (Chapter 3). This thesis further analyses the relationship between individuals’ social standing within the school grade and trust in little-known (Chapter 4) as well as unknown peers and people in general. In contrast to the group composition within the school class or grade, the social standing within the school grade is associated differently with trust in people in general compared to trust in little-known or unknown peers within the school grade. Overall, this thesis illustrates the importance of the school context in shaping adolescents’ trust in peers and people in general

A Semi-Blind Source Separation Method for Differential Optical Absorption Spectroscopy of Atmospheric Gas Mixtures

Differential optical absorption spectroscopy (DOAS) is a powerful tool for detecting and quantifying trace gases in atmospheric chemistry \cite{Platt_Stutz08}. DOAS spectra consist of a linear combination of complex multi-peak multi-scale structures. Most DOAS analysis routines in use today are based on least squares techniques, for example, the approach developed in the 1970s uses polynomial fits to remove a slowly varying background, and known reference spectra to retrieve the identity and concentrations of reference gases. An open problem is to identify unknown gases in the fitting residuals for complex atmospheric mixtures. In this work, we develop a novel three step semi-blind source separation method. The first step uses a multi-resolution analysis to remove the slow-varying and fast-varying components in the DOAS spectral data matrix $X$. The second step decomposes the preprocessed data $\hat{X}$ in the first step into a linear combination of the reference spectra plus a remainder, or $\hat{X} = A\,S + R$, where columns of matrix $A$ are known reference spectra, and the matrix $S$ contains the unknown non-negative coefficients that are proportional to concentration. The second step is realized by a convex minimization problem $S = \mathrm{arg} \min \mathrm{norm}\,(\hat{X} - A\,S)$, where the norm is a hybrid $\ell_1/\ell_2$ norm (Huber estimator) that helps to maintain the non-negativity of $S$. The third step performs a blind independent component analysis of the remainder matrix $R$ to extract remnant gas components. We first illustrate the proposed method in processing a set of DOAS experimental data by a satisfactory blind extraction of an a-priori unknown trace gas (ozone) from the remainder matrix. Numerical results also show that the method can identify multiple trace gases from the residuals.Comment: submitted to Journal of Scientific Computin

Survey of the Attitudes of Parents Toward Vocational Agriculture in South Dakota

Many vocational agriculture teachers, professional men and lay citizens believe that in the process of educating the farm youth of South Dakota in secondary schools, the vocational agriculture teachers have been doing an excellent job. However there have been remarks made at times not entirely in accord with the program. The fact that some parents have adverse criticism regarding some phase of vocational agriculture instruction in our high school curriculum may or may not be indicative of the attitude taken by the majority of the parents of students in the program. This survey endeavors to accentuate the importance of parent-teacher relationships in the vocational agriculture program. The vocational agriculture teacher, valuing his program with high esteem, feels that the program cannot be replaced in the high school curriculum. But what is the attitude of the parents toward this program? Do they feel a need for it? Do they believe that vocational agriculture is a means to a better end? There are so many questions that, if answered, could be an invaluable aid to teacher-parent relationships

Experimental study of timers implemented in bipolar and cmos technologies

В данной статье исследуются микросхемы таймеров, выполненных по биполярной и КМОП технологиям. Приводятся расчеты, а также практическая реализация и результаты эксперимента. Делается вывод о том, какой из генераторов, в основе которых лежат таймеры, более долговечен и экономичен в отношении к потреблению электроэнергии.In this article, we study the timer ICs implemented in bipolar and CMOS technologies. Calculations of the circuit components are given, as well as practical implementation and experimental results. We determine which of the timers based generators is better with respect to energy consumption