The Grand Challenges Discourse: Transforming Identity Work in Science and Science Policy

This article analyzes the concept of “grand challenges” as part of a shift in how scientists and policymakers frame and communicate their respective agendas. The history of the grand challenges discourse helps to understand how identity work in science and science policy has been transformed in recent decades. Furthermore, the question is raised whether this discourse is only an indicator, or also a factor in this transformation. Building on conceptual history and historical semantics, the two parts of the article reconstruct two discursive shifts. First, the observation that in scientific communication references to “problems” are increasingly substituted by references to “challenges” indicates a broader cultural trend of how attitudes towards what is problematic have shifted in the last decades. Second, as the grand challenges discourse is rooted in the sphere of sports and competition, it introduces a specific new set of societal values and practices into the spheres of science and technology. The article concludes that this process can be characterized as the sportification of science, which contributes to self-mobilization and, ultimately, to self-optimization of the participating scientists, engineers, and policymakers.     

Application of the Bayes＇ theory to the failure rate evaluation of electrical apparatus

The Weibull distribution has been widely used in reliability fields. A mixed Weibull distribution represents a population that consists of several Weibull subpopulations. In this paper, a new approach which combines the least-squares method with Bayes＇ theorem, takes advantage of the parameter estimation for single Weibull distribution is developed to estimate the parameters of each subpopulation. The estimates given by this paper also satisfy the maximum likelihood equation. The estimates of the failure rate of the mixed Weibull population are given. An actual test data is computed by using the proposed method. The Kolmogorov-Smirnov goodness-of-fit test turns out that the proposed method yields more accurate result.     

Reciprocal Negative Affect in Parent-Child Interactions and Children's Peer Competency

The relationship between preschool children's peer competency and the exchange of reciprocal negative affect displays during physical play with parents was examined. Teacher ratings of children's peer competency were obtained from children's preschools. Parents and children (41 families) were observed during a physical play paradigm called "the hand game" which permitted physically stimulating play, yet which also permitted clear recording of participants' facial expressions. Interactions were coded second by second for 8 min using a system of 12 mutually exclusive and exhaustive codes to categorize the affect displayed by participants. Fathers who typically responded to their children's negative affect displays with negative affect of their own had children who shared less, were more aggressive, and avoided others. Implications of the findings for theories of family-peer relationships are discussed.     

A new patch antenna with metamaterial cover

INTRODUCTION Investigation of metamaterials is currently one of the most active frontiers in engineering and physics. Metamaterials are also called backward-wave mate- rials, double-negative materials, or left-handed mate- rials. Left-handed materials were proposed by Vese- lago (1968). The applications of metamaterials are widely spread in many fields (Pendry, 2000; Grbic and Eleftheriades, 2003; Foteinopoulou et al., 2003), such as imaging apparatus, planar light wave circuits, optica…     

Taiwanese Grandmothers: Strengths and Learning Needs as Perceived by Grandmothers,Mothers, and Granddaughters

The purposes of this study were to (a) determine how three generations of females from the same families perceived the grandmothers, (b) identify strengths and learning needs of the grandmothers, and (c) recommend guidelines and curriculum themes to assist the grandmothers in adjusting to change. The 348 Taiwanese subjects included grandmothers (n = 116), mothers (n = 116), and teenage granddaughters (n = 116). Subjects completed a Mandarin version of the Grandparent Strengths and Needs Inventory. Each generation reported favorable ratings for grandmothers on the frustration, difficulty, information needs, and satisfaction scales. Unfavorable ratings were given for the teaching and success scales.     

The effect of teacher education programs on future elementary mathematics teachers’ knowledge: a five-country analysis using TEDS-M data

This article addresses the problem of how opportunities to learn in teacher education programs influence future elementary mathematics teachers’ knowledge. This study used data collected for the Teacher Education and Development Study in Mathematics (TEDS-M). TEDS-M measured the mathematics content knowledge (MCK) and the mathematics pedagogical content knowledge (MPCK) of future teachers in their final year in teacher preparation programs. The purpose of this study is to explore whether elementary teaching candidates’ MCK and MPCK are associated with their opportunities to learn in mathematics courses and mathematics methods courses in five countries. The results showed that opportunities to learn in some teacher preparation components are more important than in other components.