Bilinear,dynamic single-ports and bond graphs of economic systems

It is shown that reinvestment and inventory effects can be described in 0431 0368 bond-graph terms. The associated differential equations in price and order-flow 0431 0368 V variables are bilinear forms. These effects are the fundamental inertia and compliance 0431 0368 V 3 of economic bond graph theory. Properties of the components and example market 0431 0368 V 3 graphs are discussed.     

Replacing points by compacta in neural network approximation

It is shown that cartesian product and pointwise-sum with a fixed compact set preserve various approximation-theoretic properties. Results for pointwise-sum are proved for F-spaces and so hold for any normed linear space, while the other results hold in general metric spaces. Applications are given to approximation of L_p-functions on the d-dimensional cube, 1?p<∞, by linear combinations of half-space characteristic functions; i.e., by Heaviside perceptron networks.     

Copyright or copyleft?: An analysis of property regimes for software development

Two property regimes for software development may be distinguished. Within corporations, on the one hand, a Private Regime obtains which excludes all outsiders from access to a firm's software assets. It is shown how the protective instruments of secrecy and both copyright and patent have been strengthened considerably during the last two decades. On the other, a Public Regime among hackers may be distinguished, initiated by individuals, organizations or firms, in which source code is freely exchanged. It is argued that copyright is put to novel use here: claiming their rights, authors write ‘open source licenses’ that allow public usage of the code, while at the same time regulating the inclusion of users. A ‘regulated commons’ is created. The analysis focuses successively on the most important open source licenses to emerge, the problem of possible incompatibility between them (especially as far as the dominant General Public License is concerned), and the fragmentation into several user communities that may result.     

Adolescents’ Friendships,Academic Achievement,and Risk Behaviors: Same-Behavior and Cross-Behavior Selection and Influence Processes

This study examined to what extent adolescents’ and their friends’ risk behaviors (i.e., delinquency and alcohol use) hinder or promote their academic achievement (grade point average [GPA]), and vice versa. Longitudinal data were used (N = 1,219 seventh- to ninth-grade adolescents; M_age = 13.69). Results showed that risk behaviors negatively affected adolescents’ GPA, whereas GPA protected against engaging in risk behaviors. Moreover, adolescents tended to select friends who have similar behaviors and friends’ behaviors became more similar over time (same-behavior selection and influence). Furthermore, although same-behavior effects seemed to dominate, evidence was found for some cross-behavior selection effects and a tendency in seventh grade for cross-behavior influence effects. Concluding, it is important to investigate the interplay between different behaviors with longitudinal social network analysis.     

Elementary teachers’ science subject matter knowledge across the teacher career cycle

Although widely touted as important, there is little evidence regarding the influence of teaching experience on elementary teachers' science subject matter knowledge (SMK). To better understand this phenomenon, we administered an assessment of science topics taught in the fifth and sixth grades to 169 preservice teachers, 231 fifth-grade teachers, and 208 sixth-grade teachers. We then compared the mean scores of teachers at different stages in the career cycle using one-way and two-way ANOVA and explored the relationship between SMK scores and years of teaching experience using regression analysis. Findings indicate that (i) being assigned to a specific grade level had an impact on teachers' SMK for topics included in the grade level, (ii) teachers' SMK scores were lower later in their careers for both science topics they had never taught and for science topics they were responsible for teaching, and (iii) results differed for fifth and sixth grades. This study adds to the existing literature through the examination of a large sample of elementary teachers, with teachers of varying years of experience, while focusing on the science topics these teachers are responsible for teaching. The results of this study provide strong evidence that (i) years of experience teaching specific science topics is associated with the development of teachers' knowledge of these topics, and (ii) teaching experience, what teachers do in the context of their everyday practice, can be an effective means of self-directed learning for teachers. There is also evidence that this influence is not uniform across years of teaching experience or science topics taught. These findings raise important implications about future research into the mechanism of SMK development through teaching experience and teacher grade-level assignments.     

Towards a truer multicultural science education: how whiteness impacts science education

Cultural Studies of Science Education - The hope for multicultural, culturally competent, and diverse perspectives in science education falls short if theoretical considerations of whiteness are...     

Understanding the Use of Student-Centered Teaching Methods in Undergraduate Chemistry Courses

A growing body of research suggests that student-centered teaching methods are associated with positive learning outcomes for undergraduate students. Yet, the extent of their use and factors leading to their adoption in fields, such as chemistry, continue to be under-explored. Utilizing survey data collected during 2015, we begin to fill this gap, first by considering the degree to which faculty and instructors use and plan to use various student-centered teaching methods in their undergraduate chemistry courses. Then, we examine three potential factors that may help us understand variation in (1) use of and (2) intentions to implement student-centered methods: attitudes toward teaching methods; teaching approaches; and institutional characteristics. Importantly, our findings suggest attitudes and individual teaching approaches are significant predictors of the use and intention to implement student-centered methods in the classroom. Perhaps surprisingly, several institutional factors examined (such as class size, percentage of time spent teaching, and type of institution) play no significant role. Given the positive student outcomes associated with various student-centered methods reported in literature, these findings suggest potential avenues for faculty and instructors’ professional development toward further implementation of these methods.

     

Enhancement and constraint: student-mothers’ experiences of higher vocational education,emotion and time

Student-mothers who study vocationally related higher education programmes are a relatively under-researched group. Specifically, there is a paucity of research into the emotions that these learners experience. This article discusses a qualitative investigation that examined the emotional narratives that a group of vocational student-mothers offered. They were studying for a foundation degree for teaching assistants at a university in the North of England. The student-mothers were largely found to have experienced positive emotions. However, familial and workplace guilt had also been encountered. These emotions emanated from notions about how family and workplace time should be used. Student-mothers managed this cognitive dissonance by stressing the reciprocal relationships that existed between their studies, family lives and school work. However, for many of these learners familial and workplace guilt was a strong and continuing emotion.     

If we build it,will they come? The effect of new athletic facilities on recruiting rankings for power five football and men's basketball programs

College athletics is currently in the midst of a building boom in which universities are competing with each other to reach an always-increasing standard of lavish athletic facilities. While these facilities are costing in the tens or hundreds of millions of dollars, little research is examining the return on investment for athletic programs. The purpose of this study was to examine the effect of new athletic facilities on recruiting rankings for Power Five football and men's basketball programs. Data was collected on athletic facilities newly constructed or renovated from 2005 through 2015 at Power Five NCAA Division I programs. Using LSDV fixed effects regression models, results found a lack of significant improvement within football and basketball recruiting rankings following the completion of new athletic facilities, but some significance in the two years before the project was completed. Significant control variables also highlighted the effects that coaching changes can have on recruiting.