On purposeful systems : Russelle L. Ackoff and Fred E. Emery. 288 pages,diagrams, 6x9in., Aldine-Atherton; Chicago,I11., Tavistock,London, 1972. Price, $12.95 (£3.50).

A closed-form analytical expression for evaluation of the output noise voltage of active-R filters has been developed. The expression is applicable to any low-pass, band-pass or high-pass two amplifier second order active-R realization. The expression for the noise voltage has been derived in terms of the filter specifications and parameters of noise sources contained within the filter. Thus, it is very convenient for practical calculations. The expression is also useful for obtaining a design that minimizes the magnitude of the output noise. Experimental measurements indicate close agreement with the theroetical analysis.     

Frameworks for integrating interdisciplinary research

Interdisciplinary research can be defined by the presence of substantive, internalized linkages among component analyses. Three levels of integration of component analyses are defined. The weakest is associated with multidisciplinary research in which components stand on their own. Integration here involves editorial organization, consistent terminology, and concordant concepts. The strongest level involves a shared, over-arching theoretical framework which welds components into a unit. Most interdisciplinary research can realistically aspire only to an intermediate level of integration wherein disciplinary components serve as substantive inputs to each other.Attainment of well-integrated interdisciplinary research is a complex task. This study identifies four frameworks useful in integration based on a probe of 24 technology assessments. Common group learning generates a common intellectual property belonging to the research group. It yields well-integrated research, but often at the cost of a loss of depth of analysis. Formal modeling can structure interrelationships, and, thereby, serve as an integrating framework. Modeling is most applicable to well-specified problems, but it can contribute, in conjunction with other frameworks, to broader, policy-oriented studies as well. Negotiation among experts takes place at the common boundaries between component analyses as these substantively affect each other's findings. It preserves the full depth of expertise and can be used in broad-ranging studies. Integration by the project leader establishes one person as the sole repository of composite knowledge, obtained through one-to-one interactions with assorted experts. It is not well-suited to interdisciplinary research, except in small-scale studies.     

Survival is not Mandatory

震惊、气愤、厌烦,甚至可能还有恼怒,这些都是一个好的主旨演讲应该在听众中引发的情绪反应.我的讲话将会刻意煽情.如果在随后的几分钟时间里,我能设法激起在座大部分人的义愤,那对于我来说将是巨大的成功.     

Relative Contributions of Prekindergarten and Kindergarten to Children's Literacy and Mathematics Skills

Research Findings: A difficulty for developmental researchers is disambiguating children's general maturation from the influence of schooling. In this study, we use a natural experiment to examine the influence of prekindergarten and kindergarten schooling experiences on the development of literacy and mathematics. Children (n = 60) whose birthdates fell within 2 months of the state-determined cutoff date for prekindergarten and kindergarten entry were administered 4 subtests of the Woodcock–Johnson III Tests of Achievement in the fall and spring of the school year. Using hierarchical linear modeling coupled with propensity score matching, we found that children who were starting kindergarten and who had prior experience in prekindergarten had higher scores on measures of phonological awareness, early reading, and mathematics skills than did children who had not attended prekindergarten previously, even though they were essentially the same age. Fall vocabulary scores did not differ in relation to whether children had prekindergarten experience. In addition, although children who attended kindergarten as well as those who attended prekindergarten exhibited growth on all measures during the school year, children who attended kindergarten demonstrated greater gains in early reading and vocabulary during the school year. Practice or Policy: These findings highlight the potential of early schooling processes to facilitate children's intellectual growth.